Air con is the word British owners use and it covers two entirely different purchases. One is an appliance on castors that plugs into a socket. The other is a fitted system with an outdoor unit, a pipe run and a certificate, installed by an engineer who is legally required to hold a qualification. Almost every confusing price comparison comes from those two being quoted as if they were the same thing.
What an air con quote should contain
The specified cooling and heating capacity, the indoor unit type and where it goes, the outdoor unit position and how it is mounted, the pipe run length and route, the electrical arrangement and who certifies it, whether making good is included, the commissioning, and the service interval with its price. A quote that is one line and one number is a starting point rather than an offer.
Why aircon installation cost varies between houses
The building sets the price. A bungalow with the room on an outside wall and a consumer unit in the hall is a straightforward day. A first floor bedroom over a conservatory, with the only sensible outdoor position at ground level and a solid wall between, is a different job with the same equipment in it. Neither firm is wrong; they are pricing different work.
How much does air con cost to run?
A modern inverter system draws most power when it is pulling a room down to temperature and much less once it is holding it, which is why an oversized system that short cycles can cost more to run than a correctly sized one. A reverse cycle unit that also heats changes the calculation again, because it is then in use in months when a cooling only system is switched off.
What to do before you ask for prices
Decide which rooms and in what order, find the likely outdoor position and check what is on the other side of that wall, look at whether the consumer unit has a spare way, and note anything that will need access equipment. Half an hour of that turns a vague enquiry into a brief, and a brief is what makes three quotes comparable.
Questions people ask about air con cost
What is the difference between air con and aircon?
Nothing. Both are the everyday British shorthand for air conditioning. The difference that changes the price is fixed against portable, not spelling.
Is an air con quote binding?
A written quotation for a specified job is normally an offer that becomes binding when you accept it, unlike an estimate. What matters more in practice is whether the quote describes the job precisely enough that both sides agree what was included when something is found behind a wall.
Should I pay a deposit?
A deposit for ordered equipment is normal. Paying for the whole job before any work is done is not, and staged payments tied to delivery, first fix and commissioning protect both sides. Card payment on the deposit gives you protections that a bank transfer does not.
Does air con add value to a house?
It is better understood as something that changes how a house is used rather than as an investment. A reverse cycle system that heats a loft room in winter and cools it in summer is doing work all year, which is a different proposition from a cooling only unit in a room that overheats for three weeks.