HVAC w/ Heat Pump Including All-In-One Air Handler No Control Board No Distinguishable Common

I have about a 3-year-old unit and believe it is an all-in-one HVAC with Heat Pump and everything including the air handler is built into the outside unit, no furnace (typical in FL mobile homes). Somewhat [like this](https://www.alpinehomeai


There doesn’t seem to be a control board or a distinguishable common on this system that I can find. I see a couple Blues but want to make sure.

As a result, I am at a loss as to what to do with the C wire exiting the adaptor (or, ideally, if I can manage to do away with the adapter altogether, utilizing the extra open leads, and still keep the independent fan control).

I’ve seen a lot of situations that @speadie and many others have settled but I can’t find one exactly like mine (I apologize if I’ve overlooked it).

All Images:

I had 4 wires, and a jumper on RH at my original Thermostat - https://photos.app.goo.gl/X15CzmhfSg9gFE8y9

W, RC, G, Y (with the removed jumper) https://photos.app.goo.gl/rGtCqvjEb4bRQjhr9

There other unconnected leads, therefore if possible, it would be beneficial if a blue or others could be utilized instead of the c-adapter. Clearly the 4 wires from the thermostat connect to the same color-coded wires at the unit side at least - https://photos.app.goo.gl/uqS7Nn6Zgjgkt1FR6

I would be very grateful for any assistance. More images can be made available quickly if needed.

First and foremost, make sure there is no power running to your package unit - the voltages inside there can be deadly.

Check the wall behind your current thermostat for the blue wire, some installers will cut it off short, but most will just tuck unused wires into the wall cavity. If you’ve got a blue wire in your wall, then you wont need the C adapter,

Either way, you will need a wire with a quick disconnect female connector on it. For some reason, someone cut off your old C wire in your package unit.

If you take that cut wire off and get another longer wire with that same size connector on it, and connect it to that terminal on the contactor, that will be your new C wire in your package unit.

If you found a blue wire in your wall behind your current thermostat, then you can connect the blue thermostat wire that is wrapped around the thermostat cable in your package unit to the new C wire, otherwise you will need to connect the grey C wire from the C adapter to the new C wire.

Thank you. I’ll be trying this tomorrow. All the wires are tucked right behind the wall at the thermostat.

I still get a tick in the thermostat, without power. Should the blue at the thermostat side be connected to the C terminal on the thermostat c-panel?

Edit: since there was only a single male terminal with a double female terminal attached, I was able to get a good connection bringing the blue wire straight over with a small butt connector Simply to test. If that’s correct, then I will probably pull it back off and redo it or solder it, and use a heat shrink tube for it if needed. Pretty tight right now.

The lower one you have crimped on is a piggyback terminal, it has both a male and female connector

It should work the way you have it hooked up, unless there is a disconnect in the blue wire somewhere in between the package unit and the thermostat but I would recommend using a proper connector with a wire nut to connect it to the thermostat wire , and route the wire around the contactor, not over the top of it. The contactor’s contacts are exposed high voltage, only the coil is running off of 24V.

If it only clicks when you attempt to power it up, then your blue wire is probably not a continuous run, if this is the case, you can either follow the thermostat wire to see where it is spliced, or use the C adaptor.