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rabooze · Mar 13, 2006, 09:17 AM

I installed a Hunter Auto Saver 550 in my home recently. Everything seemed to be working fine as the heat worked and that has been all I needed. Now that it has warmed up here and I need AC, the unit does not respond. I set it on cool and nothing happens. Even when I move the fan switch to "On" instead of Auto, it does not respond. Any ideas for help here? I made sure that I moved the switch on the internal part of the unit to the "O" setting because I have an orange wire.

labman · Mar 13, 2006, 09:32 AM

If your system is a heat pump, it needs 2 signals to provide A/C. The orange wire usually runs to the reversing valves. You also need a signal, usually using a yellow wire, from the Y terminal to the air handler and outside compressor to start them up. Check those connections.

forestoney · Mar 25, 2007, 08:45 PM

I have a twist on this same problem. Same thermostat unit, and same issue (controls heat, but AC won't switch on now that the seasons have changed). But, I don't have an orange wire. Seems like it's a typical 5 wire setup. Gas heat and elect AC.

Anyone have advice? It's starting to get pretty warm here in Texas...

labman · Mar 26, 2007, 04:19 AM

Check the sticky at the top of the forum. Last fall we had a great new member show up. Northern Heat was quickly appointed H&AC expert, and set up what I think is the best sticky on AMHD. If you don't find your answers there, post back.

forestoney · Mar 26, 2007, 07:03 AM

Thanks for the tip. Unfortunately, there isn't anything in the sticky that speaks to my issue.

The furnace worked flawlessly, however the AC refuses to function at all. I originally replaced our old thermostat (the Honeywell installed when the home was built) because it threw out a "bAt lo" error and then freaked out (random flashing on the LCD). I replaced the batteries, however this didn't fix the issue so I replaced the thermostat (I should note, I tried re-installing the old thermostat, and it worked briefly then threw out the same bAt lo error and the LCD freaked out; again, the batteries were new).

All was good until I needed to run the AC. Again, it ran briefly when the old thermostat was re-intalled, but doesn't even respond when the Hunter Auto Saver 550 is up.