The heat pump I'm sure is OK in so much as it's working as intended but whether it can chuck out sufficient heat at your operating conditions is what you need to find out. Do you know what your flow temp is?
- Thread starter Welderpaul
- Start date
gaz1
Member
- Messages
- 19,440
- Location
- westyorkshire
have they been out when its hit cold temperatures like it is now ?
and if they have what have they said then ?
- Messages
- 14,562
- Location
- UK
They tested it last year, temperatures at the time were similar to the cold spell we have now.
How do i find out the flow temperature?
How do i find out the flow temperature?
I haven't used the grant one but does it not tell you on the display? Failing that download the installation guide from the net on page 34 it shows the weather compensation parameters. If you can get to these in the menu we will be able to see the parameters and work out the flow temp.
DAPPH
as dyslexik as I'm daft
- Messages
- 7,389
- Location
- Near to Cross Hands Llanelli SouthWales GB
Can you pipe /cowl an insulated air pipe in from a below ground tunnel to get the air in at a better temp. Whilst it's 10 oC or 50 oF at 2 mtrs below ground , even a slabbed over well constructed deep trench might give you the required higher inlet temp in very cold weather .
The very much out in the sticks people where the owner of the alarm company I worked for fitted the hard prewired alarm system in to their now occupied new build that they had moved into 3 months earlier in Feb 1982 .
They had their ASHP 35 mtrs away down the garden with well insulated pipe work which was fitted was in a 2x2x4 foot deep concrete trench that had removable sealed slabs over the top ( doubled as a garden path way too ) .
They drew the ASHP air source from within the trench .
It was minus 18 C when we visited , with over foot of snow on the ground for over three weeks , The householder said that whilst they had an oil fired back up central heating with rads they'd not had need to use it so far, as the blown air was coping very well
They got visited because at minus 18oC a lot of the battery back up sustained alarm bell boxes failed due to the extreme cold and went into alarm. Muggins here had to go up the ladder and fit a heated module in the boxes . Kin cold indeed .
,
The very much out in the sticks people where the owner of the alarm company I worked for fitted the hard prewired alarm system in to their now occupied new build that they had moved into 3 months earlier in Feb 1982 .
They had their ASHP 35 mtrs away down the garden with well insulated pipe work which was fitted was in a 2x2x4 foot deep concrete trench that had removable sealed slabs over the top ( doubled as a garden path way too ) .
They drew the ASHP air source from within the trench .
It was minus 18 C when we visited , with over foot of snow on the ground for over three weeks , The householder said that whilst they had an oil fired back up central heating with rads they'd not had need to use it so far, as the blown air was coping very well
They got visited because at minus 18oC a lot of the battery back up sustained alarm bell boxes failed due to the extreme cold and went into alarm. Muggins here had to go up the ladder and fit a heated module in the boxes . Kin cold indeed .
,
addjunkie
Member
- Messages
- 12,971
- Location
- Northumberland. Reet oot in the sticks
Grant do a nice airsource heat pump that gets you the rhi or what ever. You can then get an extension oil boiler fits on the side for when its really cold. Say-it all really.
Does your system use a thermal-store too, if so some have additional electric heating fir when the system is inefficient
Does your system use a thermal-store too, if so some have additional electric heating fir when the system is inefficient
mtt.tr
Member
- Messages
- 8,437
- Location
- Essex/Suffolk border
This guy is to be taken with a bucket of salt, he has opinions never facts.
For instance he was schooled by a damp expert then proceeded to ignore what was said.
He's basically becoming a dinosaur,heat pumps properly specd are more than capable.
paul have you checked your house for heatloss?
- Messages
- 14,562
- Location
- UK
I have a suspicion that the over riding issue here is that air source heat pumps are generally cr@p when the outside temps are zero, or thereabouts. 
I read the below or similar time and time again on t'internet.
I read the below or similar time and time again on t'internet.
mtt.tr
Member
- Messages
- 8,437
- Location
- Essex/Suffolk border
I have a suspicion that the over riding issue here is that air source heat pumps are generally cr@p when the outside temps are zero, or thereabouts.
View attachment 376273
Scandi nations and US seem to make them work in low temps.
- Messages
- 14,562
- Location
- UK
There is an immersion in the side of the cylinder, but that's about it
Farside
Badly Welded Man
- Messages
- 5,938
- Location
- Ireland
Scandis have a voot of insulation on the walls and two veet in the roof.
mtt.tr
Member
- Messages
- 8,437
- Location
- Essex/Suffolk border
This is the issue we dont, the argument often spouted is "get a gas or oil boiler" this is like putting a plaster on a gun wound
addjunkie
Member
- Messages
- 12,971
- Location
- Northumberland. Reet oot in the sticks
Yes but is that a hot water tank, or a thermal store. A thermal store increas3s the water volume in the wet side of the system increasing its efficiency. But adding extra heat to this store, solar pv economiser thing, or plain emersion takes load of the heat pump.
- Messages
- 14,562
- Location
- UK
Right ok, in that case no i don't have a thermal store.
- Messages
- 13,471
- Location
- England
I have a suspicion that the over riding issue here is that air source heat pumps are generally cr@p when the outside temps are zero, or thereabouts.
View attachment 376273
I'm under the impression heat pumps are much more efficient for underfloor heating rather than radiators.
Perhaps add a supplementary heat source for when it's brass monkeys.
Whilst not the cheapest things to run, maybe an electric boiler could be integrated fairly simply. The advantages being no flue, no servicing... take up minimal space.
Mines been in 4 years, never had to touch it yet.
Kram
Member
- Messages
- 7,447
- Location
- Sussex
9.1kw / 2.66 (COP) gives a motor power of 3.4kW. I'd say thats very undersized, but I've never used or worked with one... Just from the numbers. Now if the motor was 9kw I think that would be quite decent...
Water has a very high specific heat, your asking this heat pump with little more power than a kettle, to heat your water for heating and water with a huge thermal mass, and this will limit how hot it will get. (1watt/joule =1c per cc per second)
Water has a very high specific heat, your asking this heat pump with little more power than a kettle, to heat your water for heating and water with a huge thermal mass, and this will limit how hot it will get. (1watt/joule =1c per cc per second)
mtt.tr
Member
- Messages
- 8,437
- Location
- Essex/Suffolk border
Assuming you are not leaking huge amounts of heat low temp rads are adequate.
- Messages
- 14,562
- Location
- UK
Literally every source tells me it's correctly sized for the size of the house. If it had been too small, whilst being expensive, that would have been an easy fix to the problem.
