Air Source Heat Pumps

Cardew

The Google translator has defeated me as well.

lovesgshp

Cardew wrote: »

The Google translator has defeated me as well.

Can copy it in Italian if you prefer that .
Basically, it compares the cost of a new LPG system install against a GSHP unit, both of 7KW output, for a new installation.
It then increases the energy costs from historic data, to give the saving potential against the initial investment. As I cannot post the graph it is more difficult to explain, plus the pricing is based on costs here, so may not be fully relevant to the UK.
The calculations are based on a GSHP cost of Euro 14080, against a LPG installation cost of Euro 9350. The heat pump contains the circulating pumps, 3 way valves and DHW tank, which are not normally included in a normal gas boiler installation, so this is why the difference is not so high. Also, we only costed for a enamelled steel cylinder, as the units we use are double shelled stainless steel, which would push the DHW boiler cost for the LPG unit much higher.
Year 1 was calculated @ 913Euro for the GSHP against 2392 Euro for LPG.
Year 2 @ 922 v 2487
Year 3 @ 931 v 2587
Year 4 @ 941 v 2690

These were calculations from 2007 and I know that energy prices have risen since then, but in the example the break even point was actually 3 years, although we normally quote 4.
We do have a English client, who is saving around Euro 2500 per year on his GPL costs after a retrofit and he says his heating temperatures are more stable than with LPG.
HTH

Cardew

Really not much point in spending a long time discussing Italian heating systems - albeit I did ask. However it does rather seem like it is a report by Heat pump companies for potential heat pump customers!

An LPG system with a 7kW output??

How many kWh did the 923Euros purchase? and how many kWh did the GSHP output?

At the present rates you quoted(33 cents/kWh) 923 Euros would purchase 2,800kWh. A COP of 3.0 means 8,400kWh output.

The googled Italian report prices LPG at 9 cents/kWh(65cents/litre). It now costs 10.2 cents/kWh.

So 2392Euros would purchase at today's rates(10.2cents/kWh) 23,450kWh with a 90% boiler efficiency that is 21,100kWh.

So for the GSHP to supply 21,100kWh at a COP of 3.0 would need 7,030kWh input at a cost of 2321 Euros.

So it seems to me that the cost of running a GSHP and LPG are roughly the same.

Using mains gas the cost of that 21,100 output from the boiler(at 90% efficiency) would cost 1860 Euros.

It also seems strange that in Italy you use a figure of 14,500Euros for a GSHP installation, which is way below the price on a GSHP system in UK where I have never even heard of any system under £20k. Yet your 9,350Euros for an LPG installation is double the cost of a similar system in UK.

Perhaps you should install GSHPs in UK and get a UK firm to install LPG systems in Italy;)

lovesgshp

Cardew wrote: »

Really not much point in spending a long time discussing Italian heating systems - albeit I did ask. However it does rather seem like it is a report by Heat pump companies for potential heat pump customers!
Please think what you want, but even retrofit customers here are very happy with the savings of thousands a year over LPG.

An LPG system with a 7kW output??
This was a comparison to 2 equivalent output systems, which was researched as a comparison. 7 kw would be equal to circa 90 sq mtr property with good insulation.

How many kWh did the 923Euros purchase? and how many kWh did the GSHP output?
If you had read the initial detail, it said 7000kwh output and the LPG unit the same.

At the present rates you quoted(33 cents/kWh) 923 Euros would purchase 2,800kWh. A COP of 3.0 means 8,400kWh output.
Apologies, the initial basis was on a lower average rate cost, albeit we have a new rate here for heat pumps @ 18 cents kwh on a seperate meter, which is a good saving, as it is not incremental. I did say the maximum was 33 cents per kwh, but that is based on a daily usage charge, which without going into great detail is on a scale, incremented in stages from the lower rate to the higher on 4 levels. In the UK as I understand , your electricity gets cheaper the more you use, here it gets higher.

The googled Italian report prices LPG at 9 cents/kWh(65cents/litre). It now costs 10.2 cents/kWh.
Here it changes by the day, as does electricity by the month. Remember the electricity companies here are as bad as yours in increasing prices.

So 2392Euros would purchase at today's rates(10.2cents/kWh) 23,450kWh with a 90% boiler efficiency that is 21,100kWh.

So for the GSHP to supply 21,100kWh at a COP of 3.0 would need 7,030kWh input at a cost of 2321 Euros.

So it seems to me that the cost of running a GSHP and LPG are roughly the same.
Think you lost the plot of the whole scenerio completely. Both examples were based on a 7000KWH heating output, by the 2 units, not 21000kwh.

Using mains gas the cost of that 21,100 output from the boiler(at 90% efficiency) would cost 1860 Euros.

It also seems strange that in Italy you use a figure of 14,500Euros for a GSHP installation, which is way below the price on a GSHP system in UK where I have never even heard of any system under £20k. Yet your 9,350Euros for an LPG installation is double the cost of a similar system in UK.
14.5k is normal for a 7kw system here and circa 18k for a 14kw unit. In your currency, this would work out at about 12k to 15k @ todays exchange rates. The comparison is what is charged here for a system. I cannot comment if you get ripped off in the UK with the pricing.


Perhaps you should install GSHPs in UK and get a UK firm to install LPG systems in Italy;)

Maybe we should, but the example was just to show how the difference in cost is not that massive, when you add all the extras into the equation.
I appreciate your posts Cardew, but I hope that you can understand that we do not sell geothermal systems in the Uk and am only trying to help on this site, just as you are with your posts.

Cardew

lovesgshp wrote: »

Maybe we should, but the example was just to show how the difference in cost is not that massive, when you add all the extras into the equation.
I appreciate your posts Cardew, but I hope that you can understand that we do not sell geothermal systems in the Uk and am only trying to help on this site, just as you are with your posts.

Thanks, and I wasn't being critical of yourself, your knowledge and assistance on heat pumps is much appreciated and far in excess of the little I know about the devices.

However I was just taking issue with the report as it didn't, and doesn't, make sense to me.

Year 1 was calculated @ 913Euro for the GSHP against 2392 Euro for LPG.
Year
2 @ 922 v 2487
Year 3 @ 931 v 2587
Year 4 @ 941 v 2690

These were calculations from 2007 and I know that energy prices have risen since then

Think you lost the plot of the whole scenerio completely. Both examples were based on a 7000KWH heating output, by the 2 units, not 21000kwh.

I have never heard of a 7kW gas boiler.

Do people fit a GSHP when they only want it to produce 7,000kWh pa? people can use close to that for Domestic Hot Water.

Also for a similar new property using LPG and only wanting 7,000kWh why would they not use a combi and do away with the expense of a DHW tank?

Anyway my issue is with the report!

If the GSHP was only required to produce 7,000kWh with a COP of 3.0 that would require an input of 2,333kWh. Yet according to your interpretation of the report in 2007(year 1) the cost of electricity for the GSHP was 913 Euros. That would mean the 2,333kWh was then costing over 39cents/kWh. - clearly it wasn't

For a 90% efficient LPG boiler to produce 7,000kWh it would require 7780kWh input - so 1,051 litres. According to the Italian report the price(then) of LPG was 65 cents a litre('Cost LPG 0.65 Euro / l') so that would cost 683 Euros.

Yet your interpretation of the report states the cost of LPG was not 683 euros but 2,392 Euros. As the price of LPG is clearly stated as 65 cents a litre that sum would buy 3,680 litres instead of 1,051litres. That 3680 litres is 27,232kWh

Something ain't right with the report!

If you can now get electricity @ 18 cents/kWh with a COP of 3.0 it will cost 420 Euros to produce 7,000kWh.

LPG will cost 793 Euros (7780kWh x 90% x 10.2cents/kWh)

So a saving of 373 Euros pa will take many years(not 4 years) to break even. Using your 14,500 Euros for a GSHP and 9,350 Euros for LPG(a figure I find hard to believe - is it not the Italians being ripped off;)) it will take 14 years to break even.

With Mains Gas which wouldn't require a fuel Tank it would be over 40 years.

[Deleted User]

jeepjunkie wrote: »

Since the start of the heating season it slowly dawned on me that something with the ASHP was not right...

It seemed to come ok but later in the evening it would go off and had to be manually prompted into life... Oh great just when we start to get frost :mad:

The troubleshooting begins...

Check for error codes, none.
Check all pumps are working.
Check the flow rate .
Check clocks were all synched on the wireless thermostats - they were not but after thinking it helped it did not.
Several wireless devices have been added to the house and suspected interference with the wireless thermostat.
Reboot the whole heating system, nope.
Check the wireless thermostat was linked to the base unit.
Could it be an issue with the solar immersion? But is not connected to the ASHP in any way???
A brief powercut happened around the same time, could it have caused an issue???

Ahhh... Perhaps the wireless thermostat needed new AA batteries being a few years old. Yup problem sorted, DOH!

The wireless thermostat can change the temp multiple times a day and what I think was happening by the late mid evening a temp change was scheduled it did not have enough battery to transmit over and above the other six wireless devices [current cost x2, broadband, cordless base, vodafone & EE repeaters all in the loft space but not together]. So guessing the batteries would have recovered enough to start the system in the morning...

I'm not totally finished with ruling out the mobile phone repeaters so these are still unplugged.

Well there you go that's my idiots guide and I feel like one

UPDATE

The system pressure was also too low so all perfect now

In the process of troubleshooting I removed the solar immersion :doh:

With the wintery conditions and the heat pump running regularly little point in reconnecting for a few months. Thinking about changing it for something else like the optimmersion...?

Cheers

helpjack

Hi everyone, Long time reader, first time poster on the thread! I have recently bought a house in a village without mains gas so looking for advice. The house needs a complete refurb including the heating system. The existing system is oil fired warm air heating using a boiler original to the house (1965). The hot water is supplied by a immersion heater. Nearly everyone in the village is on oil. I have had a high level quote of £5k for a new oil system including tank and rads but as I'm starting from scratch I would prefer an ashp to avoid the hassle of oil and on the basis they would have the same install costs. However, I've had a quote of £13k for a ecodan ashp including 15 rads which nearly knocked me off my feet. The same guy also quoted me £9k for an oil fired system so I think he may just be very expensive. Another guy came to quote and said ashps only work in purpose built houses and cannot be retrofitted and didn't even price the job. He wanted to install an electric boiler which I refused on the basis of running costs. So is it realistic to install a ashp for around £6k and would it work in a 1965 larger style 3 bed semi? Your thoughts would be really appreciated.

TiredGeek

If you're doing a COMPLETE refurb then an ASHP may well work for you.
For best results you'll need to insulate very heavily and make sure there's no drafts, underfloor heating would also be a very sensible option. The lower you can keep the water temp the more economical it will be to run.....


The bad news is for a well fitted EcoDan system I'd guess £10k plus is probably in the ball park.
When you're comparing systems don't forget that not all are created equal, quite a lot of them use a back up heater for when the ASHP can't cope, the EcoDan doesn't and so in the long run is arguably cheaper to live with. YMMV.


If you're even thinking about this technology then you need to read all the threads on here, and some of the ways things can and do go wrong with installation (read mine, it's a doozy ).


In the end, research research and research a bit more

matelodave

There's no reason it shouldn't work in a 1960's style house.

Improving the insulation should be your first priority, cavity wall, uprating the loft to 300mm, double glazing and draught proofing and even underfloor insulation (if you've got suspended ground floors) will allow you to properly size the heating system for whatever heat source you decide install.

Bear in mind that an ASHP runs at much lower temperatures than an oil or gas (lpg) system so rads or underfloor heating has to be sized appropriately so the heating system might cost a bit more than a high temperature system.

Regarding the heat source you would have to take into account the whole cost of the installation, ie an oil boiler will require a tank, space to install it, possibly a concrete base and pipework, lpg might have similar installation costs although you generally rent the tank. Even an ASHP will need to have a space to accommodate the compressor unit.

We had a Daikin 11kw ASHP installed just over three years ago and it cost us about £7.5k, whereas an oil boiler and all it's bits was about £3.5-4k so there was a premium of about £3.5 to £4k to have the heatpump. We've had three cold winters with it and it's our only source of heating and we are quite comfortable in our 140sq.m detached bungalow. We don't have to store any fuel or get deliveries like the rest of the people who live around us.

We are at home all day so it works for us although I'm not certain that it would be so successful if you just wanted heat in the mornings, evenings and weekends as it is quite slow in heating rooms from cold because of the lower temperature water flow through the system so it's better for continuous heating and just reducing the temps rather than turning on and off.

If you want more info I'm happy to share it with you if you want to PM me

[Deleted User]

helpjack wrote: »

Hi everyone, Long time reader, first time poster on the thread! I have recently bought a house in a village without mains gas so looking for advice. The house needs a complete refurb including the heating system. The existing system is oil fired warm air heating using a boiler original to the house (1965). The hot water is supplied by a immersion heater. Nearly everyone in the village is on oil. I have had a high level quote of £5k for a new oil system including tank and rads but as I'm starting from scratch I would prefer an ashp to avoid the hassle of oil and on the basis they would have the same install costs. However, I've had a quote of £13k for a ecodan ashp including 15 rads which nearly knocked me off my feet. The same guy also quoted me £9k for an oil fired system so I think he may just be very expensive. Another guy came to quote and said ashps only work in purpose built houses and cannot be retrofitted and didn't even price the job. He wanted to install an electric boiler which I refused on the basis of running costs. So is it realistic to install a ashp for around £6k and would it work in a 1965 larger style 3 bed semi? Your thoughts would be really appreciated.

Of course an ASHP work in your house but you must insulate as best you can e.g. cavity wall, eliminate drafts bar controlled ventillation, loft, underfloor etc

Keep looking for a good installer, go and see working systems, anyone in the vacinity got one...?

What I would say is do your research and don't skimp on the right install.

There are massive long term savings to be had over oil & LPG, even over mains gas [taking capital cost out the equation].

Currently paying under £3 a day to light, cook, heat [all day], hot water in November on the sub zero days in Scotland. Even when it has been double digits below zero it has never gone above £5 day. And that is in a 100+ year old former station with rubbish insulation compared to a modern rabbit hutch.

What we like about about it is the house is always warm, none of the yo-yo-ing trying to eek out the last drop of LPG and oil. Done the oil and lpg thing in the past, never ever again...

PS Oh yes and stick to the big established names for warranty and support. Avoid carp that rymes with something that once lived on the roof of a truck, heatking, thermoking :rotfl: