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Last seen: Sep 14, 2026
@jamespa Thanks, you are right. I needed to look at this again. At worst the flow splits into two parallel 15mm pipe runs. I am convinced that as...
@old_scientist If you fall below the minimum flow rate, most ASHPs will simply throw a flow rate error and switch off until the flow rate is increa...
When we first moved into the house, it had single glazing, cavity wall insulation, and about 150mm of loft insulation. If I take all the upgrades out ...
Posted by: @cathoderay All I am doing is emphasising the point that the long term averages used to calculate the HTC must be based on frequent enou...
Posted by: @jamespa Whilst I don't like determining things based on a single measurement point because you don't have a tool to spot errors, I also...
@cathoderay @ian33a The way the calculation works is to determine the Heat Transfer Coefficient (HTC) - the total energy required to keep the indoo...
@ian33a You only need the heat energy in kWh output by your heating system for 1 cold month e.g. January, along with your average indoor temperature...
@ian33a I recently did a heat loss calculator spreadsheet based on gas usage over a cold period in winter e.g. January. I'm sure you could easily ad...
@bobflux The hydraulic simulator is very interesting. I don't know if I can give you enough information to do a reasonable model of our heating sys...
Changing the 15mm pipe would be very disruptive and no doubt expensive, so I don't want to go there. As an alternative, I would be happy to compromi...
Posted by @jamespa There are a couple of possible installer parameters namely conf heat build pump, unit %pwm, default auto, but can be set 50%-100...
Post by: @robs Is the pipework the original, like the radiators? Also, your calculated pressure drops seem quite low. Thanks for the tip abo...
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Degrees of Separation
Latest Posts
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RE: Who's your electricity provider and what's your tariff?
Switch to Cosy 12 month fixed initiated - just waiting ...
By Old_Scientist , 2 hours ago
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RE: Next steps on my ASHP journey: Radiators and Pipework
If you have a flowmeter and two temperature probes, the...
By bobflux , 3 hours ago
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RE: Is it the house or the equipment?
@springswood Gas connection / disconnection is the re...
By Rob of York , 4 hours ago
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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...
By Rob of York , 8 hours ago
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RE: Siting of the external sensor on a heatpump
@jamespa Absolutely. Even if the same mistake was mad...
By Batpred , 10 hours ago
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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...
By JamesPa , 1 day ago
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RE: Navigating the World of Refrigerants In Heat Pumps: A Guide for Homeowners
Indeed we are invvestigating AC at present and are havi...
By Toodles , 2 days ago
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No, but the heat pump must be capable of delivering a S...
By JamesPa , 3 days ago
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RE: Daikin ESPAltherma and Home Assistant installation
It's laziness lol The PV system is very chatty, meter...
By bobflux , 3 days ago
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RE: Problems with sizing a replacement for a Viessmann Vitocal 200-S
R (The R Project for Statistical Computing, I use it wi...
By cathodeRay , 3 days ago
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RE: Vaillant Arotherm Plus 7KW need a service on it
booked it with Vaillant. will use them until i can find...
By AdamK , 3 days ago
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RE: Adventures in heat loss calculations
I have seen it stated that the declared calorific value...
By JamesPa , 4 days ago
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RE: Two heating zones to one zone
@transparent Many thanks. The garage is fairly well ...
By Profzarkov , 4 days ago
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