Hi,

I have a Burnham Series 2 Gas Boiler that until recently had only 1 zone (supplemental heat for a sunroom) and it worked fine. I added in a new zone for my basement and a new Honeywell V8043F zone valve (exact same as existing valve) and cannot get the boiler to fire - only the circulator comes on. Here is how I wired in the new valve and new thermostat:

New Zone 2 Thermostat (Honeywell RTH 6450):
'R' to 'TH-TR' on Zone Valve 2
'W' to 'TH' on Zone Valve 2

Zone Valve 2:
'TR' to 'TR' on Valve 1
'TH' to 'Zone 2 Thermostat'
'TH-TR' to 'TH-TR' on Valve 1
'End Switch' to 'End Switch' on Valve 1

Zone Valve 1:
'TR' to 24v External Transformer
'TH-TR' to 24v External Transformer & to 'Zone 1 Thermo' (R lead)
'TH' to 'Zone 1 Thermo' (W lead)
'End Switch' to Boiler 'R' & 'G'

So, I am running the 2 zone valves' wiring in parallel - do I need to separate them?
Also, when I first connected the Zone 2 valve, I switched the 'TR' and 'TH-TR' wires accidentally (I rushed thru it and didn't check my work!!) and then realized it - did I damage something?

Thanks for your help!

-Mark

 

I think you've got it wired properly...

No, I don't think so, the transformer is AC and polarity shouldn't matter.

This is with BOTH zone valves, correct?

 

correct - when either thermo calls for heat the boiler doesn't fire - just circulator comes on. I think the zone 1 valve is opening when thermo 1 is calling for heat but I'm not sure about zone 2 valve when thermo 2 calls for heat.

 

Are you trying to use the transformer in the boiler to operate the zone valves?

Or is the zone valve transformer separate and external to the boiler?

 

It's an external 24v transformer that was present when I only ran 1 zone valve.

 

OK, that's good... don't want to overload the transformer in the boiler.

Here's what you can do to determine if the boiler itself is having a problem:

Turn power off to boiler.

Disconnect the zone valve endswitch wires from the R and G terminals in the boiler.

Place a wire JUMPER between the R and G terminals and turn power to boiler back on.

Circ pump should run and boiler should fire.

If not, then something going on with boiler.

 

Well, before I followed your advice, I decided to re-check my wiring and reattach the leads and everything is now working fine. The boiler fired right up with either thermo calling for heat. Not sure what the issue was exactly. I bled most of the air from my system and it's pretty quiet at the moment. I had to deal with an ornery auto-bleed valve but it finally let the air escape. Any advice on keeping this freed-up?

Thanks for your quick feedback NJ! It is appreciated! -M

 

The boiler water wasn't HOT at the time, was it? If boiler temp is above the limit setting the burner won't fire... maybe it was that?

What is the boiler temp setting on the aquastat?

What type of auto-bleed do you have?

Usually not much to do with those except replace. Some can be cleaned. Problem is usually mineral build up that precipitates out of the water.

 

The water temp was prob around 115-120 at the time - the kick-out limit is set for 165. I think the temp was low enough to be firing the boiler but maybe I brain-farted at the time.

I think the auto-bleed is a Hy-Vent product. I keep the cap fairly loose on it and I think the air interacts with the minerals (like you said) and gums it up. I just wiggled a small screwdriver in there and it seemed to open up OK. When you replace those, do you just drop the pressure in the system and quickly swap out the old with a new one? I would think that would keep you from having to bleed the system again. Thoughts?

 

Yes, you can... small hole, no pressure, have ready new one at hand.

I just watched a video where a guy replaced a lower heating element in an electric 40 gallon hot water tank without first draining it... dude was QUICK! only lost about 2 gallons! ha ha ha ...

Maid-o-mist has a thing they call the 'Shortstop' model 9AS. It's a little gadget that goes between the auto-vent and the system which has a spring loaded stopper on it. When you unscrew the vent, the stopper closes. You still need to drop pressure, but don't need to work as fast.

 

Thanks again - I will look into the 'Shortstop' product when I replace the auto-vent.

Sounds like the guy replacing the heating element was winning a bet!

 

Shortstop is cheap too... under $5

9AS - Jacobus - Maid O Mist 9AS - #9AS Shortstop Automatic Shutoff Valve

You don't really NEED this thingy though... It's really not difficult to change one quickly... and either way, the pressure needs to be dropped...

One thing I'm not 100% certain of though is whether it will work properly with other brands of vents. The Maid-O-Mist #67 has a little extension out the bottom that will push the thingy open. Not sure if the others have this as well? (Taco, etc)

MO67 - Jacobus - Maid O Mist MO67 - #67, 1/8" Auto-Vent

 

With all the black crap that came out of the tank, one should wonder why he wouldn't want to flush the thing out ANYWAY!

The fun begins at 6:30 if you wanna skip ahead. Actually I don't even think he lost a quart!

By the way, disposable diapers are better than towels for this. Every plumber should have a box on his truck! Ya just never know when you'll need them!

https://www.youtube.com/watch?v=MyC55h7lhYM

:bad poster: