Energy efficient air conditioning solution for heating

[Ducky]

Hi all,

I recently went to a friend’s flat who had an air-conditioning unit in his living room which was blowing hot air and keeping it exceptionally warm for such a large living room (6 X 7 meters). He didn’t seem to know much about it other than it is connected to an external unit and apparently kept his energy bills relatively low. It was in the flat when he moved in, and he claims it is an air source heat pump.

I’m exploring ways to get something similar in my living room, as it is also quite large and keeping it warm with electric underfloor heating and a Dyson fan heater is quite costly. So I called a company which installs air source heat pumps and they sent an engineer over yesterday. He explained to me that the external unit of the air source heat pump would need to be connected to my boiler, and the boiler would then be connected to radiators or water based under floor heaters, or heating fans. I decided not to go ahead with it as it would be a massive project, pretty much tearing apart my entire flat to lay the pipes. Note that my flat doesn’t have a gas connection.

I then called my friend, and he claims that his unit is definitely not connected to his boiler. Do you reckon that my friend just has a normal air conditioner in his flat? Or is there a heat pump which has the same energy saving benefits as an air source heat pump, which would only be connected between an external unit and an internal unit which is capable of blowing hot air in winter and cold air in summer (not connected to the boiler)?

Thank you and I appreciate your help with this.
Ducky

 

[stem]

There are two types of systems that utilise air source heat pumps:

1. 'Air to air' which your friend has that is just heating the living room. They are often termed 'air-conditioners' and can work in reverse to cool in the summer.

2. 'Air to water' which replaces a boiler and heats the property using radiators or wet underfloor heating (i.e. pipes)

 

[Ducky]

@stem thank you for that. Air to air (A2A) sounds like what he has, and what I think I would need, considering it would be just for one room. Couple of follow-up questions -

1. It's just an external unit and an internal unit connected with each other, so no need to connect it to a boiler?
2. Does it offer the same energy saving that an A2W heat pump system would?

 

[stem]

1. It's just an external unit and an internal unit connected with each other, so no need to connect it to a boiler?

Yes.

2. Does it offer the same energy saving that an A2W heat pump system would?

The efficiency rests with the heat pump itself, but generally yes. Some manufacturers claim their units run at up to 300% efficiency so you pay for 1kW of electricity but actually get 3kW of heat from it. This efficiency is under perfect conditions though and does drop as the weather gets colder.

The downside is that presently electricity costs about 3 times that of gas per kW so running costs work out about the same.

Some find that the air to air system dries the air and can make it stuffy, or find the airflow / noise annoying.

 

[Ducky]

Thanks @stem