Air Source Heat Pump for Garden Room

GSDog89

We have a garden room which we use as an office.  The current system is powered by an LPG boiler via a 47kg propane bottle.  It has underfloor heating throughout.

The boiler is now 8 years old and has become very unreliable, with an internal leak now.  Its
also frustrating having to replace the gas bottles.

We are considering an ASHP but have a few questions;-

What sort of ASHP would be most suitable for this?  It will have to work with our underfloor heating.  We do not want a large hot water cylinder as this is not required.  

Is it possible for the ASHP to provide both wet underfloor heating as well as a separate air conditioning, or will we require two entirely separate systems for the air con?

I would appreciate your advice.

Thank you.

Reed_Richards

An air-to-air heat pump could provide heating in cold weather and air conditioning in hot weather.  You would have to forget about your Underfloor Heating pipes.  

Rodders53

Wet ASHP would work with UFH pipes, some need a 'buffer tank' others house the lot in the outside unit.  They can't cool afaik (floor would get cold and humidity condense on floor = slip hazard).

Aircon air to ASHPs can cool air or heat air (a glorified fan heater).  In conservatories they are often 'through the wall' units )relatively noisy) or 'low level' split packs (although other options will depend on the way the conservatory is built and attached to the main dwelling).  

If aircon and heating required a split pack air to air ashp would likely be the best option.  Size / heating and cooling requirements would need factoring in to the design of course.

HOWEVER the $1,000 question is "how is the rest of the dwelling heated" as that may change the suggestions for heating this conservatory.
EDIT must read OP properly. Separate outbuilding garden room not attached conservatory. Doh!

Alnat1

Sounds like a lot of expense for an office which it appears you've already spent a lot on.

GSDog89

Alnat1 said:

Sounds like a lot of expense for an office which it appears you've already spent a lot on.

That is true, although our expense so far has been on maintenance only as the office was already built when we moved here.  We just seem to be spending a lot of money on continuously fixing the current system, and we want an air con unit anyway so we’ll be spending £2k in getting the current system fixed and adding air con unit - may as well change it all for an ASHP that will tackle both demands? 

GSDog89

Thank you for the replies, it sounds like air to air. ASHP may be the way to go then.  I will research some systems that can do both aircon and heating.

Alnat1

Interested in A2A myself for the living room, will work well with my solar PV.  There's more info/advice on the Green & Ethical forum, a few of the regulars on there have them.