A four-bedroom or big three-bedroom flat can have four indoor units. Chemical wash for all four is $425 on our price list, and for a household watching its spending that is a lot to find in one go. So the question we hear is a practical one: if the budget only stretches so far, which units should get the deeper clean first, and is it cheaper to do two now and two later?
The short answer is that doing them in stages is allowed and sometimes sensible, but it is not cheaper. This guide shows the arithmetic using only the prices we publish, then gives a way to choose which units go first.
The published prices, side by side for four units
These are the figures on our price list, and the displayed price is the final price:
- General servicing: $45 for 1 unit, $70 for 2, $95 for 3, $115 for 4, and $25 per unit from 5.
- Chemical wash: $135 for 1 unit, $245 for 2, $345 for 3, $425 for 4, and $100 per unit from 5.
- Chemical overhaul: $200 for 1 unit, $370 for 2, $515 for 3, $640 for 4, and $150 per unit from 5.
For a home with four units, that means $115 for a general service of all four, $425 for a chemical wash of all four, and $640 for an overhaul of all four. The gap between the first two is $310. That gap is the real budget decision, and it is why people start looking for a middle path.
Why splitting the visits costs more, not less
Every price in the tables above is set by the number of units in the booking. The more units you book together, the lower the price per unit. If you split four units into two visits of two, each visit is a two-unit job, so you add the two-unit price twice.
For a chemical wash that is $245 + $245 = $490, against $425 for all four in one visit, which is $65 more. For general servicing it is $70 + $70 = $140 against $115, which is $25 more. The same pattern holds for an overhaul. We are not adding a fee for splitting. You simply stop getting the lower per-unit rate that a bigger booking earns.
That does not make splitting a mistake. If $65 extra buys you the ability to spread the spending over two months, it may be the right call. It should just be a decision you make knowing the cost, not a surprise.
The middle path: wash some units, service the rest
There is a cheaper option than washing everything, and it keeps your priorities intact: give the units that need it the deeper clean, and keep the others on a general service. Adding up our published rows for a four-unit home, with the chemical wash booked for the units that need it and general servicing for the rest:
- Wash 1 unit ($135) and service the other 3 ($95): $230 in total.
- Wash 2 units ($245) and service the other 2 ($70): $315 in total.
- Wash 3 units ($345) and service the remaining 1 ($45): $390 in total.
Two things to be clear about. First, those totals are the published rows added together, as if the two jobs were booked separately. If you want both in one visit, WhatsApp us the unit count for each job and we will confirm the exact figure before anyone comes out. Second, the quoted price is final, so the number you agree on WhatsApp is the number you pay.
How to choose which units go first
We cannot see your flat, but these are the questions that sort the units into an order. Answer them for each unit and the ranking tends to appear on its own.
- Which unit is giving you a symptom today? A unit that smells musty when it starts, cools more slowly than it used to, or drips has already told you it needs more than a quick service. It goes first.
- Which unit runs the most hours? A bedroom unit that runs every night collects dust and moisture faster than a spare-room unit that is on a few times a month. The hardest-working unit is first in line after the ones with symptoms. If you work from home, our guide on running your aircon all day covers how that changes the schedule.
- Which unit sits closest to the kitchen? Cooking oil carries into the air and settles on the filter and coil. We wrote about this in aircon near an open kitchen. A living-room unit next to an open kitchen usually ranks higher than a bedroom unit at the far end of the corridor.
- When was each unit last opened up? If one unit has had a chemical wash in the last year and another has not been touched in three, the second one is the obvious candidate. A unit that has not been serviced for years is covered in what the first service involves.
The units that are barely used, a guest room or a study that sees an hour a week, come last. They are the best candidates for the cheaper general service while you wait for the next round.
Use the pre-check to settle the argument
Every booking includes our 9-point pre-check, and anything extra it finds is quoted before work starts. For a tight budget that matters in a particular way: you do not have to guess which units need a chemical wash. A sensible first visit is a general service across all four units, at $115, and let the pre-check on each unit tell you which ones are heavy enough to justify a wash next. You then spend the larger amount only on the units where it will make a difference, and you have a real finding rather than a hunch.
The trade-off is honest. If you already know two units are in a poor state, going straight to the wash for those two ($245) saves you the extra visit. If you are not sure, the general service first is the cheaper way to find out.
How often each job comes round
Our published ranges are a general service about every 3 months, a chemical wash every 6 to 12 months, and a chemical overhaul every 2 to 3 years. On a budget you do not have to hit the most frequent end of every range for every unit. A rotation works: the heavy-use units sit toward the 6-month end for a wash, the light-use units toward the 12-month end, and the general service keeps the rest in between. Our write-up of chemical wash versus overhaul explains when the deeper job stops being worth it.
If you are weighing a prepaid plan to smooth out the cost, read what to check in a prepaid maintenance contract first. A plan that charges for visits the home does not need is not a saving.
What not to do to save money
- Do not skip a unit that already has a symptom. A musty smell or a weak cool does not improve by waiting. Put it first.
- Do not choose by the cheapest quote alone. Compare what is included, such as the pre-check, the warranty and whether the price is final. Our guide on why servicing prices vary lists what to ask.
- Do not book an overhaul for a unit that only needs a wash. The overhaul is $200 for one unit against $135 for a wash. Use the deeper job where the pre-check calls for it.
A simple plan for four units on a budget
- List the four units and mark any with a smell, weak cooling or a drip.
- Rank the rest by hours of use, then by closeness to the kitchen.
- WhatsApp us the list and the budget you have in mind. Ask for the figure for the wash on the top-ranked units and the general service on the rest.
- Book the visit, read the pre-check findings, and decide the next round from what they say.
WhatsApp 9107 2601 with your unit list and budget and we will confirm which job to expect for each unit, and the exact figure, before anyone comes out.
Common questions
Is it cheaper to wash two units now and two later?
No. Each visit is priced at its own unit count, so two visits of two units cost $245 + $245 = $490 for a chemical wash, against $425 for all four in one visit. Splitting is fine if you need to spread the cost, but it costs $65 more.
Can I wash some units and only service the others?
Yes. Adding our published rows, washing 2 units ($245) and servicing the other 2 ($70) comes to $315 for a four-unit home. For a combined booking, WhatsApp us the unit count for each job and we confirm the exact figure first.
Which unit should I do first?
The one with a symptom, such as a musty smell, weak cooling or a drip. After that, the unit that runs the most hours, then the unit closest to the kitchen.
How often does each job come round?
General servicing about every 3 months, chemical wash every 6 to 12 months, and chemical overhaul every 2 to 3 years.
Is the quoted price final?
Yes. The displayed price is the final price, and the 9-point pre-check is included with any booking. Anything extra it finds is quoted before work starts.
Related reading: full price list · aircon chemical wash · how long servicing takes