HVAC contractor installed mismatched heating and cooling parts
Contractors often mix incompatible indoor and outdoor units, such as mismatched refrigerants like R22 and 410A or non-communicating compressors with advanced thermostats. This leaves homeowners stuck with high repair costs, lost features like humidity control, and equipment that fails to function properly.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1matching the refrigerant and metering device to the outdoor compressor
- 2changing the TXV or piston
- 3replacing mismatched outdoor compressors or indoor coils
- 4Attempting to salvage the system using thermostat settings or a translator device.
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Theyre running because somebody swapped the indoor coil and never touched the outdoor unit. R22 and 410A coils arent interchangeable, the metering device is wrong and the oils dont mix.”source ↗
“I've done the opposite and in stalled a 410a condenser on a r22 air handler. You need to match the refrigerant and metering device to the compressor (outdoor unit).”source ↗
“Come to find out he installed a 2 stage non-communicating compressor with a 2 stage econet air handler. It came with an econet thermostat that he swapped for a Honeywell. So I paid for a 2 stage and I have no variable air and no humidity control.”source ↗
“Unfortunately I'm out of alot of money and didn't get what I wanted. I could have saved about $5k and just got a 1 stage😔”source ↗
Where this came up
People with this problem also raised
- 14Why does my brand new AC not cool as well as the old one?
- 7Mini-split can't keep house warm when it freezes outside
- 3Thermostat wiring for separate PTAC cooling and hydronic boiler heat
- 3Refrigerator stops cooling properly after being moved on its side
- 4New HVAC unit won't heat and makes clicking sounds
- 4Furnace lights up briefly then hums and shuts off