Air Source Heat Pumps

Baz@rr

Thanks for the replies. I'm not over at the house at the moment, but will reply with more info when I am. What I can tell you at the moment is that it's a Grant Aerona pump (HPAW110 I think, but will confirm later) feeding radiators in all the rooms and UFH in the bathrooms.

The system has been running constantly for the past few weeks (thankfully not at my expense) so it isn't in the process of warming up.

I'm not sure how to get a reading on what temp the system is trying to bring the water up to, although there's a little control panel in the garage not far from the pump which seems to flit between 40deg and 42deg of its own accord.

There is one thermostat that I can see, which is in the downstairs hall and which is set to about 21deg. There are other stats outside the bathrooms for the UFH, but that seems to be off at the moment, which may be just as well as I'd imagine it'd bump the cost up further?

lovesgshp

Have no knowledge of that pump to be honest. 21C is a high temp and if the readout is saying 40 - 42C that is low for radiators ( that would explain the long running times). It would normally be circa 50 - 55C. My opinion is that the setting is wrong, but quite happy to be corrected.
Is there a buffer tank which compensates for the UHF and the rads?

Baz@rr

I've had a quick look outside the house and the pump only outputs 8.73kW which seems low?

There's a "Grant Duowave heat pump cylinder" in the big cupboard where the controls are. That has a little thermostat on it which is set to about 40deg.

My understanding is that when the system is switched to timed mode the pump should only kick in when within the times I've set for the heating to come on. Or is that wrong? Does the pump run regardless of this?

lovesgshp

What is the sq mtrs of the house?
If the cylinder is only set to 40C then it could mean it has been left on a antifrost type cycle.
As I say I am a little in the dark on this system, as could not pull up the technical manual, which may have helped a little more, so some things I am stabbing in the dark at, so my answers may be out.

Baz@rr

I'll have to check on the house size, but I can help you with the manual. Second link under technical manuals on this page. https://www.grantuk.com/downloads/air-source-heat-pump-downloads/

lovesgshp

Thanks, I clicked on the addendum. Will have a read and see if I can help

lovesgshp

Baz@rr wrote: »

I'll have to check on the house size, but I can help you with the manual. Second link under technical manuals on this page. www.grantuk.com/downloads/air-source-heat-pump-downloads/

On page 11 of the manual, can you post your readings?

lovesgshp

Looks like the duowave cylinder may be connected at a lower temp than needed.

Baz@rr

Geotherm wrote: »

On page 11 of the manual, can you post your readings?

Page 11? Or do you mean section 11 (page 31)? If so, they match those, except Max defrost cycle is 10mins rather than 8.

lovesgshp

Page 32. Need to see the settings
Sorry, was section 11