Hi! I hate HVAC!LOL
Went on a roof top unit today and it was a DC system.
Somebody most of been there previously because there was only a white,yellow and brown wire connected to the control and the fan was running all the time. So I did not really notice this till later. So I put my gauges on and pressed the contactor in and the CFM came on and the compressor. The low side pressure dopped to like 10 psi and the high side raised a little. I think it is a stuck closed TXV. Or blocked liquid line?? Has to be a TXV issue? Any ideas?
Lucky they had 2 units. So I put the rest of the t-stat wires back like the other unit ans still nothing. No error code or anything. Is there a website or something on how to troubleshoot DC circuits on rooftops? It had on the schematic some weird wordage where the t-stat wires belong.
It was a TRANE
Please if you have any suggestions!
I never came across DC systems to much.