Hey guys got a new house I just bought it has 3 zoned heat I'm having a problem with my zone 2, it will only fire on when my zone one is on and I know why I just need some help with wiring,but I beleive the call switch to turn the oil furnace on when the thermostat is turned on isn't connected, terminal 3 that is I would like to be able to shut down and turn all zones on independently and it looks as if zone 1 and 2 are daisy chained together I just need to know what wire to attach to the third post on zone 2 to make it function by itself. Thanks a lot

 

Cb,
#3 terminal is the one that turns on the burner.
#1 & #2 open when the tstat calls for heat and then make and end switch and powers #2 & #3 which turns on the burner. #2 is a common terminal to both the t-stat and the boiler.
#2 & #3 will go to the same place the others are connected to.

It looks like you have a red wire that's not connected. Trace that and see if it goes to the boiler.

Good Luck,

 

Ok great I will check tonight. If it goes to the boiler than just run it off post 3?

 

Cb,
Yes , but check it first and make sure it goes to the boiler or where the others go.
They might have removed it for a reason so double check it.
They haven't made that valve in green in probably 20 years. It may be defective.
If so you'll have to replace just the head. You don't have to replace the whole valve since you know it works as long as one of the others call.

 

So I got it all straightened out tn. It was actually the white wires that were on all 3 zone end switches. The wire actually broke off the terminal. So stripped the wire reconnected it, and the zone fired right up. The only thing that threw me off was the fact that a red was daisy chained in, but upon further inspection that red just takes all three endswitches to the box on the front if the furnace that has the TT in it. Im pretty confident this is correct, I tested all 3 zones working prpperly, and being a mechanic I'm very comfortable with electricity, al be it ac voltage is a whole new ball game to me as opposed to a cars dc voltage, concepts are the same I beleive. Any ways I'm going to redo this wiring and thanks to spott I'm going to replace those two green power heads bein as old as they are. Thanks again spott! Saved me a ton of money this winter in pa has not been kind to my new house! Here's a pic of my fix.

 

Cab,
Personally I'm not a big fan of daisychaining these things but electricians due it to save wire or something.
The other thing is that you mentioned AC voltage. Although you boiler system is 110v the zone valves are 24v connecting into the TT on the aquastat.
Glad it's running.

Be Well,

 

24v?? Interesting they must use some kind of step down capacitor?

 

Cb,
Following the wiring to the zone valves you will find a 24v transformer to begin the circuit. It is a series circuit.
It starts at the transformer.
From transformer > t-stat
T-stat > #1 on zone valve
#2 on zv > other wire on transformer
That circuit will open the zv on a call for heat from the t-stat and make the end switch
#2 & #3 on zv > TT on aquastat.
This circuit will turn on the boiler on a call for heat
The t-stat calls for heat and activates #1 & #2 to open zv, which makes 2 & #3 to turn on the boiler.
The zv's are a 24v circuit up to the TT in the aquastat, then it goes to 110v to operate the pump and
burner.

In regards to changing the green zv's. They are old but if they're working I would leave them until they fail. You can always just put them on manual to get heat when any other zone calls until you get a new one.
I've had green ones in my house since 1984 and are still working.
Having a spare won't hurt but I wouldn't waste the money replacing them until they fail.