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6 Red Flags to Avoid When Considering a Heat Pump Installation
@jamespa it is a good idea, but not easy as you say. We actually have something along these lines scheduled in for recording next week Friday for the podcast.
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This article highlights important factors to consider when installing a heat pump. Identifying red flags, such as poor sizing, improper installation, and lack of maintenance plans, ensures you avoid costly mistakes and achieve optimal system performance.
Posted by: @gt22If I had a new ASHP installed I would still have to have a hot water cylinder. I watched the relevant video on this site. But I don't need any buffer unit.
Can I get clarification on this point.
Can the ASHP External unit, supply heat for Central Heating radiators or UFH at one temperature and one set of F&R pipes and do that supply directly? Bypassing the cylinder?
Or have I got that completely wrong and need to go away and do some serious reading? 🤔
Posted by: @nogotonyPosted by: @gt22If I had a new ASHP installed I would still have to have a hot water cylinder. I watched the relevant video on this site. But I don't need any buffer unit.
Can I get clarification on this point.
Can the ASHP External unit, supply heat for Central Heating radiators or UFH at one temperature and one set of F&R pipes and do that supply directly? Bypassing the cylinder?
Or have I got that completely wrong and need to go away and do some serious reading? 🤔
The ASHP, just like a boiler, can supply water at only one temperature at any time. So it switches between space heating and DHW. There will be one set of F&R from the heat pump, which splits into two sets at a diverter valve.
The reason that boilers (as we set them up in the UK) can do both simultaneously is that they run the heating at a high flow temperature, resulting in both reduced comfort and a 10% increase in energy consumption and therefore cost. Boilers, like heat pumps, are actually best run at a low temperature with weather compensation (best both for comfort and cost!), but in the UK we rarely do this, unlike some more enlightened countries in mainland Europe.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
Read your Red Flags with interest. Presently tweaking my system and getting the flow temperatures down as for the past 8 yrs It has been set at 50c
Currently adjusted lockshield valves to balance the Rads and brought the flow temps down to 44c without realising musch difference . I notice you suggest 38c which is quite low to what I have had it set but willing to try.
Can I ask what flow speed can my system run at , I notice there is a graduated glass viewing setting.
I also have a buffer tank in the system which I have only discovered from this forum may not be needed . However its there and reluctant to change , due to cost.
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Hypothetical House Design
1 month ago
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Why Buffer Tanks & Low-Loss Headers Can Sabotage Your Heat Pump's Efficiency
6 months ago
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