ASHP or MAINS GAS?

[Steve Williams]

Hi and thanks for reading my query

I am renovating an terraced Edwardian house which will be well insulated. The gas boiler is old and the entire Central Heating system is a mix of ugly rads, normal piping and microbore, in short it needs replacing.
I will be fitting UFH regardless of the ASHP/Gas question as I prefer it and the floor boards need lifting and insulation installed anyway.
We have a mains gas supply.
Is an Air Source Heat Pump a better choice than gas?

Steve

 

[tamz]

More expensive to run than mains gas

 

[Howsie]

Sad but true.

 

[Roger Welton]

Mains gas, cheaper to run, cheaper appliance cost. Win win

 

[Steve Williams]

Thanks guys, 3-0 then! Does the Renewable Heat Incentive/Green Deal and rising gas prices make any difference to the view its better to stick with gas?

 

[TBServices]

It's a sham, you'll probably never see any reward from it like many people who have fitted solar pv

 

[michael c]

have a look on here steve there are a few people complaining the ashp isnt sufficient at certain times of the year

 

[eaton]

I can run ashp cheaper than gas, I know this as I've done it, install cost is quite a bit more yes but with grants rhi etc will be well worth it, I'm travelling to gloucestor soon to do just this. House banked with pv too

 

[CES]

At the moment mains gas is cheaper but that will change in the years to come. ASHP's if installed correctly work very well, more efficiently than any boiler.
If they didn't work why would Worcester, Glowworm, Vaillant etc all have their own versions?
You have to be able to distinguish between fact and fiction, speak to people who fit them, ask to see one working, verify with the occupiers that everything is ok.
I'm not sure if the RHI will be available for houses connected to the gas network, lots of mixed messages out there so I wouldn't bank on that to offset any costs. The installation cost is greater but in the longer term it has its benefits, no need for flueing, no CO risk, servicing is minimal etc.

 

[Ray Stafford]

The trouble is, there are so many variables. Its impossible to give a certain answer.

What will the cost of gas be in years to come?
What will the cost of electricity be in the years to come?
Is the system design right for optimising ASHP in this specific property?
What will government policy be on RHI next year, in 5 years time and in 10 years time?
How long will you live in the property?
What other energy efficiency measures could you have taken with this investment?

You only have to move each assumption by a relatively small amount, and you can "prove" whatever you like.

 

[eaton]

Heard a rumour people on gas will get rhi but at reduced rate

 

[tamz]

I'm going back to an open fire and buying a chainsaw :smile:

 

[hammers4spanner]

i keep hearing ashp can be quite noisey

 

[eaton]

I've done a couple of vids here's one

Samsung heat pump - YouTube

 

[Howsie]

They can be quite noisy, of that there is no doubt. They should be place out of the way if at all possible.

 

[eaton]

Who's are noisy? I've fitted a few now and best so far are Samsung followed by hitachi

 

[Howsie]

They all are if the customers expectations aren't set right. The move a lot of air and this constant'ish noise can be intrusive.

 

[radswilldo]

I can run ashp cheaper than gas, I know this as I've done it, install cost is quite a bit more yes but with grants rhi etc will be well worth it, I'm travelling to gloucestor soon to do just this. House banked with pv too

With out being rude Eaton, can you tell me how? I have spoken to Grant, Nu-heat, Vaillant, Worcester etc and none of them advise taking anyone off grid, in fact they are against it. NO manufacturer and no mathematics back up your statement. I did log on to start a thread about who is a actually taking customers of the grid for ASHP, as since Christmas I have had four phone calls from customers regarding this. ASHP is not going to touch a low modulating condensing boiler with modulating control. Do any manufacturers post on here?

 

[eaton]

I've specced one against ng and for a 4 bed house. It will run at roughly £60 less than ng.

 

[eaton]

I'd still not advise it though without rhi confirmation as install is likely to be treble and payback time will be quite long

 

[Reg Man]

On a personal view point. I have Daikin Altherma ASHP in an older not brilliantly insulated house and in comparison to my old house which was smaller and very well insultated, up to current insulation standards with mains gas condensing boiler, my fuel bills are cheaper now with the ASHP and all electric. I run the electric on an economy 18, so cheaper night tariff but also cheaper daytime tariff for the ASHP. I am considering putting 16 PV panels on the roof.

I agree that they are noisier, but not any different to an air con unit. So wont be great for everyone. My ASHP is fine as I do not have any nieghbouring houses close by and I can't even hear it when indoors.

 

[eaton]

That's great to hear. Issue with tarriffs is I think a lot of the energy companies are becoming aware. I'd heard economy 10 was the best for heat pumps but not many offer it. Ill have to look at 18 as I'd not heard of that

 

[Reg Man]

I am nt sure if economy 18 is available anymore. I managed to get it, but don't think the suppliers are to keen to give it out. Probably because the day time stored heat for the ASHP cheap rate which is only 1p per kW/hr than the night time rate.

 

[eaton]

You saying you get daytime rate at 1pkw? If so that's amazing

 

[Reg Man]

You saying you get daytime rate at 1pkw? If so that's amazing

No! 1p more than the night time rate. Night time rate 6p day time stored rate 7p.

 

[eaton]

Ah right, that's still a very good deal, I'd hold onto that forever!!

 

[Silent Dancer]

From the Energy Saving Trust website.

What fuel will you be replacing? The system will pay for itself much more quickly if it's replacing an electricity or coal heating system. Heat pumps may not be the best option for homes using mains gas.

 

[markfxy]

They all are if the customers expectations aren't set right. The move a lot of air and this constant'ish noise can be intrusive.

are you trying to tell me that gas boilers are totally silent if so why does my old worcester combi wake me up at night when the pump kicks in for no reason, at least with a heat pump they are outside and the noise is barely audible even when standing next to them

 

[Roger Welton]

I am constantly surprised how quiet some of the new gas boilers are, the ideals and remehas in particular

 

[Reg Man]

Sorry could'nt hear that my ASHP just kicked in:wink_smile:

 

[Howsie]

are you trying to tell me that gas boilers are totally silent if so why does my old worcester combi wake me up at night when the pump kicks in for no reason, at least with a heat pump they are outside and the noise is barely audible even when standing next to them

Clearly I'm not.

 

[TBServices]

I am constantly surprised how quiet some of the new gas boilers are, the ideals and remehas in particular

The ideal vogue is amazingly quiet - practically silent.

 

[Howsie]

are you trying to tell me that gas boilers are totally silent if so why does my old worcester combi wake me up at night when the pump kicks in for no reason, at least with a heat pump they are outside and the noise is barely audible even when standing next to them

Btw, old says it all. Maybe time for a change to a ASHP?

 

[Centralheatking]

I am not going to read below because a really switched on associate of mine
who has vaste experience in the HVAC industry installed a ASHP in his sons house
really just to see ..........and he said to me last Sat that it was rubbish and a total
waste of time and money- his men would not have installed it incorrectly

Hi and thanks for reading my query

I am renovating an terraced Edwardian house which will be well insulated. The gas boiler is old and the entire Central Heating system is a mix of ugly rads, normal piping and microbore, in short it needs replacing.
I will be fitting UFH regardless of the ASHP/Gas question as I prefer it and the floor boards need lifting and insulation installed anyway.
We have a mains gas supply.
Is an Air Source Heat Pump a better choice than gas?

Steve

 

[eaton]

Heat pumps will work in ANY environment but must be sized correctly.

 

[Gerard17]

Heat pumps are only any good in new builds and we're gas is not available at the moment gas all the way. In a retro the insulation has to be to the maximum but it still wouldn't be worth it. A little air source heat pump is good for a conservatory as it can blow hot in the winer and cold i the summer

 

[markfxy]

I am not going to read below because a really switched on associate of mine
who has vaste experience in the HVAC industry installed a ASHP in his sons house
really just to see ..........and he said to me last Sat that it was rubbish and a total
waste of time and money- his men would not have installed it incorrectly

obviously it hasn't been installed correctly, they're probably just a bunch of pipe stranglers who haven't got a clue

 

[Reg Man]

I am not going to read below because a really switched on associate of mine
who has vaste experience in the HVAC industry installed a ASHP in his sons house
really just to see ..........and he said to me last Sat that it was rubbish and a total
waste of time and money- his men would not have installed it incorrectly

If there so rubbish, why does my ASHP work so well and efficient, along with 1,000's of others? Your associate must have missed something along the way, a really expensive "just to see".

 

[Centralheatking]

Fair play to all - perhaps my opinion because of my friends experience is premature.

We will get the system rated and compared and report back on this forum in due
course.

Thanks 4 all your input

 

[eaton]

Heat pumps are only any good in new builds and we're gas is not available at the moment gas all the way. In a retro the insulation has to be to the maximum but it still wouldn't be worth it. A little air source heat pump is good for a conservatory as it can blow hot in the winer and cold i the summer

You are extremely misguided. I suggest you fit a few in very differing situations before making comments that make you look more than silly.

 

[gassafe]

Rip off Britain was on last night on bbc 1!

It featured a whole new build housing estate with NIBE heat pumps that were supposed to be cheap to run! Long story short, they were costing a massive amount to run in electric usage!!! The tenants could not afford to turn them on!

They were all ripped out & gas boilers fitted! Everyone's happy again...

BBC News - 'Efficient' heating system left families with big bills

There was a lot of complaints up & down the country about these systems... I don't think they live up to there claims!

On another perspective, in years to come who is going to maintain these things? They will defs be a lot more to repair than your average gas boiler! How much to replace a compressor on those big outside noisy units?

 

[CES]

Rip off Britain was on last night on bbc 1!

It featured a whole new build housing estate with NIBE heat pumps that were supposed to be cheap to run! Long story short, they were costing a massive amount to run in electric usage!!! The tenants could not afford to turn them on!

They were all ripped out & gas boilers fitted! Everyone's happy again...

BBC News - 'Efficient' heating system left families with big bills

There was a lot of complaints up & down the country about these systems... I don't think they live up to there claims!

On another perspective, in years to come who is going to maintain these things? They will defs be a lot more to repair than your average gas boiler! How much to replace a compressor on those big outside noisy units?

This program was on last year, they were incorrectly specified by the house builder and incorrectly operated by the householder.
Its different from a Gas boiler as anyone with half a brain can fire in an oversized boiler and it doesn't affect the energy bills as much.
You need to be trained in the installation, design and limits of operation of Heat Pumps.
The technology has been around for years within the air conditioning industry so to try and say this technology doesn't work just isn't the case. What does need to happen is that installers, householders and the general public need educated on this technology, instead of being fed gossip and horror stories of badly designed and installed cases.

 

[Si H]

I have a Nibe fighter 11 kw ASHP in a 160 sq metre house with overlay ufch throughout, also 1.75 kw peak pv system. Last quarter bill for electric for heat, cooking, lighting, tv etc etc £300.
It is comparable with gas in running costs if not cheaper. I have also blocked the immersion to let the heat pump run flat out.
All in all works very well with minimal maintenance

 

[Reg Man]

QUOTE>On another perspective, in years to come who is going to maintain these things? They will defs be a lot more to repair than your average gas boiler! How much to replace a compressor on those big outside noisy units?

Yes you are absolutely correct. The compressors are very expensive, but they are extremely reliable and will most likley last longer than a gas boiler. I don't know where all this noise issue comes from. Ok. If you have mains gas and live in a built up area, then a gas boiler is probably a sensible option. When there is no mains gas and don't have to squeeze the unit in somewhere inapropriate the ASHP is a good sound solution. They must be used differently to a gas boiler, but the benefits are very good. Its all about understanding the limitations and how they work.

 

[eaton]

Issue with nibe is house builders just built in 6kw immersion heaters as heating cost, then it kicks in costing huge amounts

 

[Jimbob]

At the moment, I would stick with mains gas. ASHPs don't really financially add up when compared to natural gas at the moment

 

[markfxy]

I'd go with gas and when your boilers kn-ackered in 5 years time go for an ashp they'll be even more efficient then

 

[Pipes Plumbing]

If you're on mains gas it'd be mains gas for me over an ASHP sadly, for the following:

1- More costly per kW/h output compared to mains gas.
2- Even at 3.5 COP the CO2 out per kW/h is hight from ans ASHP at the moment due to power production being so dirty and transmission losses so high (up to 90% in some remote areas!!)
3- More expensive upfront for the ASHP compared to a gas boiler.
4- With the new standardised energy tariffs on there way in, unless the gas supply is totally disconnected, you will be liable for a standing charge anyway, even if it is used for cooking only...

Just my take on it... I struggle to make them stack up when anyone's on mains gas at the minute (and I'm a biomass engineer so favour renewables!)

 

[eaton]

Got one to do, I'm looking at hybrid it, so hw is off gas boiled and all heating on heat pump, then if ever needed gas can kick in. Works well, will be very good as he has 4kw pv, lad I met at Samsung other week said his 4kw pv pretty much powered his 9kw ashp for whole of April which is impressive

 

[eaton]

Ill add I've got a 16kw Samsung at my house now, 1975 4 bed detached all rads, ive specced rads for 45c as it works out £90 a year better than 50c so was worth tiny outlay. Double glazed and insulated 20 years ago, loft too. I'm actually logging it with Samsung as a trial unit. I've got a separate elec meter that is reading everything on heating side ie ashp, immersion, controls, pumps the lot. I'm saving daily data and its looking great against the oil I had when I moved in 2 months ago, I'm posting most of results on twitter page @kfiskplumbing and Facebook page Kfiskplumbingandheating.com so if interested take a look. At least I can give actual real time results. Cost to heat my house yesterday inc hw was 69p, day before 78p