ASHP – Should do better - Must Do Better

lardconcepts

richardc1983 wrote: »

Have a look at this picture for example of what happens when installed in an enclosed space

I'd love to, but unfortunately your pics don't work, nor can I see them on the forum you linked to, unless signed in. And it's proved totally impossible to register! I've tried all the browsers I know of, but the signup page just keeps telling my I've not completed the form - I definitely have! So I'll have to take your word on it being a bad idea

rogerbanana wrote: »

hello lardconcepts,

this quote you have seems a bit over the top.

the one i have for a fourbed detached,cavity wall ins. using a 12.5 kw unit is under £5000, fully installed.

Things just got better - when I told him it was ONLY for heating, not hot water, the quote dropped a fair bit. Now we have...

• 1 x Nibe 2015 11 kW heat pump
• 1 x Nibe SM05 control unit
• 1 x Nibe ELK 5 kW back-up unit
• 1 x 200 litre buffer tank
• Anti-freeze solution
• Connection to the existing heating
system supplied by others
• All electrical connections and certification
• Commissioning the system
• Installation registration on the MCS
database

Total inc VAT: £6,926.9
Then once the RHI premium incentive of £850 is taken into account, that brings it to £6076.

That's about the point at which it makes sense for us - our "target" figure was £6k. Because they are MCS, it does seem a little bit higher, BUT... it means there's some chance that we'd also get any RHI starting from 2012.

What do people think of the spec for this revised figure?

paceinternet

Unfortunately, this thread covers a lot of subjects and over a long time, so "lardconcepts", you may have covered this elsewhere, but:
1. You must have a heating assessment done for the property to understand what kw are needed over a range of external temperatures for your location, including the likely minimum.
2. You need to get the quote suppliers to tell you, and document, how the system will sataisfy those kw at various atmospheric temperatures, and then estimate how many days/hours you expect to run at the temperatures to arrive at running costs.

The customers that end up unhappy with their systems are usually those that fail to recognise how it will run. Particularly ask about "defrosting" cycles and when the "back-up unit" will be used.
It can involve some guessing/estimating, but it is also why you should get this information from more than one supplier.

rogerbanana

paceinternet is right, the whole house is treated as a void to be heated, the "footprint" of the property and the cubic capacity along with the wall area and window sizes are calculated for heat loss. of course, cavity wall insulation and double glazing, loft insulation and floor materials come into it as well.

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if these calculations are done properly, there is no reason why a ASHP system at the correct capacity will cause problems. it is wrong just to wander about with a radiator output / room size calculator table (usually what a gas heating enginner does )trying to assess the temperatures needed from the ASHP. a reputable company will then be able to tell you what temperatures you can expect to be maintained down to below freezing outside.

---

also, the overall running costs can be closely estimated.

Larchwood1

One can read only so much and then get more confused. I'm right at the beginning of this journey and my interest is in a small chalet in Southern Spain, really a one bedroom ground floor of 30 sq m.

Last winter I was cold most of the time, no CH. People say underfloor heating works but most people complain about high electricity costs, probably rubbish insulation too. I'm planning a renovation this winter and need to decide straight electricity underfloor or ASHP.

Worst month is January highs of 16 and lows of 11, lowest recorded low 1 celcius. Wind and insulation probably the biggest problems.

Noise louder than your average air conditioner is probably going to upset the residents.

I hadn't considered an ASHP as a water heater too.

It may seem daft to look at those temperatures and say I was cold, but the building quality is so poor and the tiled floors so inhospitable that at no time was in cosy.

All advice welcome. Any personal experiences of installing in Southern Spain, good or bad contacts etc welcome. Thanks. PM's welcome.

John

Cardew

Larchwood1 wrote: »

One can read only so much and then get more confused. I'm right at the beginning of this journey and my interest is in a small chalet in Southern Spain, really a one bedroom ground floor of 30 sq m.

Last winter I was cold most of the time, no CH. People say underfloor heating works but most people complain about high electricity costs, probably rubbish insulation too. I'm planning a renovation this winter and need to decide straight electricity underfloor or ASHP.

Worst month is January highs of 16 and lows of 11, lowest recorded low 1 celcius. Wind and insulation probably the biggest problems.

Noise louder than your average air conditioner is probably going to upset the residents.

I hadn't considered an ASHP as a water heater too.

It may seem daft to look at those temperatures and say I was cold, but the building quality is so poor and the tiled floors so inhospitable that at no time was in cosy.

All advice welcome. Any personal experiences of installing in Southern Spain, good or bad contacts etc welcome. Thanks. PM's welcome.

John

For something that small - equiv to an 18ft x 18ft room - I would have thought an Air to Air heat pump would be your best bet - with the added advantage of air conditioning in the hot summers in Spain.

Noise with any type of heat pump can be a problem in apartments - I would check with the local autorities first.

lovesgshp

Agree with Cardew re an air/air inverter unit for the heating/cooling. Just use a immersion heater with tank for DHW.

Larchwood1

Geotherm wrote: »

Agree with Cardew re an air/air inverter unit for the heating/cooling. Just use a immersion heater with tank for DHW.

Thanks Cardew and Geotherm, but my experience of air heating ain't that great, you know just the fan and wall plug type. Plus I'll have to run some air distribution vents around the place, (not too hard), and those marble floors are going to stay keeping the feet chilled however much I pump in on top!

Will air to air have the look and size of an air conditioner mounted on the wall, like 1m x 1m x 50cm,(just guessing), kind of thing you see everywhere in Spain?

richardc1983

Larchwood1 wrote: »

Will air to air have the look and size of an air conditioner mounted on the wall, like 1m x 1m x 50cm,(just guessing), kind of thing you see everywhere in Spain?

Yes that is correct no air ducts needed.

lovesgshp

Larchwood1.
Interior unit (wall mounted) would be circa 800 x 280 x 200mm L/H/D. Exterior unit 800 x 550 x 300mm. I only have the spec for the IVT Nordic Inverter, but sure you will be able to find other models online.

Jonnat

I work for a company who import and sell MCS accredited Air Source Heat Pumps which will be eligible for the Govt. RHI's in Oct 2012 and qualify for the RHPP's of £850 now. Our most popular "EcoSave" units are 11kW and have a COP of 4 (well 3.97 to be exact). This size is large enough for an "average" home, but that obviously depends on the Heat Assessment Survey. Anyway, to cut a long story short, we survey, supply, fit, commission and guarantee our "average" system for just £6950.00 thats a long way short of £13,000.00 ...