There is no 24v in the low voltage line at the outside compressor that is needed to connect to the contactor. The A/C is set on the thermostat inside and the blower comes on and runs but the compressor does not since there is no 24v signal at the compressor. I cannot see where the low voltage line running to the outside compressor is connected to the controls at the furnace. I am still looking for that connection so I can tell if the lack of 24v is due to no signal from the control or if the long low voltage line is broken somewhere. I have a very lightly used Lennox G20-E unit that is a 1992 model that is in good condition otherwise. This problem just surfaced last week. Any ideas where I should determine why the missing on the 24v low voltage line? I measure the BCC thermocouple voltage of R to Y as 5v. Also the R to Ground is 26v and the Y to Ground is 20v taken with the blower running.
"R" is routed to the thermostat and then the thermostat sends the voltage back to the "Y" terminal upon a call for cooling.
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