ASHP – Should do better - Must Do Better

lovesgshp

welda wrote: »

There are plenty courses popping up all around UK to train up for renewable installations, can't speak for all of them but, before being able to apply and train for say GSHP, the trainee will have to have appropriate qualifications ie: BPEC, C&G plumber quals, same for sparks looking to get involved in renewables ie, SELECT registered ect...

However, you will always find the cowboys manage to muscle in to a degree?

:beer:

I looked at one site in the UK which was advertising GSHP's etc, but said it could only offer low prices, as to be certified would push up the cost. Buyer beware is all I can say.

Cardew

Geotherm wrote: »

If the system is sized correctly then there should be no problem. The problem that seems to be in the UK, as it is here, with plumbers, that all these heating experts jump on the bandwagon. Do you check if they are certified installers, or just look at their websites for the blurb!!

I am sorry but you can't ignore the results of the EST trial.

However you just cannot dismiss the EST field trial of 19 ASHPs. This trial was held with the manufacturers involved in the trial. As well as a raft of technical consultants. So that rules out poor installation, incorrect sizing etc wouldn't you think?

If they can't get it right, what chance will there be if a cowboy has installed the wrong system, or the correct system incorrectly.

The results over a year were a huge disappointment! The BBC and EST say investigations are needed.

thechippy who installs systems stated:

Yes I agree.

Some correctly installed and sized systems don't seem to perform either.

Do you think on a year long trial the manufacturers and technical consultants involved would have allowed a bunch of cowboy installers and/or wrong installations to be subject to the report?

They must be horified at the results, knowing the report would get published, and couldn't get it right in 12 months.

Have you read the reports of disasters on here? a £14,000 installation with 2 Ecodans that basically doesn't work and manufacturers and installers cannot get it to work.

That also goes for several new houses with built in ASHPs that don't work.

It really is far to glib to dismiss the loads of poor results as down to the system not being sized correctly.

albyota

OK cardew mine is rubbish I'll rip it out and go back to oil then! Ill rip out the other 60 installations too!

Cardew

Geotherm wrote: »

With your DHW temp @ 58C, I would suggest you turn the thermal disinfection down to a max of 30 mins. At 58C it should not be needed for 2 hrs.

Again this a symptomatic of ASHPs.

Albyota installs ASHP systems for a living, and installed his in a self build house.

You are also in the trade yet have a different view of how to operate. What chance the layman?

We get 'armchair experts' on MSE who read up and diagnose faults and propose solutions.

People should be able to have their house assessed, and buy an ASHP system with cast iron guarantees on heating performance and running costs.

If the house ain't suitable - say so!!

Whilst they have to spend £6,000+ and take pot luck, they should think very carefully on the wisdom of getting such a system.

Cardew

albyota wrote: »

OK cardew mine is rubbish I'll rip it out and go back to oil then! Ill rip out the other 60 installations too!

Why be facetious?

Perhaps I should also be facetious and say all the manufacturers(Including Mitsubishi who manufacture the Ecodan) on the EST trial should have employed you to install their systems, and then they apparently would not have had such dismal results as you seem to be the only person who can get great results!!!

Certainly many people would have been far better off with oil CH(even at the current high prices) that their hugely expensive ASHP systems.

People having spend huge sums of money on anything are usually most reluctant on MSE to admit they are unhappy with their choice.

Yet there are enough just on MSE to admit their systems are a huge disappointment, and what is more the manufacturers and installers have not been able to put it right.

albyota

Geotherm wrote: »

With your DHW temp @ 58C, I would suggest you turn the thermal disinfection down to a max of 30 mins. At 58C it should not be needed for 2 hrs.

There are three reasons I have the immersion set for two hours,

1/ the immersion heater is at the bottom of the tank so I want to heat all of the tank, usually this will be used by wife to have a bath on Saturday night. Or if my son comes home to stay, extra showers.

2/ the standard coil is higher up in the tank so only heats top third of tank, It takes more than 30 minutes to heat the whole 210 Litres of water to 65 degrees from whatever temperature it may be when the timeclock comes on.

3/ I'm a lazy b**ger, and can't be bothered to phaff about with it.

retire_at_50_2

albyota

they are just rough calculations and please feel free to correct

Assuming non heat pump electricity usage of 12kWh a day, 10p a unit, annual bill £440

2008 oil bill is 1450-440 = £1010, assuming 50p per litre ,10kWh a litre and 80% boiler efficiency, ~16000kWh annual space heating and DHW.

2009 assuming non heatpump electricity usage/cost and space/DHW requirement remain the same , heat pump is using 837-440= £397 or ~4000 kWh of electricity which delivers 16000kWh - COP of 4 (more sensible result- should use a calculator more!)

2010 same assumptions - COP of 3.2

If correct these are fantastic results especially with water heating, its performing as well as a GSHP. A year of temperature data here suggested a COP of 2.5 for space heating only.

Your property is well suited to ASHP with decent levels of insulation and UFH, most UK properties aren't like this.

Whats needed are real-life COP figures for ASHPs in typical UK homes so anyone considering changing heating systems under RHI can make an informed decision.


2008, total house fuel bill using oil and electric £1450
2009 total house electric bill £837,
2010 total house electric bill £933, coldest winters!

albyota

OK sorry cardew, I was not trying to be facetious, I have been following all of the threads to do with ASHP's, air to air and air to water since I joined MSE in 2008, I have read all through the, 'over two year old' 2008 EST trial, this is why the MCS was set up? Trained and qualified to know how to size and specify this technology. Late 2009, things were changing with how the systems were spec'd. There needed to be an amount of time, the four seasons, to fully trial the systems.
what seems to be apparent to me is, most of the systems with the horific fuel bills and poor performance are the Nibe exhaust air recovery systems, undersized, Muckybutt with the Heatking, (can only do 55 degrees if its 15 degrees outside) bushyh with the Calorex, say no more, andyWSM with his Trianco, there is a raft of difference when comparing the tech specs / performance data of all these systems with the likes of Mitsubishi, Daikin, Sanyo, I do agree the manufacturers have got to be more honest with their data, and show the performance curves for each model, what can it do, at what temp. defrost cycle, backup elements, etc.

A correctly sized system and correctly sized radiators in a well insulated property will provide all the heating and hot water requirements.
If your on mais gas ......forget it...get a new gas boiler.

albyota

retire_at_50 wrote: »

albyota

they are just rough calculations and please feel free to correct

Assuming non heat pump electricity usage of 12kWh a day, 10p a unit, annual bill £440

2008 oil bill is 1450-440 = £1010, assuming 50p per litre ,10kWh a litre and 80% boiler efficiency, ~16000kWh annual space heating and DHW.

2009 assuming non heatpump electricity usage/cost and space/DHW requirement remain the same , heat pump is using 837-440= £397 or ~4000 kWh of electricity which delivers 16000kWh - COP of 4 (more sensible result- should use a calculator more!)

2010 same assumptions - COP of 3.2

If correct these are fantastic results especially with water heating, its performing as well as a GSHP. A year of temperature data here suggested a COP of 2.5 for space heating only.

Your property is well suited to ASHP with decent levels of insulation and UFH, most UK properties aren't like this.

Whats needed are real-life COP figures for ASHPs in typical UK homes so anyone considering changing heating systems under RHI can make an informed decision.


2008, total house fuel bill using oil and electric £1450
2009 total house electric bill £837,
2010 total house electric bill £933, coldest winters!

Yes, retire at 50, close enough, silly thing is, I know I could get the usage down even more if the hot water cylinder had a 3M2 heat pump coil, and if I could stop the use of three hairdriers every morning (not me). Just a thought that might throw your rough calcs, when I used to have the oil boiler, it was switched off in the summer and the immersion heater was used to heat hot water.

lovesgshp

Cardew wrote: »

Why be facetious?

Perhaps I should also be facetious and say all the manufacturers(Including Mitsubishi who manufacture the Ecodan) on the EST trial should have employed you to install their systems, and then they apparently would not have had such dismal results as you seem to be the only person who can get great results!!!

Certainly many people would have been far better off with oil CH(even at the current high prices) that their hugely expensive ASHP systems.

People having spend huge sums of money on anything are usually most reluctant on MSE to admit they are unhappy with their choice.

Yet there are enough just on MSE to admit their systems are a huge disappointment, and what is more the manufacturers and installers have not been able to put it right.

I think that you have to look at all in perspective. If the system that albyota has installed, plus in many other houses and these are all working well, then you cannot take all ashps as being troublesome. Why only depend on the EST figures, even they say they need longer confirmation. Albyota installs ASHP systems for a living, and installed his in a self build house, then he knows a lot about them as well, but there are always differences of opinion. At least he replied to my question with his reasons.
"You are also in the trade yet have a different view of how to operate. What chance the layman?

We get 'armchair experts' on MSE who read up and diagnose faults and propose solutions. "

Yes I am also in the trade, solely geothermal here, and the suggestions that I make are purely my own opinion, based on many installations over 10 years. There will always be a difference of views with others, but then that is the purpose of the forum. We are members of the IGSHPA, The Association of Energy Engineers and Geoexchange, so hope we know what we are talking about. Also our engineers have to be re-certified every 2 years.
No layman should be advising without giving information in detail of their qualification to quote.