Mini-split repair in Scarborough, Durham and the GTA
Ductless systems fail differently from central equipment. There is no furnace door to open and no obvious burner to inspect — most of the diagnosis happens in the controls, the refrigerant circuit and the condensate path. Metropolitan Heating and Air Conditioning works on all makes and models across Scarborough, Durham Region and the GTA, and has been at it since 1979.
Call (416) 283-5698, Monday to Friday 8:00 AM to 4:00 PM.
Start with the code the head is flashing
Almost every ductless indoor unit reports faults by blinking its operation, timer or defrost lamps in a pattern, or by showing a code on the display or the handheld remote. That pattern is the single most useful piece of information you can give us, because manufacturers map codes to specific circuits — a communication fault between indoor and outdoor units, an open or shorted thermistor, a high-pressure trip, an outdoor fan fault.
Count the blinks, note which lamp is blinking, and have the model number from the label on the indoor head or the outdoor unit. With those two things we can usually arrive with the likely part on the van rather than ordering it after the visit.
The faults that account for most ductless calls
- Water dripping from the indoor head. The most common ductless call by some distance. The condensate drain has blocked with biofilm and dust, or the line has lost its continuous fall, or a lift pump has failed. The water backs up in the drain pan and comes out of the bottom of the head.
- The head runs but barely cools or heats. Usually a dirty filter or a fouled indoor coil, low refrigerant charge from a leak, or an outdoor coil that cannot reject heat. Refrigerant is not consumed — if it is low there is a leak, and adding gas without finding the leak only defers the same visit.
- Outdoor unit runs, indoor head does nothing. Often a communication fault on the interconnecting cable, or a failed indoor board or fan motor.
- System starts, runs a few minutes, stops. A pressure trip or a thermistor reading out of range. On a multi-head system it can also be one head's expansion valve sticking and unbalancing the others.
- Ice on the outdoor coil in winter. Some frosting is normal on a heat pump and the defrost cycle clears it. Ice that persists through defrost points at a defrost sensor, a reversing valve, or a unit sitting too low in snow or melt water.
- Grinding or rattling from the head. Mechanical — a fan bearing or a loose blower wheel.
Shut the system off at the breaker and call rather than running it if you see scorching, smell burning, or find water anywhere near the electrical connections.
Why an inverter takes longer to diagnose
On a fixed-speed system, the compressor is either running or it is not, and pressures tell you most of the story quickly. An inverter varies its speed, so pressures and temperatures are only meaningful alongside what the board is commanding at that moment. A reading that looks like a low charge at 30% compressor speed can be perfectly normal.
That is why a proper ductless diagnosis means putting the system into a known operating mode, letting it stabilise, and reading refrigerant pressures, superheat or subcooling, coil temperatures and current draw together — then comparing them against the manufacturer's data for that model. It takes longer than a central system, and skipping it is how a good board gets replaced for a fault that was actually a thermistor.
Parts, boards and system age
Ductless parts availability varies sharply by brand and age. Filters, fan motors, thermistors and drain pumps are generally obtainable. Inverter control boards and compressors for older or discontinued models often are not, and on some systems the board is the majority of the cost of a new head.
Repair is usually the right call on a system under roughly twelve years old with one identifiable fault. It stops being right when the compressor has failed, when the system runs a refrigerant that is no longer produced, or when the board for your model is discontinued. We will tell you which of those you are in and price the repair against a replacement side by side. Financing is available through Vista.
Book a mini-split repair
Call (416) 283-5698 weekdays 8:00 AM to 4:00 PM, or send us the model number and the fault code. See also all ductless services and heat pumps. Licensed and insured, all makes and models, in Scarborough since 1979.