ASHP: lagging pipes in loft

gterr

jeepjunkie wrote: »

Whole house consumption at the moment is in the mid 40 units a day. Not sure of temp but our part of the country is stuck in a deep freeze with snow and hard pack frozed ice. 4wd mandatory here in the hills Also leave a 200w panel heater on in the porch say 18hrs a day which is surprisingly effective.

Hope this helps.

Hee Hee! 41 units in last 24 hours here!!!
(Mind you, this is with outside temp of about +4 C, and my upstairs rads are still off, but still.........)

Geotherm,
Thanks for the link to the meter.

lovesgshp

gterr wrote: »

Hee Hee! 41 units in last 24 hours here!!!
(Mind you, this is with outside temp of about +4 C, and my upstairs rads are still off, but still.........)

Geotherm,
Thanks for the link to the meter.

Now, now, from 60+ it's gone down :T

gterr

Geotherm wrote: »

Now, now, from 60+ it's gone down :T

Yep, quite an achievement, since it was 65 units on 2nd Dec, AND the house was chilly!
Rad timer going back on tonight. Fingers crossed!

[Deleted User]

gterr wrote: »

Hee Hee! 41 units in last 24 hours here!!!
(Mind you, this is with outside temp of about +4 C, and my upstairs rads are still off, but still.........)

Geotherm,
Thanks for the link to the meter.

Excellent

lovesgshp

jeepjunkie wrote: »

Excellent

It is looking a lot better to be sure!!

lovesgshp

Gterr.
Did you receive the documentation I sent to you by email??

gterr

Geotherm wrote: »

Gterr.
Did you receive the documentation I sent to you by email??

Hi Geotherm,
Yes I did, thanks. I did already have the installation and user manuals, but not the curves, so thanks for those.

Will report back in a few days with average usage. Whole house used 37 (!!!!) in last 24 hours, but weather mild at present: about +6 C and raining.

Just one quick question: I am happy to leave the internal temp sensor influence set to zero. Could you just confirm that with this setting in place the room temperature setting that can be set and adjusted from the top level menu on the Rego will have no effect whatsoever on the pump behaviour?

Presently have radiators on a few hours per day. May want to experiment with closing at least one of the TRVs. I don't want to cause a problem with low flow rate again, however. You know this by-pass valve that should have been installed, and which would allow us to make free with the TRVs: can these be retro-fitted? Is it a big plumbing job?

Cheers!

lovesgshp

gterr wrote: »

Hi Geotherm,
Yes I did, thanks. I did already have the installation and user manuals, but not the curves, so thanks for those.

Will report back in a few days with average usage. Whole house used 37 (!!!!) in last 24 hours, but weather mild at present: about +6 C and raining.

Just one quick question: I am happy to leave the internal temp sensor influence set to zero. Could you just confirm that with this setting in place the room temperature setting that can be set and adjusted from the top level menu on the Rego will have no effect whatsoever on the pump behaviour?

Presently have radiators on a few hours per day. May want to experiment with closing at least one of the TRVs. I don't want to cause a problem with low flow rate again, however. You know this by-pass valve that should have been installed, and which would allow us to make free with the TRVs: can these be retro-fitted? Is it a big plumbing job?

Cheers!

Ok with the internal sensor @ 0c, as is having no influence on the external unit. Glad the usage is still dropping. You are warmer than us there, as we had snow last night with the ploughs out thismorning!!
Do the experiments with the TRV's, if you find that the usage goes up by quite a lot, then it will probably be a bypass add. I am sure one of the plumbing experts on here could give you a guide price for a retrofit.

gterr

Hello again,

Third successive day of outside temps hovering just under zero. Whole house usage has been between 40 and 54 KW per day - partly dependent on what else we were using electricity for in the house. Lovely and warm, though radiators upstairs producing higher room temps than we required. Flow temp around 44 C.

Yesterday I lowered the radiator TRVs from III to II. This does seem to have adversely affected things. I could hear water circulating almost all night (pump to primary store? primary store to U/F coils??) and in the 12 hours between 9pm Tuesday and 9am today we used 32 units, virtually all on heating.

Have now opened the TRVs up to III again. They are on a timer: a couple of hours in the morning, a few hours in the evening.

Wondering what to do about the radiators now. What we'd really like is for one bedroom rad to be off all the time, second bedroom rad and landing rad to be on no higher than II, and bathroom rad on full. In the summer we don't need any heating at all upstairs, but would like the bathroom rad on to warm towels.

Our pump uses a heat curve, so flow temp of heating water depends on outside temp. The heat curve we have set is one suitable for a radiator system (higher flow temps that for a U/F system), and there's a mixing valve so that the U/F coils don't get water that's too warm.

So, it seems to me that the economy of the whole system is compromised for the sake of the rads that we hardly need, and we are limited in how we adjust these because there is no bypass valve and we mustn't impede flow to the U/F coils.

Just wondering if we should abandon the rads altogether - leave them all wide open but turn the timer off. Then set a new heat curve suitable for U/F only, which will use a lower flow temp. (Producing heating water at, say, 32 C must use less electricity that producing it at, say 45 C?). Then get a couple of halogen heaters for upstairs, and maybe get an electrical element fixed in the towel rail rad.

What do you think?

albyota

Gterr, I would advise lowering the heat curve to produce 35c this should solve the problem of the upstairs rads, however, my suspicion is that the bathroom might not get as warm as you would like so I would be inclined to fit / replace bathroom rad with a towel rail with an electric element on a 1,2, 4 hour horstman boost switch, that way you can just use the towel rail in the summer with the element for drying towels. As you quite rightly suggest lower temp=lower running costs, I have my heat pump set on weather compensation, sits mainly at 32 to 35 degrees and in the recent cold snap has automatically adjusted to 37 degrees, house is lovely and warm, I have an OWL energy monitor connected directly to the supply of the heat pump and is currently showing 1.27kW with ambient of minus 1.