Any HVAC experts?

[Seriak]

Well no luck. No matter if the thermostat is set to off, hot or cold as soon as I turn on the air exchanger, the outside a/c fan comes on. Now to decide whether I bite the bullet and pay an arm and a leg to fix it now (As you know they will overcharge me somehow) or just turn off the A/C in winter.

[rayjay]

You should be able to trace the wiring from the AC and from the air exchanger to where they interconnect and fix the problem there.

[e46er]

Originally Posted by Seriak

As you know they will overcharge me somehow

call a reputable company then because not all heating and AC companies are crooks

my companies AC service call is $135 and $95 an hour after

if you dont wanna pay a company your going to have to learn to do it yourself

[wingedfish]

You won't fix it yourself unless you can understand what everything does. Before you had the AC installed the HRV was interconnected to your furnace/airhandler fan. The a/c guys tied into this same system. When your tstat calls for a/c, an inter connection in the tstat brings the air handler fan on also. What is happening to you is it is back feeding so when you turn on the HRV, the a/c turns on as well. This is very bad. To verify if i'm right, turn on your hrv and if the a/c is on, flip the fan switch on the tstat to "on". The a/c should turn off. At best it will cost a boat load of power. At worst it will ruin the compressor. Let the a/c guys know and they will likely fix it up for you.