A proper air conditioning quote names the exact indoor and outdoor units and their output, shows where each will go and how the pipework and condensate will run, and spells out the electrical work, commissioning, warranty registration and VAT. If a quote leaves any of those out, you are not comparing like with like, and the gap usually turns into an extra charge on the day.

Why the detail matters

Two quotes for “a 3.5kW system in the bedroom” can describe very different jobs. One might be a quiet, efficient unit with a short, concealed pipe run and a dedicated electrical circuit. The other might be a cheaper unit, a long run in plastic trunking across the front of the house and a note at the bottom saying “electrics by others”. Both say 3.5kW. Only a line-by-line quote shows you the difference.

A detailed quote also protects you. It is the document you go back to if something is not done, and it shows the installer has actually looked at your property rather than pricing from a photo. If you are still choosing who to invite, our guide on how to choose an air conditioning installer covers the checks to make first. You can also start with an air conditioning quote from us and use it as a benchmark.

The survey behind the quote

A reliable quote starts with a survey. The installer should measure the room, note which way it faces, look at the glazing and insulation, and ask how you use the space. A south-facing loft room with large windows needs more cooling than a north-facing bedroom of the same size. This is a heat load assessment, and it is what stops you ending up with a unit that runs flat out all summer or one that is far bigger than it needs to be.

The surveyor should also check where the outdoor unit can sit, how the pipes can reach it, where the condensate can go and how the electrical supply will be run. If a quote arrives without anyone having looked at these, treat the price as a guess.

Line by line: what the quote should show

Line on the quote	What it should say	Why it matters
Indoor units	Make, model number and type (wall mounted, ceiling cassette, ducted, floor console)	Same output can mean very different noise, efficiency and warranty
Outdoor unit	Make, model number and whether it serves one room or several	Multi-split and single-split systems are priced and perform differently
Output	Cooling and heating output in kW for each room	Confirms the unit is sized to the survey, not guessed
Efficiency and noise	Energy ratings and sound levels from the manufacturer’s data	Affects running costs and how noticeable the unit is at night
Refrigerant	The refrigerant the system uses	Tells you what future servicing will involve
Positions	Where each indoor and outdoor unit will be fitted	Avoids surprises about sightlines, noise and access
Pipe run	Route, approximate length, concealed or in trunking	Longer runs cost more and may need extra refrigerant
Mounting	Wall brackets, ground stand, anti-vibration feet	Affects noise and access for servicing
Condensate	Gravity drain or a condensate pump, and where it discharges	Water has to go somewhere every time the unit cools
Electrics	Dedicated circuit, isolator, certification	A new circuit is notifiable work and must be certified
Making good	Filling holes, sealing the wall sleeve, tidying up, waste removal	Stops draughts, damp and mess
Commissioning	Pressure test, vacuum, refrigerant checks, handover	Protects performance and the manufacturer warranty
Warranty	Length of manufacturer and labour warranty, who registers it	Warranties often depend on registration and annual servicing
VAT	Rate applied and the total including VAT	Makes quotes comparable
Exclusions	Anything not included	The honest part of any quote

The equipment

The quote should name the manufacturer and the full model number of every indoor and outdoor unit. “Premium wall unit” or “3.5kW inverter system” is not enough. With the model number you can look up the manufacturer’s data sheet yourself and check the efficiency ratings, the sound levels and the warranty terms.

Output and sizing

Each room should have a stated cooling and heating output. If one installer quotes 2.5kW for a room and another quotes 5kW, ask each of them to explain their figure. The answer tells you a lot about how carefully they surveyed.

Positions and the pipe run

The quote should say where the indoor unit goes on the wall, where the outdoor unit goes, and how the refrigerant pipes, cable and condensate will get between them. Pipework can often be hidden in a cupboard or run through the wall directly behind the indoor unit. Where it has to run along an outside wall, it is normally covered in trunking. Longer and more complicated runs take more time and materials, and beyond a certain length the system may need extra refrigerant added.

Condensate

When an air conditioner cools, it takes moisture out of the air, and that water has to drain away. The quote should say whether it drains by gravity to an outside point or needs a small pump. Pumps are sometimes unavoidable, but they add a part that can make noise and need maintenance, so it is fair to ask why one is needed.

Electrics

Most split systems need their own electrical supply from the consumer unit with a local isolator. Adding a new circuit is notifiable work under the Building Regulations in England, so it should be done by a qualified electrician and certified. If a quote says “electrics by others”, you need to arrange and pay for that separately, and your air conditioning installer and electrician will need to coordinate.

Commissioning and handover

Commissioning is not optional. The installed pipework should be pressure tested to prove there are no leaks, then evacuated with a vacuum pump to remove air and moisture before the refrigerant is released into the system. The installer should then run the system, check its operation and show you how to use the controls. Skipping these steps is how systems lose refrigerant and fail early.

Warranty and servicing

Check the manufacturer warranty length and whether it depends on the installer registering it or on annual servicing. Many manufacturer warranties require a regular service, so it is worth knowing that before you sign. Our air conditioning servicing page explains what a service involves.

Legal and paperwork points to look for

• F-Gas certification. Anyone installing a split system handles refrigerant, so the company and its engineers need F-Gas certification. Ask for the company’s certificate number and check it. We are Refcom F-Gas registered, REF1024550.
• Electrical certificate. You should receive certification for the new circuit.
• VAT. HMRC treats most permanently fixed air conditioning units in homes as air source heat pumps for VAT purposes, and those currently qualify for the zero rate on energy-saving materials until 31 March 2027. HMRC says it depends on the facts of each case, so the quote should state clearly which rate has been applied.
• Permission. If you live in a flat, a listed building or a conservation area, check whether you need the freeholder’s consent, listed building consent or planning permission before the outdoor unit goes up. A good quote flags this rather than leaving it to you to discover.

Extras that tend to appear later

These are the lines most often missing from a cheap quote and added on the day:

• a longer pipe run than the quote assumed, and the extra refrigerant that goes with it
• a ground stand or brackets for the outdoor unit
• access equipment for a high wall or a second floor position
• a condensate pump
• an electrical upgrade because the consumer unit has no spare way or protection is out of date
• making good and decorating around the new wall hole

None of these is unusual. What matters is that they are on the quote from the start.

How to compare quotes properly

1. Line the equipment up. Put the model numbers side by side and check the output, efficiency and noise figures.
2. Match the scope. Check each quote includes the same electrics, condensate arrangement, mounting and making good.
3. Check the pipe route. A concealed run and a run in trunking across the front of the house are not the same job.
4. Read the exclusions. The shortest exclusions list is often the most complete quote.
5. Compare VAT on the same basis. Look at the total including VAT on each.
6. Compare warranties. Look at both the manufacturer warranty and the installer’s labour guarantee.
7. Think about running costs. A more efficient unit can cost less to run. Our air conditioning running costs page explains how to work it out.

How we price it

Installations are quoted as a fixed price after a free survey, so the price you agree is the price you pay. Our quotes name every unit by model, show the positions and pipe route, include the electrical work and commissioning, and list anything that is not included. You can request your air conditioning quote online, and our other rates are published on our prices page. We look after the installation ourselves, and our labour is covered by a 12 month guarantee.

Frequently asked questions

Should an air conditioning quote include VAT?

It should state clearly which VAT rate has been applied and give the total including VAT. Many permanently fixed home systems currently qualify for the zero rate until 31 March 2027, but HMRC says each case depends on its facts, so the quote should make the basis clear.

Why do air conditioning quotes vary so much?

Quotes differ because of the equipment chosen, the length and route of the pipe run, how the electrics are handled, access, and what is left out. Lining the quotes up line by line usually explains most of the difference.

Is commissioning included as standard?

It should be. Pressure testing, vacuuming the pipework and checking the system runs correctly are part of a proper installation, and skipping them can shorten the life of the system and may affect the manufacturer warranty.

Can I get an air conditioning quote without a survey?

For a simple single room system you may get a reasonable estimate from photos and measurements. For anything more complicated, or where the pipe route or electrics are unclear, a survey is the only way to get a price that will not change on the day.

Does a new air conditioning circuit need certification?

Yes. Adding a new circuit is notifiable electrical work in England, so it should be done by a qualified electrician and you should receive the certificate for it.

Air conditioning in Hertfordshire, Bedfordshire and Cambridgeshire

If you would like a quote that sets out every line clearly, we survey homes across Hertfordshire, Bedfordshire and Cambridgeshire and put the full scope in writing before any work starts. Request an air conditioning quote online or call 01462 506374.