Hi everyone,

I hooked up a Lux stat from Ace. Three position switch - heat/off/cool. Two position fan switch - auto/on.

Caped the blue in the unit going to the -24V side of the condenser contactor in the unit.

Jumped the RH RC terminals for a single transformer.

The heat works great in the fan switch auto position - pre-fan comes on lights and blower kicks in, all on auto - great.

Problem: In the fan auto position - Neither the fan or the condenser will come on. I have to put the fan switch in the "On" position for the compressor to come on. It will then cool and shut off the condenser, but the fan keeps running and will not shut off.

Is it perhaps the T-stat?

Any advice welcome, thanks in advance.

Power Tech

,, (quote),, Caped the blue in the unit going to the -24V side of the condenser contactor in the unit.

Not sure I understand,, you said you capped the blue wire going to the contactor,, are you say you now only have one wire connected to the condenser contactor? if so this want work you need 2 wire,, hot going out and a 2nd (common coming back in

,,,(quote) ,,,,,Caped the blue in the unit going to the -24V side of the condenser contactor in the unit.

not sure I understand,,,you said you capped the blue wire going to the contactor,,,,are you say you now only have one wire connected to the condenser contactor? ,if so this want work you need 2 wire,,,hot going out and a 2nd (common coming back in

Common LV already connected to xfmr direct. Factory recommends capping in unit. Hot for contactor comes from comes from harness on circuit board.