Air Source Heat Pump - is it connected to the water supply?

28 Oct 2008
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United Kingdom
I am currently planning a new house (for me) with underfloor heating powered by an air source heat pump. The heat pump will be installed by a professional but I am trying to understand how it is all going to work.

The circuit from the heat pump will go to the hot water cylinder or the UFH buffer tank, depending on what the controller is telling it to do. This is effectively a closed circuit. Does there need to be a connection to the cold water supply somewhere (presumably with some sort of stopcock) to allow the system to be re-pressurised if necessary?

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should be a filling loop somewhere I would think.. how else are you going to get the water in it in the first place?
how else are you going to get the water in it in the first place?
I was reading some instructions about pressure testing the underfloor heating circuits and it explained how to fill them up through the ends of the manifold. Given that they are on the same closed circuit, this sounds like it ought to fill the whole system but it doesn't sound like a good long term solution!
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all you need is a cold water mains feed with a valve on it, a length of braided hose with another valve on it, and then connect that to the cold water in feed. open the street side valve first the gradually open the heating side valve until you reach pressure. Close both valves and hey presto. You may want to put a pressure regulator on you mains feed to prevent the system going over pressure the second you open both valves. Rinse and repeat after bleeding the system to obtain correct operating pressure. Hope that helps.

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