Why cooling power falls exactly when the water gets cold
Cooling capacity is measured under standard test conditions: 15-degree water in, 27-degree ambient air. An ice bath is a far harder job. The colder the water, the lower the refrigerant evaporating temperature, and the less refrigerant mass the compressor moves per revolution. Add a condenser standing in 34-degree air, which raises discharge pressure, and real output lands at about 46 per cent of the brochure number. Every PK figure quoted anywhere on this site already accounts for that, so the 1.5 PK we name behaves like 1.5 PK in your garden rather than in a test chamber.
| Size | Brochure | Real output at 5 °C | Max volume, lid on | Draw | Price |
|---|
| 0.5 PK | 1.4 kW | 0.65 kW | 110 L | 480 W | Rp 14 million |
| 0.75 PK | 2.1 kW | 0.98 kW | 180 L | 700 W | Rp 16.5 million |
| 1.0 PK | 2.8 kW | 1.3 kW | 260 L | 950 W | Rp 19 million |
| 1.5 PK | 4.2 kW | 1.95 kW | 410 L | 1400 W | Rp 26 million |
| 2.0 PK | 5.6 kW | 2.6 kW | 570 L | 1850 W | Rp 34 million |
| 3.0 PK | 8.4 kW | 3.9 kW | 1100 L | 2700 W | Rp 48 million |
The maximum volume column is the largest tub that unit can still hold at 5 degrees in hot lowland Indonesia with the lid on — 33-degree air, 29-degree mains water. In Bandung that figure rises about 20 per cent, in Berastagi about 45 per cent. For your own city, run the chiller calculator, which uses the same model as our survey sheet.
What we do to an imported unit before selling it
- Open it and inspect. Pipe welds, compressor bolt torque and cable routing are checked one by one. A unit whose pipework vibrates against the frame will leak within two years, and we correct that now.
- Replace the sensor if needed. Factory sensors from some suppliers drift 0.8 degrees at low temperature. We compare against a calibrated thermometer and replace anything out by more than 0.3.
- Run it for 24 hours in water. The unit goes on a 400-litre test tub and runs a full day and night, with temperature, current and pressure logged every hour.
- Reject what fails. About one unit in twenty goes back to the supplier. The two commonest reasons are a compressor whose current creeps upward through the test and an expansion valve that hunts.
Factory test condition15 °C water, 27 °C air
Real condition here5 °C water, 33-34 °C air
Real output against brochureabout 46 per cent
Worked example, 1.5 PK4.2 kW brochure becomes 1.95 kW real
Re-test duration24 hours per unit
Rejection rateabout 5 per cent of imported units
Maximum hose run6 metres on insulated hose
Sizing: two tests, not one
A chiller has to pass both. First, its real output at the target temperature must be at least twice the tub's holding load. That margin is not there to sell you a bigger unit; it exists because a compressor running flat out all day ages fast, and the hottest day of the year is not the average day. Second, it must pull a full tub from local mains temperature down to target within eight hours, so a first fill can run overnight. A 400-litre tub in Jakarta with a 516-watt load therefore lands on 1.5 PK rather than the 1 PK that a holding calculation alone would allow.
The four installation mistakes we see most
- The unit boxed in on every side. The condenser breathes its own exhaust and loses up to 30 per cent. It needs 60 centimetres clear on the discharge side and 30 on the intake.
- Hose run too long. Past six metres, heat gain and pressure loss start to matter; past twelve we would rather move the unit than enlarge the hose.
- No stabiliser where the voltage sags. A compressor run below 180 volts draws more current and runs hot. Damage from this is excluded by every warranty, ours included.
- Condenser fins never washed. Every three months on the coast, every six inland. Fins blocked with dust and salt raise discharge pressure and cut capacity long before anything actually breaks — the schedule is under maintenance and service.
When an imported on-off unit is the wrong buyIf the tub is near a bedroom, 52-58 dB at one metre will be audible and the compressor will start a dozen or more times a day. If your local voltage regularly falls below 190 volts, an on-off unit will struggle. In both cases the Arctic inverter chiller is the better answer despite the price. And never use a quarter or half-PK aquarium chiller on an ice bath: those are designed for a 200-litre tank in an air-conditioned room and in an open garden they hold water at 16-19 degrees.
Price and what the figure includes
Re-tested imported units run Rp 14-48 million from 0.5 to 3 PK, including installation in Java and Bali, insulated hose to six metres, the mounting plinth and the on-site cold test. If your tub was built by somebody else we still measure it and calculate its load first — an uninsulated tub can need a chiller twice the size. Full comparison with the inverter line and every other price is on the pricing page.
Can I buy only the chiller for a tub I already own?
Yes, and that is about a quarter of our chiller sales. Send photographs, internal dimensions and whether the walls are insulated. If they are not, we will tell you what PK that implies and usually suggest adding external insulation first, because it is far cheaper than going up two sizes.
How long does a chiller last?
Eight to twelve years for a compressor on stable voltage with the fins washed on schedule. What ages first is normally the circulation pump, at five to seven years, and replacing one costs under Rp 2 million.
Should I switch it off when I am not using the tub?
Usually not. Holding cold water costs 4.9 kWh a day on a 400-litre tub; cooling it again from scratch costs about 3 kWh in one go plus eight hours of waiting. If you immerse three times a week or more, leave it running.
Can R32 be topped up in a small town?
Yes. R32 is used across new domestic air conditioning, so it is available almost everywhere including district towns. That availability is one of the reasons we chose it over refrigerants stocked only in big cities.
What happens if the PK is too small?
The water stops falling at some temperature, usually 9 to 14 degrees, while the compressor runs without pause. Its life shortens, the electricity bill is higher than a correctly sized unit, and the result is still wrong. That is why we decline to sell a unit smaller than the calculation, even when asked.
