Air Source Heat Pumps

richardc1983

We have been at 4C today and internal temps are 22C throughout, nice and cosy, just bumped the lounge upto 23C for the night...

Temps dropping and already 1.8C here in Leeds.

What heat pump do you have Andy?

Andy_WSM

richardc1983 wrote: »

We have been at 4C today and internal temps are 22C throughout, nice and cosy, just bumped the lounge upto 23C for the night...

Temps dropping and already 1.8C here in Leeds.

What heat pump do you have Andy?

Trianco Activair (Air to Water) - I've posted details somewhere in this thread.

I have it heating a tank of water and 5 radiators (2 of which are doubles).

I leave it on 24/7 and it cycles happily. Each of the radiators has it's own programmable thermostatic valve, so different temps in different rooms at different times of the day - i.e. bedrooms heated in the evening & at night, lounge first thing in the morning and during the evening.

System has been in for a year now. My heating bills have fallen on their !!! and the house is lovely and comfortable.

richardc1983

I like the idea of programmable thermostatic valves for the rooms, a very good idea... did they cost you much?

What temperature is your system able to work down to most are ok down to -15 reason I say is how do you maintain heat when temps fall below freezing?

stevehead

Andy_WSM wrote: »

Plymouth got up to 10C today?!

We struggled to 3C here in Weston-Super-Nightmare and my heat pump has struggled as a result. It's still maintained the temperature today, but used an extra 5KW/h of power to do so.

Yeah - what a difference 100 miles makes. I did my 'O' Levels in WSM and I remember snow & frosts were the norm. I also lived in Ross-Shire in Northern Scotland for a couple of years, and I would not describe the winter climate as mild.
We started at 10C, now at 9C (18.30 Fri) and just caught the forecast for 5am tomorrow will be 6C. I do keep an eye out for the temp falling below the magical 7C but been rare so far this year. It's that Cardew's fault - worrying me that once we drop > 7C I might as well switch my G Rated GSH back on.
Looks like it's due to get proper chilly next week - stay toasty!

Andy_WSM

richardc1983 wrote: »

I like the idea of programmable thermostatic valves for the rooms, a very good idea... did they cost you much?

What temperature is your system able to work down to most are ok down to -15 reason I say is how do you maintain heat when temps fall below freezing?

Stats from here: http://www1.conrad-uk.com/

There are 3 on the site: Part number 616100-LN these are the ones I have @ £29.95ea

615952-LN @ £34.95
560606-LN @ £39.99

The coldest it has been here since I have had the heat pump is -7C and it continued to work, although ran continuously, so won't have been particularly efficient I wouldn't have thought.

mech_2

stevehead wrote: »

Yes Mech, very little difference.... on the Kelvin scale!
Like today at 9am
Edinburgh - 0C
Plymouth - 10C

It's differences in this crucial range that will affect the effective COP of an ASHP system.

I think you're confusing climate and weather. I have just looked at temperatures in the evening when people are most likely to have their heating on. Plymouth and Edinburgh were back to within 2 degrees of each other.

stevehead

mech wrote: »

I think you're confusing climate and weather. I have just looked at temperatures in the evening when people are most likely to have their heating on. Plymouth and Edinburgh were back to within 2 degrees of each other.

mech I'm saying the reason my ASHP performs so well is because Plymouth's climate is much milder than UK average. You're as far from me as Spain is - still the same climate?
It's important because for the 1.5 million people who live in SW England the advertised COP performance can be achieved throughout most of the winter delivering bargain running costs. For the other 60 million of you, the results will inevitably be worse.

richardc1983

HAHA we are at 2C here in Leeds now it really is cold on an evening now, during the day though its pleasant at around 9/10 last few days.

stevehead

richardc1983 wrote: »

HAHA we are at 2C here in Leeds now it really is cold on an evening now, during the day though its pleasant at around 9/10 last few days.

and I'm at 8C now.
Rich how do you tell if your units are in defrost - like - do they indicate by flashing an led or something?

richardc1983

I can tell when its going to go into defrost as the air suddenly starts to blow cold and then the fan stops rotating pretty much like when you first turn it on and you have to wait for the coil to heat up before air blows.

There is also a green light on the front that either indicates thermostat off or defrost.

You can also hear the refrigerant circulating still when its like that and the coil starts to frost over inside when its gone into defrost outside.