Hello,

We had our HVAC system installed by people that are no longer available for comment, yes I did get a bad deal and trying to fix it now.

So basically right now there are 2 Zones from 1 unit. The 1st (main) zone has the stat on it and seems to be working and actually on the 2nd zone a feel a bit of air coming from the vents but it`s very little. The 2nd zone has 3 wires with out the stat connected to it right now. This brings me to my question.

The 3 wires are Red, White and Blue. I tried red and White since there is no Blue terminal and I get nothing... The stat does not power on(nothing on the screen no power at all). I also tried with a battery Stat, but it does bring more air in. Not sure what else do to. If anyone can help it would be great !

Open the damper manually

I would like to use a thermostat there, that's the whole point... I`m just not understanding how to connect it to make it work...

If it is a 3 wire it must have a common wire then a power open and a power close. How is the one for down stairs wired??

I have to take a look. But there are at least 5 wires down stairs. I think the white wire is common does that make sense ? Based on my reading the Red should be power ? I have few different stats I can try most are honeywell... Should I take a look at the Damper how its wired ? Would Blue usually go to Y ? This is bad I wish they would have finished the job at least up to this point... They were also supposed to install a fresh air exchange which I have no idea what it looks like or what to look for...

Some dampers are normally open, some normally closed. If you have no voltage you need to see if the control board is sending a signal. Since 1 is working, I would guess you have a wire disconnect. Some dampers only need a 2 wire, the power opens the damper and a spring closes or vice versa.

But I might be putting in the wrong lead ? Are you saying the damper doesn't have power ?

What I think I need to understand where does the second stat gets power from? Is it the dampers transformer ? I guess I have to go up to the attic and see where where are the wires coming from...

The issue is I`m not even living in the house now and trying to get in here... If we have to move now its so hot its just crazy...

The t-stat goes to a main control board not the damper. Is the main control even wired for 2 dampers? take of cover and see how many sets of wires are in there.

do you have 3 dampers? You should have a zone 1 damper, a zone 2 damper. And a bypass damper from the supply to the return in the basement. A fresh air intake should be a box about 2x2 with 3 ducts going into it. Or it could be just a small pipe taken to the outside if it was done the cheep way

So is the unit that flips the damper ? Why is the T-Stat only has 3 wires (second t-stat for subzone) ?

What brand damper system is it?

do you have 3 dampers? You should have a zone 1 damper, a zone 2 damper. and a bypass damper from the supply to the return in the basement. a fresh air intake should be a box about 2x2 with 3 ducts going into it. Or it could be just a small pipe taken to the outside if it was done the cheep way

I`ll check in the attic. What I saw in the basement is a big intake that is sucking the air from outside in which is joined by the return ducts in the back of the unit.

This is for my other zone. So I guess to make it clear I have 3 zones. 2 Units.

1st Zone is for first floor and basement, all separate units. T-Stat works, cold air seems to be good. I did not test the forced hot air yet.

2nd Zone is the second floor separate units in the attic T-Stat works

3rd Zone is shared from the second zone from the attic and is 3rd floor. No T-Stat installed just 3 wires Blue, Red and White


All zones were supposed to have fresh air exchange.

what brand damper system is it??

I have to climb in the attic and check. I guess I`ll get all this info tomorrow. As I said we could not move in yet. So I have to go by the house and write all this info down, trace the wires etc...

I checked today could not find the actual damper, what is it supposed to look like ? I think after playing with the leads with battery powered t-stat I think the air is moving better now, but still no control from the 3rd zone t-stat. I guess I have to bite the bullet and call new repair men and hope that warranty will stay on the units when and/if this guys are able to fix it.

So today I looked and I see the 3rd zone wires are NOT connected. So does that mean a damper is not installed ? Also found another HUGE issue. There is a water build up, and I mean a lot of water in the duck insulation where the duct starts from the unit... It was so much water that I have to redo the sealing below. And I don't understand where the water is coming from condensation ?

Could be, or if dampers not working, or no bypass damper was installed unit may be freezing up

Seems only on that space right when the duct starts... I don't think I can get away with out calling people in... Thanks for the help guys...