Howdy.. Last night my zone valve started knocking constantly while in the closed position and the circulating pump is running.. When the valve is open, or the circulating pump is off (no zones calling for heat) then it stops. But as soon as the pump kicks in, it starts knocking again.. The knocking is heard through-out the baseboard heating in the zone, which is downstairs and is loudest and pretty annoying down there.... At the boiler, the knocking is just a loud ticking, but amplify's through the copper piping when downstairs.. I don't believe this to be an air issue as it is constant and only when valve is supposed to be closed and the pump is running.. No knocking when valve opens or lines heating up.. To further my frustration.. It now seems like the valve may be partially stuck open, as the heat down stairs is showing 78 degrees while the thermostat is set to 70. The thermostat is and sylinoid are working, as I can see and hear the valve work when I had my wife turn it up to 82 degrees, and watched it operate (supposedly close) when she turned it down!! Not sure what the problem is, or what my options are... Any help is much appreciated.

 

Not an expert but I had a similar problem with one zone that had an older analog mercury switch thermostat. It would cause the taco valve to click on and off rapidly as the mercury tube tipped and bounced. If you have an analog thermo, replace it with a new digital. Or better yet, wait for someone who knows what they're talking about to answer.

 

Thanks toolmon...I replaced the thermostats a few months ago.. got some fancy digital ones hooked up to a z-wave controller.. pretty neat stuff... Got them set up on a programmer to adjust up and down depending on the time of day and day of week.. can also access thermostats and adjust from my phone!! technology.. gotta love it!! I don't know much about zone valves.. but this seams to be a diaphram or gate issue of some kind.. wondering if it is replacable and how difficult it'd be.. It is a White-Rodgers Type No. 13A03-112 Zone valve.

 

I can't think of a reason why a zone valve would 'knock'. Something isn't making sense here.

Let's check a few other things first, maybe there's something else going on that's causing this.

When the boiler is HOT, read the temperature/pressure gauge and report what you see.

In this thread:

http://www.doityourself.com/forum/bo...sion-tank.html

are step by step instructions for checking and charging your expansion tank air pressure (presuming you have that type of expansion tank, let us know if different).

Run the step by step and report what you learn.


I suspect that the W-R valves are similar in design to the Honeywell. The Honeywell valve have a composite 'ball' inside that is 'pushed' in front of the pipe opening. It's a very simple design that rarely causes problems (not so for the power heads though!), the valve body itself is remarkably trouble free.

Your particular valve has been obsoleted, here is a cross ref to same manufacturer:

http://www.emersonclimate.com/en-us/..._06_pg0135.pdf

If it turns out that the problem is not elsewhere and you do need to replace the valve, you don't need to replace with W-R. You can use Honeywell, Erie, Taco... whatever you choose. Might have to change a little wiring, but that's pretty easy. We can help with that if you need it.

Just found this:

http://s3.pexsupply.com/manuals/1264..._PROD_FILE.pdf

I doubt that all these parts are still available, but the pictures give some insight into what's inside the valve. Looks like these are not the ball type, there's a disk inside that apparently gets pushed down onto a seat.

The part list says there is a 'spring' in the disk kit... I wonder what happens if that spring bites the big one? Maybe the disk rattles and knocks?

Whattaya know? AMAZON has that kit... pricey though! and you will also need the other seals and things I believe.

Amazon.com: White Rodgers F84-1215 Valve Assembly For 13A01: Home Improvement

Seems that Pex Supply may have the parts also:

F65-0439 - White Rodgers F65-0439 - Body Seal Ring For 13A00 Zone Valves
F84-1215 - White Rodgers F84-1215 - Valve Assembly for 13A01

If I were replacing, I would use a valve that is easy to obtain, such as the Honeywell V8043 series.

 

Mr. Trooper... Thank you so much for the info.. The temp is reading a little better than 175 and the pressure at about 23 psi. I just had the boiler serviced a couple months ago due to the leaking pressure relief valve, the repair dude changed the expansion tank and circulating pump. Sure wish I read that thread before, seems like things I can do myself!! It is now into the winter here in alaska with sub zero temps, so I am hesitant to shut my boiler off in fear that I might screw something up in my repair process.. Summer time isn't that big a deal!
The diagram of the valve with the spring and disk sure leans me toward believing that the spring may be toast.. The sound coming from it would seem like the disk slapping down over and over like it's not staying seated... It's not a loud noise at the boiler, but downstairs is sound like the lines are hammering.. pretty loud.. I am fairly convinced it is isolated to that valve and not an air or pressure issue as I have three other zones that are working properly!! The price for the kit is not too bad, considering a replacment valve will cost easily twice that! I will order it and install, and will post result! There is a valve top and bottom of the zone valve, so I should be able to isolate it and re-build without having to shut down the boiler? Man, your help is much appreciated!

 

Alright.. It was the spring in the valve assembly.. broke in pieces!! Was able to find that vavle kit in town locally for under $20. Smoking deal! Although the sales rep didn't have anything good to say about that type of zone valve!! Wondering if individual circulating pumps might be a better route than zone valves as I'll probably change the valves out come summer....?

Once again, I thank you very much for your help with this and the time taken to provide that help.. Happy Holidays!

 

If you go with individual pumps you will still need something to stop the flow to other areas inthe house such as a zone valve or flow controls

 

Out of 3-zone valve, one valve stays open after the operation. Circulator and boiler stops once temprature in that zone reaches the set value. However, when other zone demands heat, the hot water circulates in both zone. What I noticed is that valve does not go back fully. Few times I pushed it back by pressing the one of the notch where spring is attached under the motor head. That works all the time. I see both springs are in place. I suspect may be they lost the strength when they were new (many years ago). Boiler service man told to change motor head, but I am not sure if that is the right suggestion. Anyone has any idea what could be reason and how to correct/fix it?

Attached Pics shows the two springs and the notch where spring is attached is also marked with white spot. This spot when match with a white spot on motor head, indicats valve is in close position. When it stays stuck open, this notch does not come back to return position and both spring remains extended until pushed back. Some time push back requires lots of force.

Thanks,
-Shal