OT any HVAC guys on here? Options

[seanery]

My A/C needs a recharge. I bought some refrigerant a couple years ago when my uncle was up here visiting. He had his gauges and refilled the system. I watched him do it, and remember a bit, but not all.

Can anyone give me a brief how to?

this is a home, not a car system by the way.

thanks in advance

[Joe.D]

Actually, I think its now illegal to use freon without proper recovery equipment. The very high price, and the very limited availability reflects the intent to discourage its use.

But, if you have some, and the right tools, and intend to try to charge the system yourself, you should first make sure the system has no leaks so what you put into the system stays in the system

You probably have a 2 manifold gauge set - one for a "high" and one for a "low" range of pressure.

The high side reading is used to monitor the pressure after the compressor.

Connect these to the ports near or on top of the compressor. Then, use a vacuum pump to evacuate the system through the low side.

You fill the system by bleeding freon gas, NOT LIQUID into the low side as the compressor is running. Keep the hose from the supply bottle on the top, to be sure you don't introdduce liquid freon into the compressor.

Low side pressure should be around 35, high side around 150, and will cycle up and down as the compressor kicks in and out.

There is usually a sight glass somewhere in the system (often on top of the reciever/dryer). As you fill the systems you will see cloudy white flow across the sight glass. When you don't see white flowing across the glass anymore, the system is full enough.

I'm not an HVAC engineer, but I have done this quite a few times over the years. Even so, I'd get a professional to do it. And offer to trade whatever is left from the bottle of Freon as payment for the service call. :-)

Joe