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wmoore
29-06-2005, 06:50 PM
Hi

Does anyone have a Home ventilation system (eg DVS etc) installed in their
home. How Good is it and does it get rid of all condensation ?
Also why did you go with that company ?

Thanks

Warrick

FoxyMX
29-06-2005, 07:48 PM
Does anyone have a Home ventilation system (eg DVS etc) installed in their home. Yes. Have had a MoistureMaster unit for three years.


How Good is it and does it get rid of all condensation ?It is very good. It does not prevent 100% of the condensation all of the time but it would be better than 75% and what does occur disappears much quicker than without it.

If you have a condensation problem I would definitely recommend DVS.

zqwerty
29-06-2005, 08:02 PM
If you have a tile roof don't bother, the roof space needs to be enclosed. Very expensive for what it is, a speed controlled fan with filter, bringing warm air, except in winter, from the roof space and feeding it through the ceiling and into your house. You get all the pollution, smoke, smells etc when the wind is right. Kind of works, but not that good.

somebody
29-06-2005, 08:59 PM
I disagree zqwerty. The ventilation systems require a constant circulation of air from outside the house, and the kits generally come with 2 vents to put in the eaves of the house (well mine did anyway)

We have a Weiss HVS system (basically the same as the DVS), and it works brilliantly. We have a tile roof which is very well ventilated, and it provides dry air into the house 24/hrs a day. The only downside is that the air coming in is quite cool.

To counter this, we have installed an "Air Tempering Unit" which is basically an inline heater, and while it doesn't heat the house as such, the air coming in isn't cold - so recently when it's been 2degrees outside int he morning, inside it's about 13degrees or so, without heating on. In terms of running costs, you'll find that even though you spend money on the power bill with the unit, you save money in heating.

It's well worth it - my system only cost just over $1400 all up (I installed it myself), and it makes a huge difference. Windows still get a little bit of condenstation in rooms where people are sleeping in, but otherwise it works a treat. My reason was price - basically the same system, (this is a NZ made unit) for about half the price - a quote from Moisturemaster was around the $2800 mark. Installation is simple, except you should get an electrician to do the wiring part.

I got mine from Mitre10 Mega in Hastings.

EX-WESTY
29-06-2005, 09:05 PM
We have had one installed in our house for about 7 years now.
We went for the DVS and two outlets due to the size of the house.

I have a tile roof and have never found that a problem at all in regards to its operation.

The unit is set to run at full speed when the roof space is between 18 and 24 degrees c and slows to 10% when under 18c or completely shuts off over 25c so as not to overheat the house.

Powerbill wise you don't even notice it probably 10-20 cents a day, way less than running a dehumidifier for even a hour or two.

Effectiveness My wife used to grab a towel and bucket and squeegee most mornings and go from room to room and wipe down the windows and sills. The house was 2-3 years old at that time so it wasn't moisture coming out of the timber. The house construction is concrete floor, brick and tile, aluminium joinery.

Since we had the DVS installed the problem was cured after a few months and I haven't seen the sqeegee, bucket and towel used for that purpose since.
Even during the winter it will still kick into full speed at times and that will change the entire volume of air in the house in around 3 hours. why she still insists on wanting to leave windows and doors open for fresh air I can't figure or is just to make it easier for the mice to come in and find a nice, warm cosy place for the winter.......

In regards to the comment above of installing a air tempering unit and heating the incoming air, I wouldn't bother.
Hot air rises and that in no way with the flow coming thru it ever heat the incoming air sufficiently or noticeably raise the temperature of the house. All it will most probably do it raise the power bills heaps. My house has insulation (batts or similar in the walls) and rock wall in the ceiling.

I live in south auckland and we use no other heating in the house usually, and no I'm not rugged up ike a mummy either.

If you wish to heat the house, a heat pump is the way to go and i have looked at them as well, but I think 3k buys a sh*t load of power for the 2kw fan heater we run a few times a year.....

Prescott
29-06-2005, 09:07 PM
if your having a condensation problem, why not leave a window slighty open?

somebody
29-06-2005, 09:38 PM
I do have to say, the air tempering unit did make a hell of a difference. When we first installed the system about 3 months ago, we didn't have the air tempering unit connected to the power. Even though it was only autumn, you would wake up in the morning and the air would be so cold that you could see your breath. Now, even on 2-degree mornings, the air in the house isn't too bad - at least it isn't cold.

This might just be because of my tile roof - it's about 40 years old, and is very well ventilated - eg. you can stand in the roof space and feel the wind. During summer, the roof space is still relatively cool, and in winter, it's absolutely freezing in the mornings.

FoxyMX
30-06-2005, 09:52 AM
If you have a tile roof don't bother, the roof space needs to be enclosed. Don't talk utter rubbish. The roof on this house is an unlined concrete tile job and the DVS system works very well. It could possibly work better if the roof was steel but to say it is a waste of time because it is a tile roof is just untrue.


Very expensive for what it is, a speed controlled fan with filter, bringing warm air, except in winter, from the roof space and feeding it through the ceiling and into your house. Expensive is a relative term. Sure it isn't "cheap" for what it is but it is a lot cheaper than replacing mouldy carpet, curtains and clothing every few years in a damp house, not to mention the nuisance and expense of cleaning mould off ceilings and walls and having to repaint them. Don't forget your health either - a family member's asthma cleared up after the DVS was installed.

Remember, too, that it may be more expensive to purchase than a dehumidifier but is much cheaper to run than the latter. It also deals with the whole house, not just a couple of rooms near where a dehumidifier would be placed. No one has to remember to empty buckets of water every few hours, either.


You get all the pollution, smoke, smells etc when the wind is right. Kind of works, but not that good.This area can get pretty bad with smoke pollution on still nights and there have been nights when the smoke from the neighbour across the road's very stinky chimney has been smelt but it is not very often. I believe that the latest systems have better filters in them that address this issue if you live in an area of high pollution but ordinary "smells" are not normally detected. I have an extremely acute sense of smell so I would be the first one complaining if it was bad.

Out of interest, do you have a DVS yourself, zqwerty?

pctek
30-06-2005, 12:51 PM
The best ventilated houses are old villas.

zqwerty
30-06-2005, 04:41 PM
Yes we do have a DVS. The idea is that the roof space will act as a reservoir of warmth from the heat rising from the house below. This air will not be saturated with moisture because it is essentially air from the outside heated by the upward losses from the house. However the tile roof leaks like a sieve and the end result is a lot of cold, sometimes freezing air being introduced to the house at the ceiling level. When it is raining the air is saturated with moisture.

There is an improvement as far as condensation goes with regards to the windows but some of that is due to the house just being colder.

I use a Scoopy in my part of the house to clean the windows in the morning but I am in a small flat adjoining the main DVS serviced house with "only" 8 large windows to clean every day.

Do you know what a Scoopy is?

http://www.cleanware.co.nz/product_info.php?products_id=140

They work well, we have 3 of them for the days that the DVS is not quite up to the task.

FoxyMX
30-06-2005, 05:21 PM
Yes we do have a DVS. The idea is that the roof space will act as a reservoir of warmth from the heat rising from the house below. This air will not be saturated with moisture because it is essentially air from the outside heated by the upward losses from the house. The air in the roof space is not heated mainly by warmth rising from the house below, it is the sun shining on the roof that provides most of the warm air in the roof space.


However the tile roof leaks like a sieve and the end result is a lot of cold, sometimes freezing air being introduced to the house at the ceiling level. When it is raining the air is saturated with moisture.Correct, but due to all the moisture released during the day from cooking, showers, baths, laundry, etc, not to mention just plain breathing, the air inside nearly always contains more moisture than the outside. See this page (http://www.condensation.co.nz/scripts/faq.html#11) for more information.


There is an improvement as far as condensation goes with regards to the windows but some of that is due to the house just being colder.If your DVS is not making a big difference to the condensation levels in your house then there could be some factor of the installation that is preventing the system doing its job, eg a bathroom fan outlet or open window close to the DVS outlet that results in the air going straight outside instead of circulating around the house. Or maybe the unit you have is insufficient for the size of the dwelling it services.

zqwerty
30-06-2005, 05:43 PM
Nope the house has just been reinsulated to the latest standards, Batts in the roof, underfloor insulation, all external windows and doors are kept shut all the time, internal doors left slightly ajar as per DVS instructions. There are no outlets/inlets other than DVS, electricity bill for last month for one 85 year old lady living alone, wait for it: $260. She basically lives in one room all day and only retires to bedroom at night. Temperature in passageway 20 feet away from DVS outlet has never been higher than 17degC all winter. If DVS is switched off goes up to 20degC immediately. The DVS is fed in over nightstore heater to heat the incoming air as much as possible.

Heaven knows how old people are surviving the winter if they are less well off than Mum now that we are being ripped off by privatized electricity system.

somebody
30-06-2005, 06:26 PM
I have mine set at about twice the recommended fan speed (ie. twice the "House size" setting) in order to get it to work properly. It works fine at this setting, even with a very very well ventilated roof.

EX-WESTY
30-06-2005, 10:22 PM
, electricity bill for last month for one 85 year old lady living alone, wait for it: $260. She basically lives in one room all day and only retires to bedroom at night. Temperature in passageway 20 feet away from DVS outlet has never been higher than 17degC all winter. If DVS is switched off goes up to 20degC immediately. The DVS is fed in over nightstore heater to heat the incoming air as much as possible.

Heaven knows how old people are surviving the winter if they are less well off than Mum now that we are being ripped off by privatized electricity system.

What the hell is she running in that house?

I have a family of 4 in my house, PC running 24/7 usually, TV, dishwasher used once daily, front loader washing machine, fridge and chest freezer, DVS and spa pool and an average power bill of around $140 a month
Next month will be higher as her indoors has been giving the drier a work out to keep up with the washing.

Seriously one would have to wonder if the nite store heater is wired correctly and is on the right tarrif.
Either that or she's running fan heaters in the room all day or the neighbours have tapped into her line for their "grow' operation next door.
At that price i'd kill the night store heater and put in a heat pump if she feels the cold that much.

zqwerty
01-07-2005, 12:55 AM
Nothing special that I know of and I have looked into this. Remember she is in the house nearly all the time. 1KW bar heater (she doesn't like the sound that fan heaters make) is on most of the day in the small winter living room. 700W heater in the toilet some of the time. Dishwasher used approx every 3 days. Washing machine approx every 3 days. Of course fridge/freezer always connected. TV at night. NightStore on the usual routine recommended, with the powersavings, and they are happening, I have checked the bill. Half price for that. Hot water cylinder uses quite a bit.
I live next door, in an adjoining flat, I have my hot water tank on for 5 hours every 3 days, computer on 6/7 hours/day, 500W heater on for same time as computer, I am away during the day so not same heating usage as Mum, have power saving bulbs for most lighting, once upon a time in the middle 80's my bill was $27 for 3 months with hot water always on now it is $56/month in winter, $43 in summer, line charges are a large part of my bill. Nothing has changed in my installation since the 80's, the meter was changed about 10 years ago with only a small jump in bill. I have all my old bills here since those days, I could look at them again and do a better analysis but I am sure that even though I have economised the only thing that has really changed is that the price/KWh has increased exorbitantly.

zqwerty
01-07-2005, 01:05 AM
As a quick estimate, say she is using 2KW/hour for 20 hours a day for 30 days, that comes to $180 at 15c/KWh. It adds up quickly. Include line charges and a few extras like cooking a meal on the stove 3 times a week for an hour and there you have it.

EX-WESTY
01-07-2005, 07:12 PM
The way to kill the hot water bill is to put that on night rate if that's an option.

We have a 180L cylinder with a tempering valve so that the delivery temperature is 55c, I have bumped up the storage temperature to about 75-80c, which is fine for our draw of showers and dishwasher each day + the odd warm wash in the washing machine.
The heating for this option kicks in at 11pm and off again at 7am I recall and for this we average 200 units per month which equates to around $20 + the obligitory line charges.
A few years ago this was about $6 per month for hot water and our neighbours laughed till they checked our bill, then they asked how we did it and who to call.........

For those that draw heaps of hot water, heatpumps are now available as an option for that as well, endless supply and no ripple controls.

rufus
01-07-2006, 03:09 PM
We've just had a "Dry Air" system installed, it certainly dries the house and windows well, and we do recover some heat from above our gas heater which heats the roof air and is recirculated. But we are beginning to be concerned about the filtering, as we've all had continuous sinus infections for the last month (could be coincidence, time will tell I guess). We weren't told anything specific about the filter, it just looks like a sock on the inlet line. Is this enough to filter out bits of batts, for instance? Do some houses have asbestos in the roof? Any other hazards? We don't have any neighbours using fireplaces much, aren't concerned about outside air so much as inner roof air.

Graham L
01-07-2006, 03:27 PM
Zqwerty: if you have the house "properly insulated", you are using the ventilation system to drag cold winter air from the ceiling space and freezing the 85 year old. Turn it off.

There would be some point if there was no ceiling insulation, and you were recovering heat which has gone straight through the ceiling..

You're making it worse, by using this cold air to efficiently cool the night storage heater. No wonder she is running a bar heater all day.

pctek
01-07-2006, 03:53 PM
Geez, all this brilliant new technology. Glad I don't have any.
You know one thing I have noticed about condensation. People who use gas heating get masses of it.

We have a portable gas heater and if we use it, the room its in gets heaps.
Don't use it and the house is dry.
Electric heaters, in whatever form, bathrooms, fan, oil column etc, are deadly to power bills.
I'll be sticking to my wood fire.


Ex-Westy -> remember that in the South Island power costs more than in Auckland. This is a depressing fact regardless of which of the three power companies used down here.
Our power bill (with no electric heating) in Auckland was $100 - $120.
Here its been $130 (summer rate) and $186 (winter rate). Thats another new con I've found, this winter rate crap.

John W
01-07-2006, 03:57 PM
Interestig topic.

We have a 10yr old house, with recessed downlights everywhere. No point in putting in a DVS as more heat excapes up the DLights than a DVS could ever pump into a house.

Consumer last month? tested DVS systems, claimed most worked to some degree, but the claim of getting warm air from a roof space in Winter was bassically a lot of "hot air", sorry - had to get that in.

From my perspective, our last two houses had condensation probs until we installed a Dehumidifier, problems dried up within a week. Dehumidifier supplied warming air in its vicinity, created a pleasnt motor hum and tinkle when water fell into the collector.

So, for removing crying windows, Id recommend a dehumidifier, cheap to buy, run and you can store them away in the warmer, windier months. I tested three brands, Delonghi, Mitsubishi (both around $800) but went for $300 warehouse model, just as good performance wise, quieter then the other two and slimmer as well.

somebody
01-07-2006, 03:59 PM
umm... everything prior to Rufus' post is one year old or more.

Rufus: depending on the filter you have, it may or may not filter out particles from the pink batts. Some brands of ventilation systems sell charcoal or "hypo-allergenic" filters as an extra, designed to get rid of these smaller particles. Personally I haven't had any issues with bits of batts etc.

pctek
01-07-2006, 04:20 PM
our last two houses had condensation probs until we installed a Dehumidifier, problems dried up within a week.
But I'd rather fix the cause, not the effects.

godfather
01-07-2006, 05:31 PM
Geez, all this brilliant new technology. Glad I don't have any.
You know one thing I have noticed about condensation. People who use gas heating get masses of it.

We have a portable gas heater and if we use it, the room its in gets heaps.
Don't use it and the house is dry.


For every 1 kg of gas burnt in a portable (unflued) gas heater, or gas cooking hob, ~ 1.6 litres of water is released into the room.

Hence the condensation.

Cicero
01-07-2006, 08:29 PM
You know one thing I have noticed about condensation. People who use gas heating get masses of it.
So there you are PC,now you know to the last drop,how much you are getting.

pctek
01-07-2006, 08:53 PM
You know one thing I have noticed about condensation. People who use gas heating get masses of it.
So there you are PC,now you know to the last drop,how much you are getting.
No. Like I said, we have a wood burner now.

Cicero
01-07-2006, 11:16 PM
No. Like I said, we have a wood burner now.
This was a question of if,we saw you had a wood burner.

efhltd
30-05-2007, 01:23 AM
[spam removed]

winmacguy
30-05-2007, 06:26 AM
Hi

Does anyone have a Home ventilation system (eg DVS etc) installed in their
home. How Good is it and does it get rid of all condensation ?
Also why did you go with that company ?

Thanks

Warrick

We have the HRV system and yes it is very effective. We also have underfloor insulation which makes a big difference as well.

Black Ice
02-10-2007, 01:04 PM
We had an HRV system put in last week. This was 7.30am and the whole family was home. About 15-30mins after the installers left I noticed that my mobile phone and charger were gone from my bedroom! I had a business trip planned and so had to leave it to my father-in-law to contact HRV. A week later, I'm back and all they have done are suspended 2 people they thought were dodgy, (one of them called in sick after the job at our house) and offered to replace the mobile phone. No real remorse in fact the installation manager who was supposed to manage our 'compensation' was downright defensive, sarcastic and hung up on me! I tried to discuss the breach of security and how could they help turn this nasty experience round but I'm afraid I can't say I was happy with the way it was handled. BE CAREFUL not just of this firm as I don't know if they will fire anyone and so the guilty party might still be doing the rounds in Hamilton, but of all tradespeople, NZ doesn't seem as safe as it once was.

SurferJoe46
02-10-2007, 02:23 PM
I'm not following this logic at all.

Homes need to have 20-30% humidity to keep them livable....

We have to add moisture to the air to keep our noses from drying out and our skin cracking....we do that by triple-pane windows, R-values in the walls over 20, the ceiling over 35 and the floor over 15.

We have gas heat, but somehow the flue gasses never get into the home to allow condensation to collect on the windows.

We are not air-conditioned..I find that particularly drying to the air too. I like a swamp cooler better for overall cost and cooling. Homes that ARE AC'd have moisture injection devices to keep them humid.

Our windows remain basically closed all day in the cold months, open to allow the swamped air to escape in the daytime...and sometimes in the night too in the hotter months. I never installed the fireplace, and that might make a difference...possibly.

Our ceiling is solid injected foam all the way up to the ridgepole and all the trusses are inter-injected with the same product. At the peak, it is over 4 feet thick.

We have a snow load rating of 200 lbs/square foot, although we never see that kinda snow here in SoCal.

We can change the air in the whole house in less than 1 minute with the swamper not using the wetting pump.

We don't ever see condensate at all..not even on the windows or walls.

I think it's basically an insulation problem that your guys are having...stone, cement shingles or wood siding doesn't make a difference if the surface temperature on the inside cannot mingle with the outside temperature. Hope that makes sense.

Gas cooking DOES import some moisture, but we, like I said, bring moisture into the home for livability values.

If I see my breath in the house at any time...I then turn on the automatic heater controls which I shouldda done the night before!

zqwerty
02-10-2007, 03:32 PM
Wow blast from the past. I now have a de-humidifier and as well as remove the condensation from my kitchen/computer room, it also gives a bit of heating since, as is not pointed out anywhere in the literature, all the losses from a de-humidifier come out in the room it is running in, so even though cool air may emerge from the outlet the net effect is heating. I don't have to use my heater much when it is running. This Winter we have just had a spell of below 10deg C for more than three weeks in a row, the longest I can ever remember, and it was not too bad with the new de-humidifier and a bit of heating, yay.

wmoore
03-10-2007, 09:47 AM
update

We ended up getting a system from healthaire. Very good service and product. No pushy salespeople. And didn't talk crap.
Happy with thier product.

Brooko
03-10-2007, 09:28 PM
Interesting read - despite the age of the post. The amount of misinformation in some of the thread is astounding ........

When we moved to Invercargill 10 years ago, we brought a 50 year old family home - metal roof, not the greatest insulation (although we upgraded over time). Installed a multi-fuel burner. House was also well situated for sun. Had ongoing issues with condensation, mould, and (when we started the family) kids with asthma symptoms & intermittant flu every Winter. Living area warm because of the Logaire (burner) - but at nights the bedrooms etc would suffer temp drop to the low teens (we measured it). Ran the night-store but it didn't help a lot & definitely added to the power bill! Used a dehumidifer for drying - expensive (although we did not realise it).

Long story short ..... checked out 3 main Ventilation Systems Co's (HRV, DVS and Moisture Master). HRV were a nightmare - very expensive, recommended something we didn't want, and (very rudely) argued with me when I rang to advise them that we were going with another company (I advised as I always do - out of politeness for them giving their time in coming to see us). MM & DVS very similar systems, both costed well, and both work well. In-laws have a MM installed & they swear by it. We went with the DVS because they had a new gen control pad (G3) which allowed us better control of heat.

After DVS installed, house was both noticeably warmer and noticeably drier. Kids stopped getting flus, asthma a thing of the past. House also easier to heat. Power bill down - and this was in Winter. Could be below 10 deg outside in middle of day (but sunny) and we'd be getting 35 - 40 deg C trickling down from the roof (eg dry air from roof cavity, heated by sun on roof - free heat!). Can't say enough good things about the system - it really is that good!

Now to some of the misconceptions:
- heating from roof - see above. It works. With the G3 system, the fan regulates so that in Winter it turns itself up when the heat is there, and turns the fan down at night as the heat from the roof dissipates. Summer setting feeds cooler air at night faster for opposite effect. You will get better heat from metal roof as opposed to clay tile - but metal also cools more quickly.
- cost. DVS = approx 5c per day compared with 43c per 10 hours a dehudimifier runs (check it here (http://www.consumer.org.nz/topic.asp?category=Appliances&subcategory=Prices%20%26%20reliability&docid=2316&topic=Appliance%20running%20costs&title=Running%20costs&contenttype=summary&bhcp=1)).
- smell. Never noticed any smell from the DVS & remember almost everyone down here uses solid fuel burners. Simply not true.

We've just build a new house down here (been in it 2 weeks) and the first thing we organised during the build was to have a DVS installed. Everything is really well insulated & the house is really toasty with just the DVS (installed the heater unit as well but so far haven't used it) + a heatpump. House sits constantly around 20 deg. Cold here today - but the DVS was dragging down 35 C from the roof at mid-day. According to the G3 - roof temp has now dropped (11pm) to 13 deg, but house temp still at 18 deg. By morning it may drop another deg if it is really cold.

All in all, we've had nothing but a positive experience. Best investment we could have made IMHO.

zqwerty
03-10-2007, 10:22 PM
Yeah, try the DVS with a tile roof, you won't be so impressed.

Brooko
03-10-2007, 10:54 PM
Try it with a metal roof - you will be! :) (that includes metal tiles BTW).

Also zqwerty - I don't think you can blame your situation on the DVS poor performance. Have you actually approached DVS and explained issues to them and asked for help. We've been amazed at how good their feedback, expertise and suggestions are. They helped us with set-up. Am sure if you approached them - they would at least give some suggestions as to how you could improve your own situation.

zqwerty
03-10-2007, 11:03 PM
Well that's an impractical suggestion, how much would that cost!

Pity that the people who sold it to my parents didn't mention that drawback before they bought the DVS. Sucking stinky, cold, smoky air into the house which the filter, added after complaints, does something to alleviate, the smells and smoke I mean, not the cold.

Brooko
03-10-2007, 11:31 PM
Seems to me that it doesn't matter what I say does it - your mind is made up anyway.

Our experience with DVS has been all positive. My question still stands - have you been back to them, told them the problems you've had, and asked them for assistance in rectifying the situation?

Here is the website address (http://www.dvs.co.nz/). They have contact details on their website.

Oh & BTW - I wasn't suggesting your parents get a new roof. You commented that it's rubbish with tiles. I'm advising it's excellent with metal.

OP (way back) was asking for experiences. You've definitely covered the negatives - but I think you'll find that a lot of people who've used them are very happy. We know of 4 people with DVS or MM installed & not one negative comment.

Understand and sympathise re your position - but if you don't approach them to do something about it - then things won't improve - will they? Ball is in your court.

zqwerty
04-10-2007, 12:05 AM
They did everything they could about six years ago when it was installed and we complained.

It is not a matter of minds made up, it is a matter of bitter experience, and of a product being installed in an inappropriate situation, with, I dare say, the profit motive uppermost.

robbyp
04-10-2007, 03:58 PM
Interesting read - despite the age of the post. The amount of misinformation in some of the thread is astounding ........

When we moved to Invercargill 10 years ago, we brought a 50 year old family home - metal roof, not the greatest insulation (although we upgraded over time). Installed a multi-fuel burner. House was also well situated for sun. Had ongoing issues with condensation, mould, and (when we started the family) kids with asthma symptoms & intermittant flu every Winter. Living area warm because of the Logaire (burner) - but at nights the bedrooms etc would suffer temp drop to the low teens (we measured it). Ran the night-store but it didn't help a lot & definitely added to the power bill! Used a dehumidifer for drying - expensive (although we did not realise it).

Long story short ..... checked out 3 main Ventilation Systems Co's (HRV, DVS and Moisture Master). HRV were a nightmare - very expensive, recommended something we didn't want, and (very rudely) argued with me when I rang to advise them that we were going with another company (I advised as I always do - out of politeness for them giving their time in coming to see us). MM & DVS very similar systems, both costed well, and both work well. In-laws have a MM installed & they swear by it. We went with the DVS because they had a new gen control pad (G3) which allowed us better control of heat.

After DVS installed, house was both noticeably warmer and noticeably drier. Kids stopped getting flus, asthma a thing of the past. House also easier to heat. Power bill down - and this was in Winter. Could be below 10 deg outside in middle of day (but sunny) and we'd be getting 35 - 40 deg C trickling down from the roof (eg dry air from roof cavity, heated by sun on roof - free heat!). Can't say enough good things about the system - it really is that good!

Now to some of the misconceptions:
- heating from roof - see above. It works. With the G3 system, the fan regulates so that in Winter it turns itself up when the heat is there, and turns the fan down at night as the heat from the roof dissipates. Summer setting feeds cooler air at night faster for opposite effect. You will get better heat from metal roof as opposed to clay tile - but metal also cools more quickly.
- cost. DVS = approx 5c per day compared with 43c per 10 hours a dehudimifier runs (check it here (http://www.consumer.org.nz/topic.asp?category=Appliances&subcategory=Prices%20%26%20reliability&docid=2316&topic=Appliance%20running%20costs&title=Running%20costs&contenttype=summary&bhcp=1)).
- smell. Never noticed any smell from the DVS & remember almost everyone down here uses solid fuel burners. Simply not true.

We've just build a new house down here (been in it 2 weeks) and the first thing we organised during the build was to have a DVS installed. Everything is really well insulated & the house is really toasty with just the DVS (installed the heater unit as well but so far haven't used it) + a heatpump. House sits constantly around 20 deg. Cold here today - but the DVS was dragging down 35 C from the roof at mid-day. According to the G3 - roof temp has now dropped (11pm) to 13 deg, but house temp still at 18 deg. By morning it may drop another deg if it is really cold.

All in all, we've had nothing but a positive experience. Best investment we could have made IMHO.

They work ok in some houses, but not others, as not all houses are the same.

One problem with them is that they take the air from the roof, which often contains fibre glass insulation. This means that it is pumping fibre glass particles into the house. The filters they use aren't enough to prevent the microscopic fibre glass particles. Breathing in fibre glass particles is very dangerous for your future health.

SurferJoe46
04-10-2007, 04:19 PM
Yeah...it brings on future death.....

but then again, SOMETHING'S gotta kill ya.

Brooko
04-10-2007, 05:18 PM
They work ok in some houses, but not others, as not all houses are the same.

One problem with them is that they take the air from the roof, which often contains fibre glass insulation. This means that it is pumping fibre glass particles into the house. The filters they use aren't enough to prevent the microscopic fibre glass particles. Breathing in fibre glass particles is very dangerous for your future health.

Robby - agree on the fact that the systems appear to work better in some houses than others. We did the research before we decided to install.

Re your comment about the glass particles - and I'm referring here to Pink Batts. Our research says we are perfectly safe .......

The materials they use now are supposed to be safe (refer this pdf (http://www.insulationsolutions.com.au/pdf/MSDS-2004.pdf)).
Micron size for airborne f/glass particles is typically 5-6 micron. The standard G4 'sock' DVS filter will effectively filter 50 - 90% of these out.
If you were really concerned - you can upgrade the filter to an F5 which effectively filters 90% + of this micron size.

I'm pretty confident (after doing the initial research) that both my own health (and more importantly that of my family) is not at risk - and in fact the benefits (less moisture, mould, spores, pollen etc) are a big plus for my family's health.
Not only that, the DVS system is endorsed by the Auckland Asthma Society. Hardly think they would do this if the risks you stated are true.

robbyp
05-10-2007, 02:39 PM
Robby - agree on the fact that the systems appear to work better in some houses than others. We did the research before we decided to install.

Re your comment about the glass particles - and I'm referring here to Pink Batts. Our research says we are perfectly safe .......

The materials they use now are supposed to be safe (refer this pdf (http://www.insulationsolutions.com.au/pdf/MSDS-2004.pdf)).
Micron size for airborne f/glass particles is typically 5-6 micron. The standard G4 'sock' DVS filter will effectively filter 50 - 90% of these out.
If you were really concerned - you can upgrade the filter to an F5 which effectively filters 90% + of this micron size.

I'm pretty confident (after doing the initial research) that both my own health (and more importantly that of my family) is not at risk - and in fact the benefits (less moisture, mould, spores, pollen etc) are a big plus for my family's health.
Not only that, the DVS system is endorsed by the Auckland Asthma Society. Hardly think they would do this if the risks you stated are true.


Robby - agree on the fact that the systems appear to work better in some houses than others. We did the research before we decided to install.

Re your comment about the glass particles - and I'm referring here to Pink Batts. Our research says we are perfectly safe .......

The materials they use now are supposed to be safe (refer this pdf (http://www.insulationsolutions.com.au/pdf/MSDS-2004.pdf)).
Micron size for airborne f/glass particles is typically 5-6 micron. The standard G4 'sock' DVS filter will effectively filter 50 - 90% of these out.
If you were really concerned - you can upgrade the filter to an F5 which effectively filters 90% + of this micron size.

I'm pretty confident (after doing the initial research) that both my own health (and more importantly that of my family) is not at risk - and in fact the benefits (less moisture, mould, spores, pollen etc) are a big plus for my family's health.
Not only that, the DVS system is endorsed by the Auckland Asthma Society. Hardly think they would do this if the risks you stated are true.

I was informed the following by a well known wellington company that specialises in evironmentally friendly building solutions,about the problems with such ventillation systems.

My parents had one of these systems installed, against my advice, and they have found that it doesn't really work and wasn't a worthwhile investment. Their house is large, and is not a conventional design.

The potential harm caused by breathing in fibreglass insulation is still an unknown, but in the next 20 years, its effects potentially could be similar to that of asbestos. The fact is that the product isn't old enough to know, and in those situations it is wise to be cautious. Certainly it causes short term problems if you install the stuff without protection. Remember they were saying smoking was safe 60 years ago. There were builders installing the stuff without any form of protection, which may suffer in their old age. The standard filters on the ventillation systems don't prevent the microscopic particles getting through. . Even if they claim that that their finer filters stop 90% of fibre glass, that still means that 10% is still getting through.

Home ventillation systems may work ok in 40's to 70's style state type houses, which have a large attic space, which are essentially sealed boxes when the windows are closed. The roofing material makes a difference to their effectiveness, as attics can get very cold being outside the insulation envelope(although this depends on the design of the house), you could be pumping in cold air into your room, and then need more energy to heat the room. I think people are probably better off not having carpet in your house or at least the bedrooms, and opening the windows and regually vacuuming the house with a cleaner with hospital grade filtering. The problem is people kepp their windows closed, allowing spores to develop in the moist warm environment.

wmoore
05-10-2007, 09:11 PM
I was informed the following by a well known wellington company that specialises in evironmentally friendly building solutions,about the problems with such ventillation systems.

My parents had one of these systems installed, against my advice, and they have found that it doesn't really work and wasn't a worthwhile investment. Their house is large, and is not a conventional design.

The potential harm caused by breathing in fibreglass insulation is still an unknown, but in the next 20 years, its effects potentially could be similar to that of asbestos. The fact is that the product isn't old enough to know, and in those situations it is wise to be cautious. Certainly it causes short term problems if you install the stuff without protection. Remember they were saying smoking was safe 60 years ago. There were builders installing the stuff without any form of protection, which may suffer in their old age. The standard filters on the ventillation systems don't prevent the microscopic particles getting through. . Even if they claim that that their finer filters stop 90% of fibre glass, that still means that 10% is still getting through.

Home ventillation systems may work ok in 40's to 70's style state type houses, which have a large attic space, which are essentially sealed boxes when the windows are closed. The roofing material makes a difference to their effectiveness, as attics can get very cold being outside the insulation envelope(although this depends on the design of the house), you could be pumping in cold air into your room, and then need more energy to heat the room. I think people are probably better off not having carpet in your house or at least the bedrooms, and opening the windows and regually vacuuming the house with a cleaner with hospital grade filtering. The problem is people kepp their windows closed, allowing spores to develop in the moist warm environment.

For a real HRV system see www.dryair.co.nz The HRV that Marc Ellis advertise is not a proper HRV system. The Cleanaire system uses air from the outdoors to ventilate the home, while removing stale air from inside.
We installed a Healthaire which is a PPV system like HRV, DVS, MM.

Metla
05-10-2007, 09:17 PM
When I worked in Aussie we had to treat fibre glass exactly the same as we did asbestos, Breathing gear, suits, bagged and tagged, then sent to a specific landfill.

And yeah, Open a window.

Filtering your air is damn funny though.

Lmfao.

dvdasolutions
08-01-2008, 01:10 PM
I will not spam here ever again
I will not spam here ever again
I will not spam here ever again
I will not spam here ever again
I will not spam here ever again
I will not spam here ever again
I will not spam here ever again

Biggles
08-01-2008, 01:27 PM
Nice.

Cicero
08-01-2008, 01:35 PM
Nice.

It may pay to come back here,your pic suggests a certain tension arising of late!.New job to much to cope with?

Biggles
08-01-2008, 01:42 PM
It may pay to come back here,your pic suggests a certain tension arising of late!.New job to much to cope with?

Hardly, since the pic dates from my PCW days. I'm an angry man. Anyone will tell you.

Poppa John
08-01-2008, 01:56 PM
Hardly, since the pic dates from my PCW days. I'm an angry man. Anyone will tell you.

Your poor wife & children. Tried anger management?? PJ :D :D :D

Greg
08-01-2008, 01:57 PM
[edit] - posted in wrong thread! :blush:

Biggles
08-01-2008, 02:16 PM
Your poor wife & children. Tried anger management?? PJ :D :D :D

Well, COD4 has been helping. There's nothing like double-tapping a gun-toting Russian Ultra-nationalist in the head with your silenced pistol to help induce a sense of calm.

Cicero
08-01-2008, 03:30 PM
Hardly, since the pic dates from my PCW days. I'm an angry man. Anyone will tell you.

There must be some medicine apart from gaming that would help,poor Mrs,Buck.

We are talking primal scream here.

Roscoe
08-01-2008, 05:58 PM
Have to agree with you Surfer Joe. That is the reason we have a nose - to introduce humidity to the air we breath. Dry air is not the best for the human body. So why do you want to remove all the moisture in the air?

And like the thread on the dehumidifiers: what's wrong with opening the doors and windows?

It's simple, it's easy, it's non-polluting, uses no electricity.

I heartily recommend the open window and open door policy as some have already said.

Besides, as I understand it, the experts recommend keeping relative humidity (for humans) between 30% and 60%, with below 50% preferred to control dust mites.

SurferJoe46
09-01-2008, 03:23 AM
Currently there's a lot of foot dragging on lawsuits for mold/spores in homes and the legitimate effect on human and pets.

Typically...if a householder finds mold or fungi growing on a wet wall or one that was wet in some sort of water invasion, then the lawsuits fly..against the original contractor/designer or the manufacturer of whatever device it is that failed and caused the water damage.

The "diseases" proffered just aren't being caused by the lifeforms that grow in the walls or basements or whatever...according to some late emerging medical and scientific investigative results.

The observed threats are (seemingly) becoming more and more suspect to juries who are now becoming hesitant to award the great gobs of money to those who present as life-threatened and lifestyle-diminished individuals/families and pets.

Somehow the pseudo-science and personal injury attorneys saw a great big pile of free money and went for it. Since at the time there was NO real independent proof that these molds, etc might cause any effect on human or animal lungs that could not be naturally handled by the body, it was a vast arena that was rife with superstition and not with any true charts or history of actual deaths or infections: lawsuits and settlements were in the many-zeros-before-the-decimal category.

The current re-think of the original precedent-setting trial cases has set the insurance industry on a new Quixotic tilt..to debunk the theory that indeed these spores and fungi were actually dangerous or inconsistent with a safe environment in the first place.

Medically there is very little corroborating evidence that there is any cause-effect with these lifeforms either. Your great aunt Matilda or her ugly step-sister say just the opposite.

I know there are some who will knee-jerk this and dismiss the new scientific results..which are still trickling in...and say that they have personally had their lifespan(s) decreased, their gravidity diminished or sperm-counts are impinged or their house pets have a decreased symbiotic relationship with them.

Coughing, copious nasal discharges and pneumonia-like diseases etc are always suspect by social malcontents who would find a likely cause (for them) in modern lifestyles and supposed or suggested chemical intrusions into their lungs, eyes, bodies..etc. Maybe they should be looking at the black helicopters and checking them out for these aerobic problems.

Mercury has recently come to light as NOT the- or any- primary cause or mitigating agent of Alzheimer's disease. In newer and more strict environmentally regulated laws and results of those laws, mercury has not been evident in medically diagnosed cases of Alzheimer's, and yet the cases continue to multiply.

Even if mercury containment and much less environmental exposure had been cut by even a small percentage point..the original "scientific proof" (which had no real scientific proof at all) that mercury was indeed the primary cause of the condition, would now be showing serious inroads to control or incidences of the condition in real life experiences and observed happenings.

There's less mercury, yet Alzheimer's still incidentally climbs at astounding idiopathic percentages.

Back to the invading spores/fungi/mold cases which are just now seeing daylight and it now appears that fiberglass also isn't the bad guy most suspect or have heard of from the knee of their grandmothers and crazy aunts that every family keeps in the attic.

Asbestos is VERY MUCH A BAD GUY however..........


....so is drowning.

....so are gunshot wounds...and direct irradiation from Chernobyl-like situations.

Molds are slightly more suspect..as we all know that deeply inhaling the spores every day for the next 75 years might cause some respiratory distress....but the time cause-and-effect is yet to be accurately seen outside of a laboratory and truly not on humans.

It's not that humans are or are not affected by spores, etc..but no-one has volunteered to allow themselves to be a laboratory rat for their whole lifespan so that accurate results could be observed. They are looking for volunteers, however. Free meals, clothing and a GREAT medical plan all included.

Mice that were force-fed vast amounts of suspected spores have gained some weight and grown lethargic...but their lungs are still clear and normally functional at the time of dissection. Mice have not voiced opposition to laboratory lifestyles..at least they have not presented any viable demands.

Lungs on those animals forced to live in an artificially induced, heavily-laden atmosphere of fungi, molds and spores have shown some encapsulation of the invading lifeforms, but overall the effect is minimal at worst, non-existent at the least. Rats don't live all that long anyway.

My opinion..for what it's worth is to not let black mold run down my interior walls should I have any (mold, not the walls part) ...and not to deeply inhale or sniff any strange lifeforms. But that's just me.

pctek
09-01-2008, 07:26 AM
Currently there's a lot of foot dragging on lawsuits for mold/spores in homes and the legitimate effect on human and pets.


That would be cause there is a tendency to build your house fully sealed.
Put polystyrene under the floor.
Put the stuff in the walls, seal the windows and doors.

Then of course it sweats so you have to buy dehumidifiers or ventilation systems.

Its stupid.

Roscoe
09-01-2008, 08:13 AM
pctek: Are you certain it is stupid? Perhaps it is a conspiracy combined with a good sales pitch to make the uninitiated and gullible buy these systems to cope with a problem that should not really exist.

As has already been said, why not treat the cause? Open the doors and windows! It's not difficult - even a child could do it!

We have quarter-light windows that are open all the time, except in the coldest of Auckland weather. Security catches on them stop the burglars but not the fresh air. An easy, simple, no cost solution. Why not try it?

Biggles
09-01-2008, 08:19 AM
As has already been said, why not treat the cause? Open the doors and windows! It's not difficult - even a child could do it!

1] Open windows does not lower humidity. Excess Humidity causes discomfort.
2] Opening windows does not help asthma/hay fever sufferers who want to lower the amount of allergens in their atmosphere.
3] The HRV and similar systems are designed to also provide a base heating solution, while also providing filtered air for those suffering from allergies/asthma

BobM
09-01-2008, 12:14 PM
Ordinary LPG heater (non flued).
Every kg of LPG burnt, will put 1 kg of water into the room.
9 kg bottle = 9 kg water! That's a heck of a lot of condensation.
Flued heater, no condensation.
Problem solved.

pctek
09-01-2008, 12:24 PM
1] Open windows does not lower humidity. Excess Humidity causes discomfort.


Ah yes. Auckland. Who all need air conditioning.


But I wasn't talking about the climate. I meant sealed up modern houses.
Which is a different thing altogether.