Taco Zone valve/head issues

WhirlingD

Hi everyone…

I have a roughly 20 year old oil boiler system feeding forced hot water baseboards… With one circulator pump and four Taco zone valves…

Last winter, I ended up having to replace three of the four, diagnosing them through swapping them around and a process of elimination… After that, it worked fine all winter… Until yesterday, I find one zone not working.

So, I swapped the zone heads of one working zone to the one that wasn’t (leaving the wires intact), and the non-working zone worked fine with the working head, but the previously working zone no longer worked with the potentially nonworking head. Hopefully, you get the drift.

Is this a satisfactory test to determine that it is only the head that needs replacement? Are there any other things I should be considering before plunking down 100 bucks for a new valve head?

Is there a workaround with somehow freeing up a stuck plunger inside of these things?

Sadly, I didn’t put a system in place that told me which ones I replaced last year, so I can only presume this is the one that I didn’t replace last year… But no way to really know.

Granted, I had 17 years in this house before I had to replace a zone head, but it seemed very strange that all three went out upon first start up of the system just over a year ago.

Thoughts?

EdTheHeaterMan

The temporary work around is to open the valve manually using the lever that is next to the 3 wire terminals. When that lever is down the valve will stay open. There should be a date code on the bottom of the valve actuator. See if the defective one has a different date code.

WhirlingD

Thanks for the date tip. I will look for that.

Thankfully, the weather has been warmer in the Northeast, and I am finding that the room that the zone heats, which has a little use, can actually pick up a little bit of residual heat from the main part of the house.

I was figuring that if the weather gets colder, I can just put it in manual mode, but it won’t be hugely efficient, given that there will be hot water going through there every time the circulator kicks on.

hot_rod

A Taco Gold Top? Is there a rebuild kit for the bottom valve part? If the pin gets too hard to activate I suspect the powerheads will suffer.
May be cheaper to buy a whole new valve and swap top and bottom guts.

There are some press type valves to make a quick easy swap out.

WhirlingD

EdTheHeaterMan said:

There should be a date code on the bottom of the valve actuator. See if the defective one has a different date code.

I took the thing off and looked on every side and didn’t see a date code. It’s one of the 555 series.

Joe Mattiello

I believe the date code is on the lever.
the head has a 3 year warranty. You can call tech support at 401-942-8000 and ask for tech support. Have you ruled out thermostat issue? You can validate a demand by tying your thermostat wires together. 

WhirlingD

Joe Mattiello said:

Have you ruled out thermostat issue? You can validate a demand by tying your thermostat wires together. 

Thanks for the tip, Joe. I’ll check the lever.

Yes, I swapped out thermostat heads, since they just pop on and off. I took one head that I knew was working, and put it on the station that wasn’t. The zone still didn’t work.

To validate it wasn’t the thermostat base, I flip-flopped two zone valve heads, and the head from the working zone allowed the nonworking zone to operate correctly. Plus, the suspected nonworking head did not work in the zone that usually works… Not sure if that made any sense… :-)