EWC Controls Forum

Hi,

I have a 2 zone gas furnace that is controlled by a EWC ST 2D control panel. From the last 3-4 days, there is absolutely
no airflow to zone 2, while zone one 1 is working fine. There is considerable whistling from zone 1 as I am guessing it is air
pressure that needs to be relieved.

Could the damper be an issue - here are the details:

Cannot find model number..blue box has label "Motorised opposed blade damper"

Wiring... White (4) Orange (5) Red (6) Z
Green (1) Orange (2) - Jumper from 5 above

Please advise how this can be resolved...

Thanks

It sounds like there could possibly be an issue with the damper.
If you look at the back of the motor where the linkage arm is are you able to see a small illustrated sticker that shows the open and closed position of the arm?
If so, based on that illustration can you tell if the damper blades are open or closed?
I will attach a picture of this illustration.
You want to check the position of the arm when that zone should be in the closed position.
In other words, check when zone 2 is off and zone 1 is calling for heat.
Based on the position of the linkage arm we might need to troubleshoot further with a voltmeter if you have access to one.

_________________
Patrick Cyrana
Pcyrana@ewccontrols.com
1-800-446-3110

Patrick,

Thanks for your response and the picture.

The zone 2 damper was about 85% closed and after a few taps it has moved to the open position
as laid out in your picture.

Based on your suggestion, I shut off heat to zone 2 and turned up the heat for zone 1. The damper
has not shut off for zone 2 (there is a clicking sound from within the duct). As a result there is distributed
air flow across both zones, even though, zone 2 is not requesting heat.

Thanks

Sayeem

First thing I would have thought to do is replace the filter, but good call with the damper.

OK, now would be the time to check voltage at the motor itself.
You would want to check between the M1 and M6 terminals on the motor to see if it has voltage telling it to close.

_________________
Patrick Cyrana
Pcyrana@ewccontrols.com
1-800-446-3110