air source heat pump - Viability over oil

blessings3

Anyone eco knowledgeable types tell me if they are a good choice over a new oil boiler ? Very rural so no gas.

muckybutt

You want to be on the Energy forum

Davesnave

You will get better answers elsewhere.

The conclusion I've come to is that air source is only a good option if you can do underfloor heating or have no objection to over-sized radiators that would compensate for the lower water temperatures. Air source is better for steady heat overall, rather than sudden build-up at beginning & end of the day.

Oil is OK if you think you'll sell the place within, say, five years, because at present few will pay more for a property with a biomass pellet boiler, which will cost a lot more, but pay for itself eventually via the Renewable Heat Incentive and likely lower fuel costs. If it's a long term house, I'd look at that, bearing in mind there are cowboys out there, jumping on the bandwagon, just as they did with solar panels. Companies with some track record will likely have been doing commercial installations for around 5 years and be able to prove it.

huckster

Wasn't there a problem with some air source heat pump systems using a lot of electricity ? I can remember a Watchdog programme where a small number of eco homes were built with these and owners were told they would save money on energy. The owners instead found that they had massive electricity bills.

Perhaps this was just a problem with the particular system they had installed.

captainhindsight_2

ASHPs are good, but like someone said above you will need under floor heating, large radiators or fan assisted radiators this is because they operate at a lower temperature than traditional heating.

A lot of the criticism about ASHPs are about the installation and not the technology,

The technology is good, and will work in any property but it needs to be designed correctly for your building.

An easier/safer option would be biomass, guessing you already have an oil tank outside this can just be replaced with a hopper for wood pellets or wood chips then a biomass boiler inside.

This can be a straight swap from the oil boiler, because the hot water flow is high temperature. You will not need to change radiators etc,

Both these technologies will qualify for rhi, biomass will be more expensive but the roi will be quicker with biomass.

and if space is limited there are some great small biomass boilers, if you check out the MCZ boilers, there are small and are attractive enough to have in your living room

anotherbaldrick

The trouble with Air Source heat pumps is that you get the compressor working it's b'llocks off when the temperature goes sub-zero, just when you are looking for the units max output.

Furts

And whilst it does not answer OP's post there is no substitute for meticulous insulation on a home. For an average home it will then be found that heating is almost redundant and a boiler is required mostly for hot water. If a solar pv, and/or a solar thermal system is added then the boiler becomes even more redundant.

Indeed, many people could live effectively with a solar system and no boiler, should they wish to do so. An electric supply would be needed, ideally on Economy 7 or 10, but gas, oil, and biomass and boilers would be items for other consumers to worry about.

anotherbaldrick

Furts wrote: »

And whilst it does not answer OP's post there is no substitute for meticulous insulation on a home. For an average home it will then be found that heating is almost redundant and a boiler is required mostly for hot water. If a solar pv, and/or a solar thermal system is added then the boiler becomes even more redundant.

Indeed, many people could live effectively with a solar system and no boiler, should they wish to do so. An electric supply would be needed, ideally on Economy 7 or 10, but gas, oil, and biomass and boilers would be items for other consumers to worry about.

If you do that you will not be having windows with trickle ventilation and will therefore have to install an in/out fan ventilation system with heat reclaim or the house will soon smell like a sumo wrestlers jock strap

huckster

anotherbaldrick wrote: »

If you do that you will not be having windows with trickle ventilation and will therefore have to install an in/out fan ventilation system with heat reclaim or the house will soon smell like a sumo wrestlers jock strap

I have always wondered about that. If you insulate a house so well that it is not often necessary to have heating on, what do you do about moisture in the house ? You have got to have ventilation, so there will be some cold air to deal with. Unless it is sunny, it is going to take time for the house to get back to a reasonable temperature.

Martyn1981

huckster wrote: »

I have always wondered about that. If you insulate a house so well that it is not often necessary to have heating on, what do you do about moisture in the house ? You have got to have ventilation, so there will be some cold air to deal with. Unless it is sunny, it is going to take time for the house to get back to a reasonable temperature.

Super insulated houses have MVHR (mechanical ventilation and heat recovery) this device has a series of heat exchangers in it and is extremely efficient, up to 90%.

As the stale air is vented out, the majority of the heat is removed, and used to warm up the replacement air coming in. Probably consume less than 1kWh per day.

The key point though is high insulation and minimal heating needs to start with.

Mart.

dotdash79

My Cousin has an heat exchange in his house in Ireland, It uses a lot more energy than he was told when he bought it.