ASHP with least gubbins inside the house?

[DenkiJidousha]

Hello all. As per the title, are there any ASHP systems on the market with a clear advantage on minimal equipment needed inside the house?

 

Should it matter, the background to my question is a retrofit. We have a reasonably modern and comparatively well insulated home, built with underfloor heating upstairs and down, with a mains gas combi-boiler. I've posted before about our planned 7kW Vaillant aroTHERM ASHP with SunAmp UniQ install which sadly we had to cancel this summer - the installer realised there wasn't going to be enough space in the cramped boiler cupboard after all, fortunately before any work was done.

[dpmiller]

Was this particular AroTHERM split or monobloc? Anything with an indoor Hydrobox is going to take more space, and some units may be less reliant on a buffer tank, depending on your particular system design, temperatures, and volume.

[PeterW]

Any of the monoblocks are fine - control boxes about the size of a ream of paper on the Mitsubishi, think the Panasonic is even smaller. Valve gear will be identical to a boiler.  
 

Why the sunamp..? How big is the  boiler cupboard as I would go with the biggest tank you can fit and save your money. 

[IanR]

I'm guessing its space for the Sunamp/HWC and buffer that you are short of. 

 

How about the loft? Can you make space up there, even if you have to cut a larger hole to get what you need into the area. There are hot water cylinders that can be mounted horizontally.

[DenkiJidousha]

Thanks all, that's helpful - seems no obvious differences then, unless a manufacturer is willing to do a warranty without any buffer?

 

It was the AroTHERM monoblock we were looking at, with a SunAmp rather than HWC due to the very limited space. Then control box, values, buffer, expansion vessel - plus critically working space for doing all the pipework - quite a challenge.

 

There is loft space so in theory room for a horizontal HWC, but the timber re-working seems challenging, and additional pipework would be needed from the ground floor boiler cupboard up through the upper floor - would be cosmetic challenge too.

[DenkiJidousha]

Or another thought - do any monoblock ASHP manufacturers have the buffer in the outside unit? Seems to me that would be useful for the space constrained retro-fit market (even if they have to use more space outside to have a well insulated buffer tank).

[dpmiller]

Some of the Chinese ones have a tank inside, yes. Not sure if it's for buffer or DHW holding tho...