In-duct heat pump for small appartment?

[Mike]

I have a 40m² apartment several floors up that I'll be stripping and modernising in France. Despite the high levels of insulation + airtightness + external window blinds that I'm planning, it will get pretty hot in summer, so I'd like to take the edge off that.

 

There's no chance of installing an external heat pump, due to conservation area restrictions and the only place to hang it being within 2m of a couple of bedroom windows. However it might be possible to draw in and expel a modest amount of air through a duct - either through the external wall, or potentially by lining a couple of old chimney flues - to supply a small internal duct-mounted (or at least duct-fed) heat pump.

 

It could either be connected to in a post heater / cooler to cool the air in the separate MVHR system, or I could connect it to the planned wet UFCH system.

 

Does anyone knows of a suitable heat pump (that's also fairly small, quiet and affordable!) that might work? Ideas welcome.

 

[Ferdinand]

I think you may be looking for the heat pump version of air con unit which works through a single penetration where both pipes go through where all the gubbins is inside.the property and no External unit.

 

@PeterW has some knowledge, but essentially they are an air con or heat pump which sits inside your room and has a single outlet for both pipes and no external unit. Think you are into 1-2k but there is little alternative.

 

Unico Easy is one model I think.

 

I am planning one, but I think @lizzie may have done one already. I plan to fit one in my S facing lounge to manage summer overheat if I keep the current house after probate for mum etc is done and I buy other family out.

 

We touched on them in passing on this thread:

 

 

Edited February 2, 2020 by Ferdinand

[Mike]

Thanks @Ferdinand

 

Your thread and @Jeremy Harris tip mentioned in it (re Unico units) has kept me busy of the day and lead to some more options that might work. All towards the upper end of the price range you mentioned though.

 

Turns out that the  Olimpia Splendid Unico range includes a couple of options in addition to the single room model, with heat pumps, so usable for warming too. One with the option to feed a second unit up to 10m away (perhaps most useful in my case , for bedroom + living room), and another that heats a 50L DHW tank. All of them are based on through-wall-vents being one side of the wall with the aircon unit on the other, rather than having a air supply that can be ducted further. Although I guess I could probably duct them anyway if necessary, subject to adding a condensation trap and using smooth walled ducting.

 

http://zymbo.eu.url (Chinese made, Italian site, PDFs in English) also has several through-the-wall models. There's also Fimer's Windy range, different in that they they use a single hole though the wall with a pair of concentric pipes, though I'm not keen on their styling.

 

Finally, I also found Airwell GCAO, which has a water condenser, rather than using outside air. Consequently it can be located anywhere within range of a water supply, and can be connected to one or more  remote wall or ceiling cooling units. On the downside, it only does cooling, and it also throws away hot(?) water - 90 litres / hour for the base model, if I've understood their data sheet properly - which I may not have, as it suggests the water is only at 15°C (page 6, English in the right hand column). I do wonder if I could turn that into a closed circuit by running the waste water though a DHW tank, and loosing excess heat though a heat exchanger in the MVHR extract duct, with some way of capping the aircon level to match, but there are probably several gaps in that idea, apart from the cost.

 

Anyway, further ideas are still very welcome.

Edited February 2, 2020 by Mike

[tanneja]

@Mike did you look into the water condenser further?

 

It looks like a good concept as external units worry me (planning + neighbours), and are rather ugly.  However the water usage does sound enormous, at least air is free with an air to air system.

Edited June 3, 2020 by tanneja

[tanneja]

Reading more about them, the Olimpia Unico Smart 12HP 9000 seems like a good provision for if an outdoor condenser is too contentious to fit (for aesthetic, PP and likely neighbour reasons).

 

@lizzie did you install one of these units?  If so which size, and did it cool the space as hoped based on the evidence from Jeremy.  If so perhaps one of these for each of the upstairs and downstairs would be enough provision for my renovation.

[Mike]

On 03/06/2020 at 21:31, tanneja said:

@Mike did you look into the water condenser further?

 

It looks like a good concept as external units worry me (planning + neighbours), and are rather ugly.  However the water usage does sound enormous, at least air is free with an air to air system.

 

I've not yet taken a decision to go with any of the options (if any) yet, but compared to the UK per-person average water use (around 140 litres / day), the water usage is high. One installer's web site suggests it may require 140 - 170 litres / hour to cool my 40m².

 

The hottest weather may also coincide with droughts or restrictions on water use.

 

Edited June 5, 2020 by Mike