Air Source heat Pump

[steveR]

I was seriously looking at it for a new build until I talked to a few plumbers who all said it's great but make sure you have oil back up!!!!?

And not allowed under RHI rules surely? Certainly the case with my GSHP setup. I've long said we need a small LPG backup boiler secreted in a nearby shed for power cuts or breakdowns.

My installer said it is "possibly" OK as long as there are no actual connections to the GSHP setup... As in a few carefully placed valves However, as I understand that inspections are taking pace on some installs now*, maybe I'll wait until the RHI is finished, as problems (touch wood) have so far been few and far between...



* Pablo will know i am sure...

 

[akaPABLO01]

And not allowed under RHI rules surely? Certainly the case with my GSHP setup. I've long said we need a small LPG backup boiler secreted in a nearby shed for power cuts or breakdowns.

My installer said it is "possibly" OK as long as there are no actual connections to the GSHP setup... As in a few carefully placed valves However, as I understand that inspections are taking pace on some installs now*, maybe I'll wait until the RHI is finished, as problems (touch wood) have so far been few and far between...



* Pablo will know i am sure...

There should be no need for a secondary heat source, non whatsoever.

Size correctly and reap the benefits of systems that use grid energy.

Back in the 60’s heat pumps were proposed as a heat system, problem is the power they need. A typical domestic has 100amp, a gshp may need 60amp to heat the property. Now I think 3 phase will become norm in new network designs. This is what will slow the rollout. Heat pumps are the bests heat delivery source.

Heat pumps work, no back up needed.

 

[f0ster]

it is allowed to have an oil backup as long as it is decentralized, you have to hydraulically isolate both boilers with an electronic valve such as a two port valve in the flow from each boiler so that which ever one is running the other is hydraulically isolated. so as not to feed back to a heat meter if commercial,

 

[akaPABLO01]

it is allowed to have an oil backup as long as it is decentralized, you have to hydraulically isolate both boilers with an electronic valve such as a two port valve in the flow from each boiler so that which ever one is running the other is hydraulically isolated. so as not to feed back to a heat meter if commercial,

But why would you need to?

 

[steveR]

There should be no need for a secondary heat source, non whatsoever.

Size correctly and reap the benefits of systems that use grid energy.

Back in the 60’s heat pumps were proposed as a heat system, problem is the power they need. A typical domestic has 100amp, a gshp may need 60amp to heat the property. Now I think 3 phase will become norm in new network designs. This is what will slow the rollout. Heat pumps are the bests heat delivery source.

Heat pumps work, no back up needed.

I have no argument with the statement that heat pumps work.... They can also break down and have problems like most bits of kit!

I have been delighted with my GSHP since it was installed in 2011, admittedly (as we were told) it took 12 months to get setup properly for round year usage. That said we have had the odd breakdown with it and also the odd power outage, both of which required alternative heating. Last time, we had no HP for nearly a week as my engineers waited for a soft start to arrive. Granted, we had a heatsource from the 3KW immersion heater, but once the under floor heating started to draw as well... not good for the meter!

My argument is that for a heatpump to work well, you need a modern level of insulation in the property and possibly UFH (we have this) and quite often, this type of build will mean no alternative sources of heating in the house (I fitted a small wood burner in one room) is convenient.

Happily, our grid supply is now much more resilient than it was 20 years ago as I have worked with the DNO to improve the problem areas, such as putting lines underground and their removing a problem length of ageing underground cable. Both the houses I have built have a change over switch and cabling to allow a gennie to be fitted and running in minutes. Happily the newer one has only run on gennie power a few times since we built it... BUT, and here lies the issue, the house will run happily on a small couple of kilowatt gennie, BUT the GSHP, needs a big old kick to fire it up... My argument is that a small LPG combi runs on about 120watts including the pump... so run the output from that into my buffer and storage tank, and we are good to go for a few days. My old property, would run the LPG combi off a 12v battery and inverter!

 

[akaPABLO01]

I have no argument with the statement that heat pumps work.... They can also break down and have problems like most bits of kit!

I have been delighted with my GSHP since it was installed in 2011, admittedly (as we were told) it took 12 months to get setup properly for round year usage. That said we have had the odd breakdown with it and also the odd power outage, both of which required alternative heating. Last time, we had no HP for nearly a week as my engineers waited for a soft start to arrive. Granted, we had a heatsource from the 3KW immersion heater, but once the under floor heating started to draw as well... not good for the meter!

My argument is that for a heatpump to work well, you need a modern level of insulation in the property and possibly UFH (we have this) and quite often, this type of build will mean no alternative sources of heating in the house (I fitted a small wood burner in one room) is convenient.

Happily, our grid supply is now much more resilient than it was 20 years ago as I have worked with the DNO to improve the problem areas, such as putting lines underground and their removing a problem length of ageing underground cable. Both the houses I have built have a change over switch and cabling to allow a gennie to be fitted and running in minutes. Happily the newer one has only run on gennie power a few times since we built it... BUT, and here lies the issue, the house will run happily on a small couple of kilowatt gennie, BUT the GSHP, needs a big old kick to fire it up... My argument is that a small LPG combi runs on about 120watts including the pump... so run the output from that into my buffer and storage tank, and we are good to go for a few days. My old property, would run the LPG combi off a 12v battery and inverter!

Maybe a log burner would complement, it’d certainly be cheaper then lpg?

Just got back from a gshp issue, needless to say customer had left the filling loop on whilst topping up the array diluting the antifreeze. Return temperature-17.1° lol. Pretty cold. Amazing to see compressors extracting 13° from 4° flow.

Still though, locked out with the dilution, need to order more.

Lesson learnt.

 

[f0ster]

We have installed lots of systems where the customer already has a good oil boiler and does not want to scrap it. So all it requires is a couple of two port valves to provide isolation and a change over switch.

 

[akaPABLO01]

We have installed lots of systems where the customer already has a good oil boiler and does not want to scrap it. So all it requires is a couple of two port valves to provide isolation and a change over switch.

Jeez.

Like strapping a 2 stroke mower engine on a Tesla car “just” in case we need it.

 

[steveR]

Maybe a log burner would complement, it’d certainly be cheaper then lpg?

Just got back from a gshp issue, needless to say customer had left the filling loop on whilst topping up the array diluting the antifreeze. Return temperature-17.1° lol. Pretty cold. Amazing to see compressors extracting 13° from 4° flow.

Still though, locked out with the dilution, need to order more.

Lesson learnt.

Ooops!! An expensive mistake....

From my perspective, a log burner is often a focal point and focal heat. It's not a lot of use when the room you WANT to sit in is at the other end of the house! The idea behind a small LPG boiler, is that you can utilise the existing UF heating and hot water systems, just switch over to LPG heat IF we have a power outage or a heat pump problem.

 

[steveR]

Jeez.

Like strapping a 2 stroke mower engine on a Tesla car “just” in case we need it.

ROFL!!

 

[Glomulinman]

Surely livestock sheds are warm in the winter, could we not use that heat?

 

[Exfarmer]

Surely livestock sheds are warm in the winter, could we not use that heat?

You certainly can. A lot of broiler houses use heat pumps to recycle the heat.

 

[Grassman]

Surely livestock sheds are warm in the winter, could we not use that heat?

I had a customer with a remote block of stables who laid a blue polypipe through a muckheap she has for horses. Turn on the tap and warm water comes out. Better than freezing cold water and no frozen hose pipe.

 

[Puff]

How about a wood burning stove with a back boiler? Feed it to a heat store and then that can pass it around the rest of the house as necessary.

 

[Speedstar]

Jeez.

Like strapping a 2 stroke mower engine on a Tesla car “just” in case we need it.

So what would recommend for new build 170 s/m Bungalow , ? , how many meters of pipe do you need to put in the ground ?, would you put any solar panels on the roof ?

 

[Mur Huwcun]

So what would recommend for new build 170 s/m Bungalow , ? , how many meters of pipe do you need to put in the ground ?, would you put any solar panels on the roof ?

Don’t you have to have some sort of renewable energy in every new built now? Every new build around here have solar oanels or GSHP or both. If you have the land definitely go fir GSHP in a new build and insulate like mad. The RHI will pay for the install, the underfloor install, the plumbing and the electricity bill for the 7 yrs plus spare!!!

 

[Speedstar]

Don’t you have to have some sort of renewable energy in every new built now? Every new build around here have solar oanels or GSHP or both. If you have the land definitely go fir GSHP in a new build and insulate like mad. The RHI will pay for the install, the underfloor install, the plumbing and the electricity bill for the 7 yrs plus spare!!!

So with GSHP will you need a boiler to have the house nice and warm as well to heat the water for the under floor heating if it gets down to -20 ?

 

[24/7 farming]

So with GSHP will you need a boiler to have the house nice and warm as well to heat the water for the under floor heating if it gets down to -20 ?

Nope, no backup required, pipes 4-5 ft underground so never reach - 20 down there, good installation in the house is critical tho if at those temps, we've got as low as - 8 for a few days and the house would drop 2 degrees over the day, that was with the heating only running at night, I would imagine if it had got any colder it would have had to run a bit during the day to top it up too.
I have 600m of pipe in the ground for a 250sqm house, would have got away with 500 but had the space

 

[Courier]

Beware quotes from installers without knowing the temperature at which the efficiency ratio was quoted.
In mild winter weather they are ok but as the temp drops so does the efficiency. In cold weather you can be down to 2:1 or less so it's not so cheap. Need to work out on average figures for monthly temp to get true costs.
I was seriously looking at it for a new build until I talked to a few plumbers who all said it's great but make sure you have oil back up!!!!?

Had ours ASHP running for two winters now, I had underfloor wet system installed when I built the house in 1995 and never worked well on oil.

The underfloor pipes are in a 3" screed directly over 4" oversite mass concrete over 2" of insulation with a 2" thermal break around it.
Biggest problem is overheating after a prolonged freezing spell because of the heat build up in the slab.....

Couldn't see it working well with radiators unless they were specced for 55 degree water.

 

[Speedstar]

Nope, no backup required, pipes 4-5 ft underground so never reach - 20 down there, good installation in the house is critical tho if at those temps, we've got as low as - 8 for a few days and the house would drop 2 degrees over the day, that was with the heating only running at night, I would imagine if it had got any colder it would have had to run a bit during the day to top it up too.
I have 600m of pipe in the ground for a 250sqm house, would have got away with 500 but had the space

Is it heavy on electric an do you run it off 3 phase ? ,Any solar panels ?