Two warning signs matter more than the monthly figure. The first is high-cost credit: heavy charges on a short agreement, pressure to sign on the day, and a total you cannot square with the install. The second is paying a large sum, or the full price, before anyone has surveyed the rooms. A finance offer is not a survey. This page does not name lenders. Agree the equipment, the pipe route, the drain and the electrics before you attach credit to the job.
A monthly figure before the wall is seen
A surveyed price names indoor and outdoor model codes, where the outdoor unit goes, how condensate leaves, and what electrical work is included. A brochure price with a monthly payment attached has none of that. A deposit that reserves a survey slot is different from paying for the equipment before the wall has been seen. Ask what is refundable if the survey says the job should not proceed. Citizens Advice guidance on home improvements is a useful cross-check before you pay. Survey and spec first. Credit second. This page names no lenders and no representative APR.
Credit does not move the outdoor unit
Interest does not change Planning Portal rules, neighbour noise, or the need for a certified company on the refrigerant circuit. A cheap monthly plan on a condenser that cannot legally sit on that wall is still the wrong condenser. Energy Saving Trust describes the machines as air-to-air heat pumps. Running cost is your electricity. The F-gas work is still a certified company's job whatever the monthly figure says.
Frequently asked questions
Is monthly finance a sign of a bad install?
No. The warning signs are high-cost credit and paying before a survey. A clear agreement, after a written spec, can be a normal way to pay.
Should I pay in full to secure a summer install?
Pay what the written price says is due, after the survey has fixed the spec. Paying the full price before anyone has seen the wall is the step to refuse.
Which lenders are acceptable?
This page does not name lenders. Read the total charge, the term, and whether the installer and the credit agreement are people you can actually contact.
What if the survey later finds a pump or scaffold?
If the survey later finds a pump, scaffold or a consumer unit upgrade, the monthly figure was for a different job. High charges and a short term are a warning, whatever the monthly sum looks like.
Does the finance payment include the electricity?
Running cost is your electricity. It is not included in the finance payment unless a contract explicitly says so, which would be unusual and worth reading twice.
What if the credit pays a retailer I cannot find again?
Finance that pays a retailer you cannot find again leaves you with the debt and without a commissioned system. The agreement should match the price: who installs, who is F-gas certified, when they install, and what happens if parts are late. A same-day signature, a discount that vanishes if you read the agreement overnight, or a refusal to write the model codes down, is a reason to stop.
Core buying guides
Start with these high-intent guides, then dig into the rest of the library.
Related guides
Sources and further reading
How this guide was prepared
This guide was written by the Local AC Installers Editorial Team. We compare official guidance, legislation and established consumer information, separate general information from project-specific advice, and show publication dates and sources. We do not accept installer accreditation claims at face value.