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Last seen: Sep 14, 2026
@jamespa The DT will be what the DT will be, its determined by the equations you set out above. This means that most of the time (with a constan...
@jamespa Thanks for the feedback, the pipe work is 22mm to the airing cupboard where the hot water tank is situated, and then disappears off into in...
Just read this excellent RHH article that suggests a good solution Heat pumps that support a variable or adjustable delta T (dT), for example 7 ...
I’ve thought about the pipework and flow rate issues from first principles and tried to work out what will happen as follows: Basics 1 Kg of wate...
Post by: @old_scientist The first thing I would say is don't get too hung up on matching radiator output exactly to the room heat loss - heat will ...
@kilgorexv There is a simple rule of thumb by Michael De Podesta that is: Heat loss = Annual gas usage x Design temperature difference / 57.3 Fo...
I agree that the close alignment of the theoretical and practical heat loss calculations that I did for my house may be rather fortuitous. However,...
Thank you all for the positive comments. I have made a simple spreadsheet that implements the practical heat loss calculation that I hope will be of...
There is another estimator that you could use, a formula from Michael De Podesta's , which is simply annual gas usage divided by 57.3 multiplied by th...
@kilgorexv I think you are missing something in your heat loss calculations - the effect of thermal bridging. Thermal bridging is when you have joins ...
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RE: Next steps on my ASHP journey: Radiators and Pipework
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RE: Is it the house or the equipment?
@springswood Gas connection / disconnection is the re...
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RE: Starting Our Heat Pump Journey: 1962 build 3 bed detached house
@ian-s One interesting difference between your two q...
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RE: Siting of the external sensor on a heatpump
@jamespa Absolutely. Even if the same mistake was mad...
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RE: Recommendations in Ely (Cambs) area for Full setup checks on Nibe HP setup for House.
In fairness all heating has cost a lot to run in recent...
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RE: Navigating the World of Refrigerants In Heat Pumps: A Guide for Homeowners
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No, but the heat pump must be capable of delivering a S...
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RE: Two heating zones to one zone
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