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

 

[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

 

[Jimbob]

Have you got a heat meter to see what you're actually producing?

Definitely starts adding up when comparing to oil I must admit.

 

[eaton]

No don't see need for it, end of day you just want to know run cost. I can work out cop at any time using a calc

 

[Jimbob]

Worth looking at though, we've got a Panasonic setup with meters and heat meters, give a better indication of how efficient it is rather than just averaging with a COP factor. And it could be that you may require a heat meter to get any future RHI payments

 

[eaton]

I offered mcs to send me one they said no! Said ok sod you then

 

[peteheat]

My advice to the OP is insulate very well forget todays regulations and double up if possible, draught proofing, good quality windows screen doors etc.

Top quality heating controls especially for UFH, preferably a thermostat in every room back to a manifold as your heating control centre.

Now you have a foundation for the future, today you fit a quality gas boiler, however you leave the pipes in place to fit your heat pump to so the installation cost is not crazy.

From my experience the majority of failures with heat pumps are caused by salesmen who don't understand their product or construction in general so they sold them as a "one solution suits all".

The new way of thinking should be future proofing our homes, from what I can see there is no free heating system coming along in the near future and our traditional fuels (even wood) are getting more expensive be it gamblers on the stock exchanges, political turmoil or the fact that as gas and oil get more expensive homeowners just won't be able to afford them.

 

[Howsie]

An air-source heat pump is a good choice. Yes it is a more expensive little bit but well worth.

Cricket and rice?

 

[Steve Williams]

Thanks to everyone who responded! We opted for a gas boiler with a solar thermal. UFH downstairs, rads upstairs. Very effective.

 

[Phil_Plumb]

excellent choice, the solar thermal will heat up the water in the cylinder by x amount of degrees C that the required energy from the boiler will be less to heat up the cylinder to the correct temp.

Saving gas and saving energy using a tried and trusted tech!

That being said, if gas keeps going the way it is, my boiler will be coming out and all 3 out of 4 fireplaces will be opened up (frontroom already done) i will put in a back boiler with pump to an indirect cylinder to provide my HW via a 3 port valve for the rads.

have a plentiful supply of free logs anyway!

 

[Steve Williams]

Oh and a woodburner in the front lounge and a rainwater harvester for toilets and washing machine to up our Eco-credentials, the water tank only went in in May do is now nearly empty, doh!

 

[Dickie]

Not having read all the posts, but a good few. None of you so called ASHP experts have mentioned the COP of these units!! Also, if you had any small insight as to how refrigeration actually works you'd know that volume circulation is required for the optimum output & efficiency, so LLHs are not worth fitting, a buffer tank is always required.

A ASHP would never be as cheap to run as a modulating Nat Gas condensing boiler. OP don't listen to the ex-used car salesmen, it's all mince they talk.