HVAC tech's out there?

[EarPlug]

See page 14 of the installation manual

FOR CONSTANT OPERATION: Press the fan icon
until the 100% light is on. The “Runtime %” light turns
on. The ERV unit will run continuously

http://www.munchsupply.com/docs/default-source/trane/energy-recovery-ventilator-(erv)-install-manual.pdf?sfvrsn=0

 

[Paddy]

Earplug,

Our unit was wired for remote operation via fancy T-stat. We do not have the PT or the PB as shown.

 

[dadster4]

Terminals 1 & 4 are the common of each of the two poles, so 1-2 and 4-5 are NC (normally closed), 1-3 and 4-6 are NO (normally open), when power is supplied to the coil (two inner unmarked terminals)1-2 and 4-5 will open and 1-3 and 4-6 will close.
With knowing how the relay works...try to figure out what supplies 24v to the coil, and what circuit the switched terminals are affecting...let us know

 

[Paddy]

Dadster4,

That was helpful. I think I found the solution. Terminals 2 and 5 have 24 VAC. If I jumper 2 and 5 to the unmarked terminals, (connected pairs), I should have the 24 VAC where I put my switch

 

[dadster4]

Terminals 2 an 5 may very well be on two different circuits, and cause other issues if connected in any way. What is supplying power to the coil terminals on the relay?

 

[Paddy]

Dadster,

I was assuming the 2 pole switching relay had a built in 24 VAC power source. Sure looks that way on the schematic. But might have been a seperate 24 VAC power source that was removed when it was installed connected to the HVAC system. I'm leaning this way because in the schematic it shows the 120 VAC common going to the transformer. But I see it wire nutted direct to the fan motor.

So most likely, I will buy a 24/120 transformer and be set.