Warm air duct heating to air-condition

movilogo

In my home there was a warm air heating system (using Johnson Starley boiler) and rooms had vents. Few years back I got rid of that boiler and fitted traditional wet radiators.

Now with current heatwave, I'm wondering whether I can leverage the remaining duct system for centrally aircondition the house!

If so, what kind of aircondition unit I need?

The old boiler was in an airing cupboard in downstairs in middle of house. But it does have a pipe going towards the external wall to take the flue out (when old boiler was there).

QrizB

If so, what kind of aircondition unit I need?

A system with an air handling unit (AHU). Rare in UK domestic properties but a little more common in commercial ones.

You'll probably need to speak to a specialist HVAC (heating, ventilation and air conditioning) company, not a man-and-van business.

Albermarle

https://forums.moneysavingexpert.com/discussion/comment/82105500#Comment_82105500

@QrizB

Out of interest, why would the OP need a commercial type AHU?

I thought if you fitted a standard domestic air to air system, you could also fit ducts to distribute the cold/warm air around the house. Of course for a large house one air con unit would not be enough, but I thought with a duct system you could cool/warm more than one room with each aircon unit ?

QrizB

I thought if you fitted a standard domestic air to air system, you could also fit ducts to distribute the cold/warm air around the house.

I'm not aware of anyone having done that (unless you count one forumite who has a fan in the window between his kitchen and his conservatory). There's no obvious way to adapt a conventional wall-mounted unit to instead blow air through ducts, short of scratch-building an AHU around it.

The only domestic UK ducted aircon installation I'm aware of is this one, and it used an AHU:

https://www.revk.uk/2021/10/new-mitsubishi-ducted-air-con-with.html

I'll add that in the end RevK wasn't very happy with that system and had it replaced. I don't think he's ever blogged about exactly what he replaced it with.

Albermarle

https://forums.moneysavingexpert.com/discussion/comment/82105774#Comment_82105774

I am now better informed 😀

More seriously if in future you wanted to avail your self of the £2500 grant for air to air systems, then you would probably have to fit a ducted AHU system. AIUI to get the grant ( starting next year) it has to 100% replace your current heating system. Unless you had a very small house/flat that would mean it working in multiple rooms.

ComicGeek

Very common system in North America, but limited companies sell something similar in this country on this scale.

Unico have their own system https://www.unicosystem.co.uk/ which then links to an external condenser which provides the heating and cooling input to the air system.

danrv

https://forums.moneysavingexpert.com/discussion/6680027/warm-air-duct-heating-to-air-condition

It's likely to be galvanised steel ducting. My property has the same although the warm air heater was electric.

I was looking at doing a similar retrofit for heating and the main issue was with insulation. Ducted aircon usually uses foil tubing and it would've been difficult to fit this inside the steel ducting.

After a brief discussion with the aircon company, I went with multisplit aircon for heating and cooling.