How Good Is Air Con For Heat And Can It Cut Cost
Most folk link air con with hot days. But many units can also warm a home. In some cases, this can cut your heat bill.
This is not a magic trick. It is how a heat pump works. It can move heat from out side air to in side air.
Fast View
- Heat pump units can be 3 to 6x as good as old elec heat
- For 1 kW of elec use, a unit may give 3 to 5 kW of heat
- Best gain is in mild cold, not deep frost
Why Use Air Con To Heat A Home
Spot Heat
A key win is spot heat. You can heat one room, not the full home. This can cut waste when you do not need all rooms warm.
Fine Temp Ctrl
Most units let you set a set temp and hold it. This can feel more calm than some old rad heat that swings hot then cool.
Zone Use
Some set ups let you heat one zone and keep the rest low. That can be good for sleep, work, or a kid room.
Air Care
Many units have a filter. This can help cut dust and pollen in air. It will not fix all air ills, but it can help some folk.
How Heat Mode Works
In heat mode, a unit pulls heat from out side air and puts it in side. Yes, even cold air has some heat.
This is why it can beat a plug in elec bar heat. A bar heat makes heat from power. A heat pump moves heat with power.
Key Rate: COP
COP is a key score for heat mode. It is:
COP = heat out / elec in
If COP is 3, it means 1 kW in can give 3 kW out. Most new heat pump units can sit near 3 to 5 in mild cold.
COP Mini Sum
| COP | What It Means |
|---|---|
| 1 | Like a basic elec heat |
| 3 | 3x heat for same elec use |
| 5 | Very good in mild cold |
Simple COP Calc
Say a unit gives 4.5 kW of heat and uses 1.5 kW of elec:
COP = 4.5 / 1.5 = 3
Will It Save You Cash
It can. But it hangs on a few facts:
- How cold your area gets
- How good your home is at hold heat
- How new and good your unit is
- Your elec rate, and if you can use off peak
- If you heat one room or all rooms
When It Tends To Win
- Mild win in your area
- You work in one room most of the day
- You can use off peak rate
- You have a new in ver ter type unit
When It May Not Win
- Long hard cold with frost
- Old or weak unit
- Bad loft and wall insul
- You must heat a big home all day
Is It More Good Than Gas Heat
It can be, but not in all cases. Gas cost per kWh is oft less than elec. Yet a heat pump can give more heat per kWh in.
In mild win, it can do well and keep you warm with less total use. In deep cold, gas may still feel more sure and more fast.
Run Cost: A Real Way To Think
Do not just ask "what is elec per kWh". Ask:
cost per kWh of heat
If your elec is 30p per kWh and your COP is 3, then your heat cost is like 10p per kWh of heat (30p / 3).
If COP drops to 2 in cold, heat cost is like 15p per kWh of heat (30p / 2).
Six Things To Check First
- Cli mate: mild or hard cold?
- Insul: loft and wall seal and draft
- Unit spec: new heat pump or old
- Elec plan: off peak rate or flat rate
- Room use: one room vs full home
- Noise: some folk hate fan sound at night
Quick Pros And Cons
| Pros | Cons |
|---|---|
| Can heat fast | Less good in deep cold |
| Spot heat can cut cost | May need wall fit work |
| Can aid air filter | Elec rate can be high |
| One unit for cool and heat | Needs care and clean |
FAQ
Is heat with air con good
Yes. New heat pump units can be very good. A COP of 3 to 5 is common in mild cold.
Is it less cost than old heat
It can be. It most oft wins vs plug in elec heat. Vs gas, it can win in mild cold if COP stays high.
What does it cost per hour
It can vary a lot by unit size, COP, and your elec rate. A good way is to check kW use on the unit and do: kW x p per kWh.
Next Step
If you want to heat with air con, the best move is to match unit size to room size, and check insul and draft.