Ashp & sahp combined system

martindias

Yep definitely looking to put in underfloor insulation - think this will have to be me with a mate - retrofit insulation beneath the floorboards, between the supporting joists. Then get a good underlay and thick carpet!

zeupater

martindias wrote: »

The house heat requirement Is estimated at 30784 KWh being approx 216 sq meter. The engineer has recommended a 16KW LG Terma VC ASHP and a BMTB 300 SAHP solar assisted pump to go with it - to augment the water heating and a system that can run throughout the year to provide constant hot water. Both are apparently eligible for the Renewable Heat Incentive payments.

Hi

It looks like the SAHP you mention is a thermodynamic panel solution ... have you been supplied any performance specifications & been assured that it has current certification for inclusion into domestic RHI against the MCS or Ofgem product eligibility databases ?

HTH
Z

martindias

"have you been supplied any performance specifications & been assured that it has current certification for inclusion into domestic RHI against the MCS or Ofgem product eligibility databases "

No - thanks for the prompt - I'll ask

zeupater

martindias wrote: »

"have you been supplied any performance specifications & been assured that it has current certification for inclusion into domestic RHI against the MCS or Ofgem product eligibility databases "

No - thanks for the prompt - I'll ask

Hi

Whilst asking, try & establish why the thermodynamic water heating has been quoted for & what the cost of this option actually is ....

I've looked at the (US) version of the spec and it simply looks like a small HP linked to a passive (flat plate) evaporative heat exchanger with a large capacity water store and loads of resistive heat (immersion) power provision ...

The heat pump spec that I've found (US) excludes a performance curve or any mention of COP or SCOP with mention only being given to max heat provision (BTU) and average power consumption (W), which as a guide to performance for potential customers is about as useful as a chocolate teapot!!

Are you aware that the quoted ASHP can be installed to provide DHW as well as space-heating which could provide a much simpler (/cheaper, depending on what this setup costs!!) option than laying out on two heat-pumps.

Next question ... as you mention floor insulation as a separate project, I take it that you're not looking at underfloor heating and will be relying on (existing?) radiators .... if so, is the surface area of the radiators being upsized to compensate for lower heat circuit operating temperatures and importantly, that this is included in the price quoted? ....


Must say, my <BEWARE> radar has pinged a number of times already on this one, so take care and make sure you do some robust research before committing to this setup as described!! ...

HTH
Z


ps .. I quickly looked at the MCS product database yesterday and found it very interesting ... suggest you do the same!!

martindias

Thanks....I will. The second quote I had saw no need for the ASHP. The house renovation oxides a substantial extension...all the new build will be sold for with underfloor heating. The older downstairs, 2/3rd of the original house, will remain suspended wooden floors.

By the way start is the MCS product database?

zeupater

martindias wrote: »

Thanks....I will. The second quote I had saw no need for the ASHP. The house renovation oxides a substantial extension...all the new build will be sold for with underfloor heating. The older downstairs, 2/3rd of the original house, will remain suspended wooden floors.

By the way start is the MCS product database?

Hi

You can get cost assistance for some energy saving products through the RHI scheme (Renewable Heat Incentive) through a quarterly payment for set a number of years, however, there are application requirements (have a look at Ofgem RHI site) based on installers and certain certified products .... a list of certified products is available as a downloadable file on the Ofgem site but a searchable database is also available on the MCS (Microgeneration Generation Scheme) website .... https://mcscertified.com/product-directory/ ...

HTH
Z

martindias

I have finally made a decision after 4 quotes and endless conversations with heat engineers. Going for an LG ASHP R32 14 KW 300 LITER TANK £11529. Then I took the plunge and went for 14 JA 310w solar panels too, £7296 including a 2.4 kw upgradable battery pack rather than the SAHP. Being installed in Feb. Thanks for all your advice and help - certainly helped me take the BIG step.

pile-o-stone

martindias wrote: »

Currently I am on gas central heating and the boiler is a thrillion years old - actually now it's in a skip waiting to be carted away.

Are you on mains gas? If so, then I don't understand why you're installing a heat pump for £16k when you could have an efficient gas boiler for a couple of grand. You then won't have to worry about oversizing the radiators to accommodate the much lower water temperatures from a heat pump. The running costs are supposed to be similar between a gas boiler and heat pump, though if you have to run the heat pump hotter, especially with a Victorian home, then it will cost a lot more to run than gas.

Coastalwatch

pile-o-stone wrote: »

Are you on mains gas? If so, then I don't understand why you're installing a heat pump for £16k when you could have an efficient gas boiler for a couple of grand. You then won't have to worry about oversizing the radiators to accommodate the much lower water temperatures from a heat pump. The running costs are supposed to be similar between a gas boiler and heat pump, though if you have to run the heat pump hotter, especially with a Victorian home, then it will cost a lot more to run than gas.

Er, but not exactly Green though, is it?

JKenH

pile-o-stone wrote: »

Are you on mains gas? If so, then I don't understand why you're installing a heat pump for £16k when you could have an efficient gas boiler for a couple of grand. You then won't have to worry about oversizing the radiators to accommodate the much lower water temperatures from a heat pump. The running costs are supposed to be similar between a gas boiler and heat pump, though if you have to run the heat pump hotter, especially with a Victorian home, then it will cost a lot more to run than gas.

Good pragmatic money saving advice which is what people on this forum are looking for.