ASHP or GSHP or Solar panel

albyota

TiredGeek wrote: »

But you are in Italy, with respect, we don't grow olives and lemons in the Uk for a reason - it's too bloody cold!
You might have winters as cold as we do but your summer is substantialy warmer which both reduces the number of months you need heating and it warms the fabric of the building so you need a bit less from that also.

You use about £1000 a year for everything, mine use about £10 a day just for the ASHP, so I'll use that much in just 100 days the way they're working (or not) at present. I would guess you get good weather from mid March to early November, in northern Scotland I get it from late April to early September, so I have more winter to deal with (if you can call northern Scotlands weather "good" at any time)

Maybe the answer isn't ditching the ASHP for something else, it's getting out of this screwed up country and retiring somewhere warm

TiredGeek, you know why your system is costing a lot, the monkeys who installed it have it plumbed it up incorrectly, i have followed your case on this forum and the refrigeration engineer forum,

after advise from an engineer who really knows his stuff.... wrote

25-01-2011, 03:03 PM
If there is not enough flow there is not enough energy in the water circuit and the heat pumps will stop defrosting to prevent the water in the plate heat exchanger from freezing and cracking it, this would be the only reason they would partially defrost and stop which can be seen in one of your pictures where the top of the coil is defrosted but the bottom is not. Once you get a ON/Off demand from the stat or clock this cycle will start again. At the end of a defrost the fan spins at full speed which blows the moisture away to prevent "bridging" I've witnessed this hundreds of times and it works, so much steam comes out of the front of the units some customers have called thinking they're on fire.


and you wrote.....

"This makes so much sense I really can't understand why the install company (who are not a small unknown firm) and Mitsubishi's own technicians haven't figured it out ! I have witnessed the first bit where it tries to defrost and gives up, I have passed all the codes the units flashed up when this happened on to both Mitsi tech and the installers, they didn't figure it out.
I agree with the amount of water vapour that blows out, it's like fog when both of them do it. I must say I have worries about this building up on the vent covers in below freezing ambients, but until it's working properly we won't know

"I'm now tending to believe that if you say these things will work at the house, if we get them plumbed in correctly, then they will
I sure hope it's just a simple replumb job and we're good"

it appears to me that unluckily you had a bad installation team who have plumbed it up all wrong, and an incompetent Mitsi engineer who didn't know what flow rate to set it at.......the flow rate should be at least 40.1 Litres per Minute, why were they set at 25 l/min?.

TiredGeek

albyota, this is all true
I was just pointing out that comparing apples to oranges, or even lemons, isn't a good idea....
I'm not trying to knock Geotherm, it's just that the amount of electric he uses in Italy isn't going to relate to the amount we are likely to use in the UK.

Mine are coming out this year. Gonna sue 'em for a refund if it comes to it, we have nothing to lose as the system is simply too costly to run, so spending another couple of grand on solicitors is cost effective
Don't know what is gonna go in yet, probably LPG 'cos it's not as easily knicked out of the tank as oil.

Cardew

albyota wrote: »

TiredGeek, you know why your system is costing a lot, the monkeys who installed it have it plumbed it up incorrectly,

it appears to me that unluckily you had a bad installation team who have plumbed it up all wrong, and an incompetent Mitsi engineer who didn't know what flow rate to set it at.

This is surely the indictment of the ASHP ‘industry’.

This post sums it up!

I wrote before that I had some sympathy with Cardew's original post.

Now, after a lot of research, and having dealt with several potential installers for an ASHP at my house, I've even more sympathy!

The level of professionalism shown by potential installers has been awful. No shows, outright lies, nil response to queries, ludicrous heat requirement estimates, no response to contacts - only once did a company write to apologise that they were too busy. Its maybe a miracle that I've just had a second quote, not on the basis discussed with the surveyor though (the only one who actually made it to the house), and weeks late.

While I'm convinced that the market will mature I feel that what expertise is out there, is spread so thin that its pot luck if you get a knowledgeable installer.

So although I still consider ASHPs to be a viable retrofit option for those off gas grid, it seems the chance of getting a badly designed system that will not deliver on promises may be all too real.

lovesgshp

TiredGeek wrote: »

But you are in Italy, with respect, we don't grow olives and lemons in the Uk for a reason - it's too bloody cold!
You might have winters as cold as we do but your summer is substantialy warmer which both reduces the number of months you need heating and it warms the fabric of the building so you need a bit less from that also.

You use about £1000 a year for everything, mine use about £10 a day just for the ASHP, so I'll use that much in just 100 days the way they're working (or not) at present. I would guess you get good weather from mid March to early November, in northern Scotland I get it from late April to early September, so I have more winter to deal with (if you can call northern Scotlands weather "good" at any time)

Maybe the answer isn't ditching the ASHP for something else, it's getting out of this screwed up country and retiring somewhere warm

Thanks Tiredgeek.
I appreciate you live a lot further north so it is far more difficult to make a comparison, plus mine is a GSHP. Normally on a Monday morning, I check external temps and log them, plus pump running times. Temps taken between 9.00 and 10.00 a.m.
Our lowest temp in Sept - March on the data I have is as follows for 2010/2011:
Sept 15.8C
Oct 7.5C
Nov 6.2C
Dec 0.4C
Jan -1.3C
Feb 4.4C
Mar 5.0C

Just as a additional point, we have had 23C here today, but tomorrow we are going to be a lot cooler!!
http://www.ilmeteo.it/meteo/Amandola

lovesgshp

Tiredgeek.
But you are in Italy, with respect, we don't grow olives and lemons in the Uk for a reason - it's too bloody cold!
I have not seen oranges or lemons grown in this area, as we are too close to the mountains. Most are grown much further south, where it is far warmer.
You might have winters as cold as we do but your summer is substantialy warmer which both reduces the number of months you need heating and it warms the fabric of the building so you need a bit less from that also.
A stone built house, with no insulation looses heat far quicker than a brick built unit through the walls.
If you think we are always much warmer, it may be worth having a look at the attached article for a installation in the north of Italy where ground loop input temps got to -8C.

http://pangea.stanford.edu/ERE/pdf/IGAstandard/SGW/2008/maritan.pdf

i8change

Anyone on the Gas main who is thinking of getting an ASHP should watch "Don't Get Done Get Dom - Eco Heat Pumps episode" on the BBC iPlayer now.

http://www.bbc.co.uk/iplayer/episode/b010vzmv/Dont_Get_Done_Get_Dom_Series_5_Eco_Heat_Pumps/

Basically if you are on the Gas main you should not fit one to save money. See Energy Saving Trust comments at 22 Mins 37 Secs into the program plus ASA ban on Danfoss advert at 35 Mins.

Cardew

i8change wrote: »

Anyone on the Gas main who is thinking of getting an ASHP should watch "Don't Get Done Get Dom - Eco Heat Pumps episode" on the BBC iPlayer now.

http://www.bbc.co.uk/iplayer/episode/b010vzmv/Dont_Get_Done_Get_Dom_Series_5_Eco_Heat_Pumps/

Basically if you are on the Gas main you should not fit one to save money. See Energy Saving Trust comments at 22 Mins 37 Secs into the program plus ASA ban on Danfoss advert at 35 Mins.

https://forums.moneysavingexpert.com/discussion/2968958

Just as well the guy in the that programme switched back to gas before the(very cold) last winter.

A further point about ASHPs that is rarely considered, is the economics of spending £11,000 on an ASHP system.

£11,000 invested in a long term bank account will produce £440pa @ 4% interest(compounded). So that means that you need to save that sum(£440) in heating bills before you start considering any savings on your normal heating bills.

lovesgshp

Agree Cardew.
Even with the GSHP detail I linked to above, the savings were only estimated at 1.00 Euro per day to mains gas here. ASHP obviously lower. I have a client here who retrofitted a GSHP from LPG and has so far saved around 3000.00 Euro per year on GPL fuel costs. He also has the advantage of income tax reductions of up to 55% (over 5 years through income tax) of his total expenditure for the system (23K) (includes excavations, plumber costs etc, plus extras to meet the minimum saving of 20% of his energy bill. His break even point should be about 4 years. Plus this year there is a very low electricity tariff introduced specifically for heat pump use. Both above include Air/air, water/air water/water. UK should get its act together and offer better incentives, but only on fully certified installations as we have here.
I think our incentives are a lot better than you have in the UK.

Only existing buildings can benefit of 55% tax deduction, no benefit for new buildings/houses. Buildings have therefore to be registered by local "Catasto". This benefit is granted for all works inproving thermal and energetic consumption of the house, the complete list of works is available on Enea website, www.enea.it.
Amount granted are:
-euro 100.000 for lowering energetic need of the building (new heating or conditioning system) (that is 55% of Euro 181.818,18);
-euro 60.000 for house insultion, windows including shutters, roof, etc (that is 55% of Euro 109.090,90);
-euro 60.000 for solar panels (that is 55% of Euro 109.090,90);
-euro 30.000 for winter climatisation systems (that is 55% of Euro 54.545,45).

When all works are finished, a qualified engineer has certify that all works are complying with requirements, and can fill in Form E of "Decreto del Ministro dell'Economia e delle Finanze del 19/02/2007" and sent it to Enea by internet.