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prefect
19-06-2009, 10:30 AM
On that pommy Grand Designs program it shows kipper houses with pipes buried under the ground where the soil temperature remains a stable 13 degrees.
My question is, say its 0 degrees in the house one morning will the maximum temp the house will be heated to be 13 degrees by turning on the heat pump?
Do you then need outside energy to get the temperature topped up to a livable temperature say 20 degrees?

Rob99
19-06-2009, 10:49 AM
The pipes in the ground are used for the heat transfer.

Instead of the machine having to work with 0 outside and trying to heat to 20 inside. It works more efficiently if it only has to convert 13 into 20.

prefect
19-06-2009, 11:17 AM
Can the temperature of the house be raised to more than 13 deg from the ground?

nofam
19-06-2009, 11:34 AM
Can the temperature of the house be raised to more than 13 deg from the ground?

Yes - as Rob says, it just the heat pump a better starting temperature to work with. Basically, the compressor pressurizes the refrigerant gas, which causes it to heat up (like when you pump up a a bike tyre, the hand pump gets hot), and it passed over a heat sink to collect the heat - this is then blown out into your room via a fan etc. Once the coolant has gone over the heat pump, it moves through a valve which depressurizes and cools it. The process then starts again.

When you want cooling, the system just works in reverse. The ground-based system is important, as the greater the difference between the temperature inside the heating pipes, and outside the heating pipes, the more power is needed to compress the refrigerant, and therefore the less efficient the units are.

gary67
19-06-2009, 06:36 PM
There is a website here (http://www.bluebell-bungalow.co.uk/) all about the house. It's very near to where I come from about 30 miles away. I don't think the ground heat will lift the house above 13 degrees it just means the heat pump only has to go from 13 to 20 and not from 0 to 20