Lennox GCS24-953-...............

[toxic11]

Dose any of you gents know how to troubleshoot the economizer in this model of lennox rtu.

Let me tell you what I did. I put a jumper of the T and T1 on the A6 module. Than I jumped the fan. And turned the unit on. I turned the potentiometer to 100% and nothing happened. Put on the actuator there is a connection T1 and T and when I put T1 cable to T and the T cable to T1 the acuator moves. So I know that the issue is either the outdoor enthalpy sensor or the A6 logic module. But I dont know how to test either of them

[Octopus]

The older lennox units I work on have a enthalpy sensor and theres a ckt bd with two pots on it. I remember the unit would show the y1 y2 LED's lit but no compressors would run, you could turn one of the pots and the stages would run and either the ckt bd was bad or the sensor. Theres specifics in the IOM.

I also remember some units did not have a enthalpy sensor but the ckt bd controlled the economizer by out door temp, ER something like that it is in the book.

It's been too long since I have messed with them I'm forgetting stuff already!