Soldato
What do you think the problem with heat pumps is?
Heat Pumps: anyone have one/thought about it?
- Thread starter fish
- Start date
What do you think the problem with heat pumps is?
Re underfloor heating. Sounds like the ideal solution but could be so disruptive to install. Are the non screed systems any good?
Are there any options that don't use a hot water cylinder. Our hot water usage is very low and really don't have room for a cylinder.
Yes, but you lose 20mm in floor/ceiling height.
Not with a heat pump. If you did get a heat pump and didn't have a cylinder, you'd need a standalone solution for hot water such as an electric water heater for each outlet or central electric boiler. Alternatively, find a solution to get a cylinder into the loft space or garage if you have one. I've even seen people put them in outbuildings.
Associate
I don’t think there is a problem with them, the problem I find is the customers/end users always think the radiators should be boiling to the touch, where the system isn’t designed to go past a 55 degree flow temp as it would be inefficient and the heat-pump wouldn’t beable to get the flow temp to that without additional electric heaters to Boost it, there fore becoming inefficient
Yer underfloor heating is great if you’re installing in a New build, it is very intrusive should you install it in a existing house,
The screedless systems work well too, just still have to raise the floors by 15-20mm depending on which you go for
Heatpumps do work with radiators though, as long as your flow and return pipework isn’t microbore pipe and at least 15mm (22mm desirable then branch down)
Unfortunately no, not yet anyway, hot water is hard to heat instantly with a ASHP as it builds up the temperature over a cycle, they are inverter driven so take have a much slower heat up time compared to a normal gas boiler, they rely on water cylinder to maintain the water temperature and then ASHP will just warm it up once you use it and once it drops below a certain temperature.
Soldato
Yes, you can buy something like a Sunamp thermal battery instead, the hot water is more instantaneous than even a combi can achieve
A homeowner’s experience: why I chose a Sunamp heat battery over a hot water cylinder - Sunamp Global
By Michael Eve, homeowner with a Thermino heat battery
sunamp.com
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I've seen a house listed as "warm air heated" and noticed there's no radiators. The age of the property makes me think it might be an older gas powered one. All the carpet is 80s-90s so unless it's a recent install im thinking older gas variant.
How do heat pumps work in these systems efficiency wise Vs a wet system? Suitable to go full HVAC?
How do heat pumps work in these systems efficiency wise Vs a wet system? Suitable to go full HVAC?
Forced air heat pumps are common in the states, less so in a domestic setting here.
Forced air can do heating and cooling which is why it’s popular there. You may be able to get it retrofitted to a heat pump.
If not you’ll probably be better off using split air to air system in all the rooms you want to heat (and cool) than installing a wet system. You can get loft mounted units that can duct air to all the rooms below it so you’ll not even have visible wall units in those rooms.
Air to air is actually more efficient so it’s criminal it’s not promoted more here IMO.
Forced air can do heating and cooling which is why it’s popular there. You may be able to get it retrofitted to a heat pump.
If not you’ll probably be better off using split air to air system in all the rooms you want to heat (and cool) than installing a wet system. You can get loft mounted units that can duct air to all the rooms below it so you’ll not even have visible wall units in those rooms.
Air to air is actually more efficient so it’s criminal it’s not promoted more here IMO.
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Soldato
We have just purchased a property that was built in 2004 and the radiators look the same as the ones in our 2012,then new build, were. However all the piping looks to me like 10mm plastic. Would this be an issue?
Potentially, potentially not depending on the heat loss of the property.
It’s a 2012 property so the heat loss should be relatively low and it’s probably only 10mm to the radiators. The flow and return should be bigger.
You’ll probably just need a buffer and it will work fine but at a slightly lower efficiency. If the heat loss is significant, it may need a partial re-pipe.
The only way to know is for someone to come round and do a proper survey and design a system for your house.
The radiators will need replacing regardless. The general rule is any singles need to be replaced with double panels and and existing doubles will need to be made bigger.
Associate
Air 2 air Heatpumps, basically air-conditioning systems, I’ve fitted hundreds of these in domestic property’s, from wallmounted ones, to ducted, to floor mounted,
They are great as they heat the air up in the room quickly so you feel the benefit fast
I’ve fitted a few multi systems recently, it had 5 indoor units from one condenser outside, so they had ac in each 3 of the bedrooms, the lounge and then the kitchen/diner, they don’t use there radiators now and solely that for heat and the efficiency is great, for every 1KW they use of electric the AC outputs nearly 4KW of heat, which is remarkable !
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Soldato
OK thanks for your response, the house though was built in 2004 as I stated.
There isn't much difference between a 2004 and 2012 build in reality. 2012 should be better but not by much, a 2004 will have insulated floors and walls, double glazing and while it probably had 100m loft insulation when new, topping it up to 350mm isn't exactly a hardship or expensive.
ht
Soldato
For the record, I don't think there's any problem either. They're good engineering. I was just curious what problems you've experienced with them.
55C sounds excessive to me. But I think you've highlight something major which is that consumers don't have a clue how their heating works.
Associate
Ah right! I’ve seen compressors failing, but that was due to manufacturers under charging the system with refrigerant from the factory, they seem to have sorted that though, usual PCB failures the normal stuff
Yer 55degrees is the max it will operate at, but anywhere from 40-50degrees is usually pretty good for radiators, even lower with underfloor heating
Soldato
What sort of dT are you running these systems at?
Soldato
You still may need to make some adjustment to your home in order to use a heat pump as it works differently to a combi boiler.
Some may need new bigger radiators. Some may need new pipe work and a bit more insulation. It depends and people need to be prepared for a much higher electricity bill for obvious reasons.
See how complex a heating system is? Of course there will be some customers that would be clueless as it's a lot to take in order to understand how the whole process works
Soldato
Does the outbuilding need to be heated during the winter to keep they building warm ish or can the hot water cylinder work on very cold room temperatures?
No it doesn’t need to be heated but it’s essential every single mm of pipe is properly lagged.
It will have a slightly higher heat loss but modern cylinders are excellent in that regard so being in an outbuilding will make it slightly less than excellent but still fine.
It’s entirely normal to put them in unheated attached garages for instance.