Stop pushing heat pumps or face major backlash, Dale Vince tells Labour

[Ken]

I have a few issues with HPs.

I would fit 1or 2 A2A HP but my wife will have non of it, citing the draught and looks of the indoor unit

I would fit a A2W system but my house is small bore

I dont agree with the MCS that the whole house should be heated to 21C ? on the coldest day of the yr. This makes for a bigger and more expensive and probably less efficient system. At this time of the yr i allow my body to acclimatise to the colder weather. My house temp is 18-19C today but will be down to 17C in coldest winter. I am not interested in having a heating system that by itself caters for the say 10 coldest days.

I dont care if a HP with my tank cant get the water to 60C+ as i only need it to get to 39C for a shower. If the HP cannot get to that the extra energy required from an immersion heater or my favorite solution a inline heater (electricity modulating) is extremely small.
When i run the HW at 40C ish then the total energy used is 1/2 that of having the water at 60C + The heat losses in most HW systems with a tank is over 50%

[Fintray]

Hi Ken

Your post states that you have a few issues with heat pumps but then doesn't mention any of them only other blocking issues towards getting one.

[Ken]

Hi Fintray,
Thats true but you probably were expecting tech issues of which there are non IMO.
They are however being blocked by other real ISSUES - be they Money, house space,house disruption, size of pipes/rads and....

[Fintray]

Hi Fintray,
Thats true but you probably were expecting tech issues of which there are non IMO.
They are however being blocked by other real ISSUES - be they Money, house space,house disruption, size of pipes/rads and....

The disruption mostly due to microbore piping/rads having to be replaced is definitely one that puts people off having a HP fitted.

[HML]

I have a few issues with HPs.

I would fit 1or 2 A2A HP but my wife will have non of it, citing the draught and looks of the indoor unit

I would fit a A2W system but my house is small bore

I dont agree with the MCS that the whole house should be heated to 21C ? on the coldest day of the yr. This makes for a bigger and more expensive and probably less efficient system. At this time of the yr i allow my body to acclimatise to the colder weather. My house temp is 18-19C today but will be down to 17C in coldest winter. I am not interested in having a heating system that by itself caters for the say 10 coldest days.

I dont care if a HP with my tank cant get the water to 60C+ as i only need it to get to 39C for a shower. If the HP cannot get to that the extra energy required from an immersion heater or my favorite solution a inline heater (electricity modulating) is extremely small.
When i run the HW at 40C ish then the total energy used is 1/2 that of having the water at 60C + The heat losses in most HW systems with a tank is over 50%

Microbore doesn't stop you installing a heatpump.



claims to have used microbore and produced an efficient system. It depends on the particular system, but short runs of narrow pipe to the radiators with a bigger backbone should work reasonably well.

When I installed my system I replaced most of the feeds with 15mm but one radiator wouldn't have looked good so I used the old 8mm microbore. It works OK.

Although I'm not a fan of MCS, designing the system to heat to 21C is sensible. The next owner of your house might have more normal temperature expectations, it's not a good idea to install a system which isn't capable of providing acceptable temperatures. Of course you don't need to use an MCS fitter so you can design the system as you wish. I didn't use MCS for mine.

Our HW is heated to 47C, any lower and the hot water is likely to be tepid before the next reheat. No legionella cycle. It uses 1.5-2kWh a day.

[Ken]

Yes i can see that but i have small bore all the way and buried in concrete. For many, as I, the problem will be made worse by the fact that with high temp boiler flows the length of individual pipes from the manifold is not that critical but sure can imagine it critical at HP flow rates and temps and thats before some of the legs will have more than one rad on it. Thats just what they did backalong.

With small bore pipes unless very short, the flow rates cannot be achieved that one needs for adequate efficiency. Sure one can up the temp to compensate for low flow rate but this wiil give too big a temp difference across the HP and lead to significant inefficiency.

[Ken]

I have a few issues with HPs.

I would fit 1or 2 A2A HP but my wife will have non of it, citing the draught and looks of the indoor unit

I would fit a A2W system but my house is small bore

I dont agree with the MCS that the whole house should be heated to 21C ? on the coldest day of the yr. This makes for a bigger and more expensive and probably less efficient system. At this time of the yr i allow my body to acclimatise to the colder weather. My house temp is 18-19C today but will be down to 17C in coldest winter. I am not interested in having a heating system that by itself caters for the say 10 coldest days.

I dont care if a HP with my tank cant get the water to 60C+ as i only need it to get to 39C for a shower. If the HP cannot get to that the extra energy required from an immersion heater or my favorite solution a inline heater (electricity modulating) is extremely small.
When i run the HW at 40C ish then the total energy used is 1/2 that of having the water at 60C + The heat losses in most HW systems with a tank is over 50%

Microbore doesn't stop you installing a heatpump.



claims to have used microbore and produced an efficient system. It depends on the particular system, but short runs of narrow pipe to the radiators with a bigger backbone should work reasonably well.

When I installed my system I replaced most of the feeds with 15mm but one radiator wouldn't have looked good so I used the old 8mm microbore. It works OK.

Although I'm not a fan of MCS, designing the system to heat to 21C is sensible. The next owner of your house might have more normal temperature expectations, it's not a good idea to install a system which isn't capable of providing acceptable temperatures. Of course you don't need to use an MCS fitter so you can design the system as you wish. I didn't use MCS for mine.

Our HW is heated to 47C, any lower and the hot water is likely to be tepid before the next reheat. No legionella cycle. It uses 1.5-2kWh a day.

That video was using 22mm distribution pipes under the floor boards - thats not small bore.

[AGT]

I have a few issues with HPs.

I would fit 1or 2 A2A HP but my wife will have non of it, citing the draught and looks of the indoor unit

I would fit a A2W system but my house is small bore

I dont agree with the MCS that the whole house should be heated to 21C ? on the coldest day of the yr. This makes for a bigger and more expensive and probably less efficient system. At this time of the yr i allow my body to acclimatise to the colder weather. My house temp is 18-19C today but will be down to 17C in coldest winter. I am not interested in having a heating system that by itself caters for the say 10 coldest days.

I dont care if a HP with my tank cant get the water to 60C+ as i only need it to get to 39C for a shower. If the HP cannot get to that the extra energy required from an immersion heater or my favorite solution a inline heater (electricity modulating) is extremely small.
When i run the HW at 40C ish then the total energy used is 1/2 that of having the water at 60C + The heat losses in most HW systems with a tank is over 50%

You get units that fit at radiator level too, if the high level unit offends

[HML]

That video was using 22mm distribution pipes under the floor boards - thats not small bore.

The radiators were fed with micro bore pipes. It's a common arrangement.

Obviously if the system has a manifold and 10s of metres of microbore feeding each radiator then it isn't going to work well, but it probably didn't work well with a gas boiler either.

[Mart]

What would be a 'microbore issue'? My system has 28mm (I think) pipework, but each radiator is fed/returned to the main pipes by 10mm microbore. Perhaps 2m runs to the rads (some a bit less, some a bit more).

Given that our rads are now oversized, as heat demand has fallen over the years, and I've been running the boiler radiator temp at its lowest (out of curiosity), I assume my system could cope with an ASHP. Or at worst a HT ASHP, so a lower COP during the periods when higher temps are needed?