How I'd choose someone to service my air-con

I'd pick whoever can show me why my air-con needs the job they're quoting, because the words on the invoice are slippery and the unit is above my head. The moment I'd slow down is when a basic wash turns into a chemical one.

Three jobs with nearly the same name

A basic wash, which you'll see called standard or regular, is mostly the bits a person can reach. One marketplace that sells these services lists the filters, a wipe of the blower and fan blade, the indoor housing, and a look at the outdoor unit.

A chemical wash goes further, into the evaporator coil. An overhaul takes the indoor unit off the wall and apart. SAYS's explainer makes the case against stopping at the basic job: it "cannot reach the deeper parts of your unit".

Neither is a neutral party, exactly. Recommend.my takes bookings for this work, and the SAYS piece names no technician or company behind its prices. So here are the numbers, with that warning attached.

A wall unit, top of one marketplace's range, in ringgit

The two lists don't agree. SAYS has a chemical wash running up to RM250, where Recommend.my stops at RM150.¹ Either way, a cassette unit in the ceiling costs well above a wall unit on the marketplace's list, so I wouldn't compare a quote without knowing which one it's for.²

The gap per unit isn't scary. It's the sum that gets you, when someone offers to do all five units while they're here.

The question for the chemical wash

The simple version is one a year. SAYS is more careful than that, saying it's "recommended annually for heavy users or when symptoms of deep dirt build-up appear".¹

That gives me something to ask about, because its list of symptoms is one a homeowner can actually check:

• weak airflow, even on a high fan speed
• a musty smell on switching on
• water dripping from the indoor unit
• visible mould on the fan or coil

So I'd ask which of these they've seen, and I'd want to see it too. A good technician with a torch should have no trouble with that. A dirty coil is a dirty coil.

I'm less sure about warm air, which is also on SAYS's list.¹ My guess is that warm air and dripping could have other causes, so I'd also ask what they'd ruled out, and I'd be happy if the answer was a bit long.

SAYS also puts a basic wash at every three to four months.¹ It doesn't say where that comes from, and I'd guess a bedroom unit that runs at night and a shop's unit that runs all day don't get dirty at the same pace. I'd go by what comes out of the filter.

Where did the gas go?

This is the question I'd get a bit awkward about. As I understand it, the gas runs round a closed loop and isn't burnt off like petrol, so a unit that's short of it has either been short from the start or has lost it somewhere.

I couldn't get an official page on this to open, so that's my understanding and not a finding. A technician may well correct me.

There's a hint in how one seller prices it, though. Recommend.my's chemical cleaning comes with a free top-up within a limit, and that offer doesn't apply to a unit with a gas leak.² So a leak is a different job from a top-up, on the seller's own list.

Its paid rate, for what it's worth, is RM20 or RM40 for a set bump in pressure, depending on the gas.²

I'd ask for the reading before and the reading after, and whether anyone looked for a leak. I wouldn't try to judge the reading myself, because the target pressures on that page don't match what its author gave in a reply underneath it.²

What I'd want on the quote

A short message is enough, as long as it settles the things people end up arguing about afterwards. I'd want it to say:

• the price per unit, and which kind of unit
• what gets cleaned, in words: filters, coil, housing, drain
• whether gas is included, and up to what limit
• what happens to any call-out or inspection charge if I go ahead
• the company's name and an address

That charge is real. Recommend.my lists a basic troubleshooting fee of RM80, waived if the repair is done on the same visit.²

The name and address matter for a duller reason. The Consumer Protection Act implies a guarantee that services to a consumer are carried out with reasonable care and skill, and its tribunal hears claims of up to RM50,000, with some limits.³ I can't picture filing one against a phone number.

The same Act says that if neither the contract nor your past dealings set a price or a way of reaching one, you're not liable for more than a reasonable one, and your only remedy there is refusing to pay the excess.³ That's a thin thing to rely on, with a man and a ladder in your living room. I'd settle the price first.

When I'd walk away

I'd walk if a chemical wash was announced before the cover came off. I'd walk if gas was topped up on every visit and nobody ever got curious about why. And I'd think twice about anyone who won't put a price in writing for a job this simple.

A fair price is harder. I'd use those two published lists as a rough fence and not a promise, because I'd expect prices to move with the area and the state of the unit, and I can't tell you how much.

What I'd ignore is the star rating on its own. It tells me people were pleased on the day, and I'd guess a badly done service takes longer than that to show.