Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
The good, the bad and the not that great – my heat pump installation
Regarding the w/machine its very odd that the hot water is high pressure but there isnt sufficient pressure to fill the machine.
I suspect it's a "Cold Fill" only machine.
Me too, but either the cold fill is fed from the 'mains' (actually water from a well) or its fed from cold outlet of the inlet group to the DHW tank, which will be at the same pressure as the DHW. The former must (presumably) be higher pressure than the latter and OP says he has problems with too much water pressure on the hot.
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.
@jamespa DHW - direct hot water? Large tank labelled Kodiak? Or should I be looking for another tank. Know most of old, rather agricultural, plumbing was removed and presumably replaced.
@jamespa Know most of old, rather agricultural, plumbing was removed and presumably replaced.
Ah, that may account for increased pressure in the hot water. This would be described as a 'upgrade'!
Transparent and I now agree what the grey valve/filter does so you can use either approach to reduce hot water flow (but I would just try the lever valve first - its the simplest by far!)
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.
This graphic is mainly for @jamespa and I to chew over, and particularly the pipe I've annotated in light purple.
The only question for @dwynwen is to clarify if the pipe labelled in light green is connected to anything. We can't see that in the photos.
Note to James: I too have a well.
That means my house has several different pipes which carry cold water.
To ensure that cold water being fed to the showers and bath is at the same pressure as the hot supply, I have one cold pipe-network which gets fed from the same pressure adjustment valve as feeds into the hot tank.
Is it possible that the installer has used the 'wrong' cold supply pipe in @dwynwen 's house?
Is that why he's seeing pressure differential when there shouldn't be any?