Zone valve failure

Gardyloo

Recently had to replace two Honeywell zone valves V8043E 3/4" and 1".
These were installed 6 years ago.
Oil fired low mass boiler (EK System 2000). Closed system with two zones, one for a buffer tank and one for a unit heater.

Water was treated with 8 way, which had turned black as it was depleted.

These are good valves and never had issues with them in the past, have some on jobs for 30 years.

Spoke to Honeywell and waiting for a reply. I replaced the valves but would like to know what happened? I would appreciate any feedback.

(I dont know if this is the best sub-forum to post this, if not please let me know)

EDIT, attached pics correctly.....

Alan (California Radiant) Forbes

Unusual - I’ve never seen that. 

Are the zone valves oriented properly?

What pump is on the system?

HomerJSmith

...which had turned black as it was depleted...

I don't understand what you are trying to express.
How about a pic of the actuator with the round ball.
It looks like de-zinctification. Maybe an acid fluid?

kcopp

Why did you put 8 way into the system?
Did you leave it in and how much?

HomerJSmith

In this valve the round ball is spring loaded to push against the flow (toward the incoming water). If the pump is too great a pressure because it is not properly sized, then, the flow could push the ball stopper slightly open allowing a flow thru the valve and over time erode the brass housing.
Again-What size pump do you have pushing water thru these zones?

hot_rod

The metal erosion could be a combination of velocity and aggressive treatment, what is the ph of the fluid now? How does the rubber ball look. Aggressive fluid can attack that component

This doesn’t look like a material failure, the fault of the valve

Roger

Thank you for your post, @Gardyloo .

You mention a buffer tank, do you have radiant tubing? It’s possible that that has deteriorated (black water) and no longer has an oxygen barrier. 8-Way has an oxygen scavenger and elevates the pH so there’s no corrosion, however non-oxygen barrier tubing and/or make up water can deplete and prevent proper long-term water conditions.
That boiler has 007 and a bypass, so there should be no problem with the head pressure on the zone valves.

Thank you,

Roger

Gardyloo

Yes, buffer tank is for radiant heat, all tubing has O2 barrier (Wirsbo).

Pump is a 007 Taco, supplied by the boiler manufacture and oriented the correct way (supply side).
Realistically these are "circulators" not pumps, meaning minimal pressure and really relies on system pressure to pump.
Zone valves oriented correctly.
When zone valves are closed the boiler pumps through the plate exchanger to keep the water flowing and prevent hot spots.






8 way is always in the system and should be maintained at level that is violet colored to maintain protection, it was very dark green, it was almost black, meaning it had lost its potency.

Make up water is generally left off and only opened if system is low, maybe twice a year, because it is a high mass on demand system the pressure can fluctuate, estimated volume ~ 70 gallons.

I am perplexed and plumbers I trust are as well, they all like the 8043's and I dont think they are at fault.

My discussions with others have convinced me that water is escaping around the ball and "scoured" the valve body. I have attached a picture of the ball and if you look close you can see the wear that has taken place on the actuator arm, when installed in the valve body this would line up with one of the scours in the valve body.

Furthermore, once I replaced the valves (2) flushed the system completely and replaced the 8 way I noticed the unit heater came on.......!

~ 25' of 1" CPU to the aquastat, and the pipe was hot, this is not conduction, so the new valve is flowing water. I think the system is designed OK and this should not be happening... its just a small amount as this point as the return is still cold, but water is moving past the ball in the ZV.

I have a couple of choices, I could install a spring check, it might work and it might not, if not then I have wasted more time, if it works, how long will it last? Will I need to replace as they typically have a rubber seal and do a better job of stopping flow than a swing valve.

I could replace the circulator, if it fixes it, what happened top the pump to create more pressure...?

I could replace the ZV's with a ball valve style ZV, Taco esp or Bellimo.... I am leaning that way.

I appreciate the help.

Gardyloo

Roger said:

Thank you for your post, @Gardyloo .

You mention a buffer tank, do you have radiant tubing? It’s possible that that has deteriorated (black water) and no longer has an oxygen barrier. 8-Way has an oxygen scavenger and elevates the pH so there’s no corrosion, however non-oxygen barrier tubing and/or make up water can deplete and prevent proper long-term water conditions.
That boiler has 007 and a bypass, so there should be no problem with the head pressure on the zone valves.

Thank you,

Roger

Thanks for the reply Roger, I have three EK's on various properties and one is going on 30 years old, I find them to be excellent boilers.

Roger

Thank you for your kind with about our boilers, @Gardyloo !
Taco ESPs are excellent zone valves, but they can take a while to charge and open and the boiler may go off on high limit before they respond, so we don’t recommend them on System 2000 installations.  I’m not sure about Bellimo responsiveness. 

It sounds like you’re on top of things, but is it possible that the zone valve was manually open and bypassing?  Once powered, it will reset to closed after thermal purge is complete. 

Honeywell and Erie/Invensys/Schneider zone valves match very well with the system and should not bypass.
For reference, a 007 should not have any where near the velocity to cause erosion on metal parts.

Roger

Gardyloo

Roger said:

Thank you for your kind with about our boilers, @Gardyloo !
Taco ESPs are excellent zone valves, but they can take a while to charge and open and the boiler may go off on high limit before they respond, so we don’t recommend them on System 2000 installations.  I’m not sure about Bellimo responsiveness. 

It sounds like you’re on top of things, but is it possible that the zone valve was manually open and bypassing?  Once powered, it will reset to closed after thermal purge is complete. 

Honeywell and Erie/Invensys/Schneider zone valves match very well with the system and should not bypass.
For reference, a 007 should not have any where near the velocity to cause erosion on metal parts.

Roger

Hmmm, is there a dip switch setting we can change that would accommodate the TACO ZV?
How much time are we talking before it opens? I guess I can research that.

The zone valves were not by-passed on a regular basis, everything functioned as it should until this spring and the HO noticed the unit heater cycling for no reason, and then I noticed the temp in the buffer tank was above set point. Aquastat is set at 115/135 and tank was 152. fortunately the radiant heat control can handle the high temp, but its unnecessary to keep the tank that high IMO.


Both valves eroded and even the new valve is allowing some flow.

Do I try a different pump?







Thank you for your help. John

hot_rod

I would test the water

Gardyloo

hot_rod said:

I would test the water

Water has been replaced and typically treated with 8 way. It was tested at one point and has some minerals and very little iron.

The issue is the pressure from the pump is sufficient to push water past the zone valve's, its peculiar and I dont think it is a piping issue as I have had techs smarter than me look at it.

I may try just replacing the pump, which doesn't make much sense or different zone valves.

mattmia2

Maybe the bypass is stuck closed or clogged so the circulators are essentially deadheading on the zone valves.

hot_rod

I think those valves have a 20 psi shut off pressure, I doubt that 007 would push them open, even deadheaded?
Did someone remove one of the springs on the HW valves? That is a common hack if you ever had water hammer. That would lessen the valves close off pressure and you could leak past and erode away the brass.

A delta P circ is what I would replace that 007 with. It will modulate the pressure based on one, two, or no zones open. Amnd reduce electrical consumption!

Gardyloo

hot_rod said:

I think those valves have a 20 psi shut off pressure, I doubt that 007 would push them open, even deadheaded?
Did someone remove one of the springs on the HW valves? That is a common hack if you ever had water hammer. That would lessen the valves close off pressure and you could leak past and erode away the brass.

A delta P circ is what I would replace that 007 with. It will modulate the pressure based on one, two, or no zones open. Amnd reduce electrical consumption!

We have had water hammer......... but no one has messed with the springs, I appreciate the pump suggestion, any particular one you can recommend?

Gardyloo

mattmia2 said:

Maybe the bypass is stuck closed or clogged so the circulators are essentially deadheading on the zone valves.

The plate exchanger is essentially the by-pass, I just swapped it out with a clean on and it was clean,, typically it gets plugged on the domestic side and that was clean as well. There may be a 2nd by-pass on the back of the boiler that I am not familiar with, it was mentioned to day when I was discussing controls at a supply house.

hot_rod

Every pump manufacturer offers delta P circulators now. i'm most familiar with the Grundfos Alpha series. UPS E 15-58 is one of the newest models. Basically the pump modulates as valves open and close.

However, check with Roger, or System 2000 if there is an always open bypass circuit, then a delta P circ may not work properly. I would think they would offer delta P circs on any of the zone valved systems, if they are workable. They sure makes zone valves happier.

jringel

While I do like the delta p circulators, they do not work well with our boilers due to the permanent bypass we have through the plate exchanger. The plate exchanger would be the only bypass on the system. There is a half inch pipe in the rear of the boiler that some people believe is a secondary bypass but it is actually a vent to remove air from the center roll of the boiler. In regard to the taco zone valves they open just a touch slow which can cause the boiler to cycle off on the high limit, it only misses by a few seconds but the boiler is being overheated by about 20 degrees above design. There is no dip switch setting that will adjust for this. The taco 007 should not be able to cause the zone valves to bypass heat when closed with an operational bypass which you have already replaced. is the circulator installed in the correct orientation and is there anti-freeze installed in the system?

Gardyloo

jringel said:

While I do like the delta p circulators, they do not work well with our boilers due to the permanent bypass we have through the plate exchanger. The plate exchanger would be the only bypass on the system. There is a half inch pipe in the rear of the boiler that some people believe is a secondary bypass but it is actually a vent to remove air from the center roll of the boiler. In regard to the taco zone valves they open just a touch slow which can cause the boiler to cycle off on the high limit, it only misses by a few seconds but the boiler is being overheated by about 20 degrees above design. There is no dip switch setting that will adjust for this. The taco 007 should not be able to cause the zone valves to bypass heat when closed with an operational bypass which you have already replaced. is the circulator installed in the correct orientation and is there anti-freeze installed in the system?

circulator and zone vales are oriented correctly, no glycol.

From what I have learned the Taco and Belimo valves both have a capacitor, ~ 5-20 seconds to charge the capacitor and 60-75 seconds for the vale to open a full 90 degrees.

From the time the energy mangers sends the signal to the zone valve it is about a minute and half in the worst case, I suppose it would depend somewhat as to the status of the capacitor. However once the charge is done the valve stats to rotate open and water is flowing.

At least this is how I interpret it.

mattmia2

Measure the voltage on the zone valves when they are off, maybe somehow there is just enough current there to cause the motor to turn just a little.

SuperTech

Those Honeywell zone valves just are not a quality product anymore, it's as simple as that. I probably replace a hundred of them every year.  Most EK boilers I work on use Erie zone valves and I don't have many problems with them. The newer EK boilers use Caleffi zone valves, that would be my preference. Caleffi products are usually high quality. 

Lance

all good comments. Could have been as simple as a particle stuck long enough to start an erosion problem. Process of eliminating a cause may never find out why or could just chalk it up to job security as things wear out. the pic seems more like erosion over time. Cause unknown.

hot_rod

Depending on what you need from the zone valve, fast open? fast close, crack open?

The Belimo cracks open at 15 seconds, full open at 1:02, closed at 55 seconds
The Taco cracks open at 28 seconds, full open at 35, closed at 4 seconds
Caleffi cracks within 2 seconds, full open at 20 seconds, closed at 16 seconds

So if the goal is quick flow, the Caleffi is fastest to allow flow.
If you have a need for slow close, for water hammer issues maybe, the Belimo at 55 seconds to full close

I think Steve from Taco mentioned they are slowing down the close on the Zone Sentry? Mine appears to have a 12/22 date code.

If you do have an over pumped condition I suspect you will get some noise across the ball valve type zone valves as they near the end of the close. A small sharp opening across the ball may cause turbulence, flashing, possibly cavitation. Same as you experience with a typical ball valve you close by hand against excessive flow.

For most hydronic work, the paddle style zone valve, motor open, spring close, checks all the boxes.

Gardyloo

Thanks for all the replies, I have used Erie ZV's and they are excellent, not as easy to service as the Honeywell's from my limited experience. The Honeywell's are preferred by most plumbers around her and that could be just a regional thing.

Fast close VS slow close... not my area of expertise... I dont know what is best for this application, my gut feeling is slow acting should be OK.

I could install the ball valve style ZV, however if the issue is the pump or a piping issue then that remains unresolved, I am convinced the valve failed due to over pressure from the pump. If so then the new ZV may take care of that issue, however there could is still potential for high flow and the water could be scouring other fittings...? Just a possibility. maybe...?

I thank I will replace the pump first, if that solves the issue then great, if not I have a spare pump which is not the end of the world as I have several boilers with that pump.

Maybe consider using 005 for this system. thoughts...?

Thanks again for all the help and I will check voltage at the ZV this weekend, but not hopeful

hot_rod

I doubt the valve was over flowed or over pumped, looking at the components you have, no way no how.

As John at EK mentioned the slow opening of the ball type ZVs will be a problem. I suspect they have tried this. No need in trading one problem for another.

His mention of a bypass eliminates the pump deadheaded against the ZV.

Could be those valve bodies are not DZR dezincified brass. Or a below quality brass manufacturer? Over dose of the 8 way?
Certain water conditions can cause brass to dezinicify. IE the failed pex brass fittings and Zurn and other lawsuits

If you like Erie, you will love Caleffi zone valves.

jringel

I would recommend not changing the circulator over to the 005. You will not have the correct flow through the plate exchanger which will affect your hot water production. I would definitely check to make sure that the zone valves are not energized and if not would recommend changing the zone valves. another question would be have you had any flashing lights on the manager as certain error codes can open the zone valves. Also does the circulator and zone output light on the manager stay on after the post purge has been completed?

Jamie Hall

I'm looking at the zone valve balls... and that doesn't look like erosion damage. If I didn't know better, I'd say it was overtemperature or oxidation damage to the material of the ball. What is the ball made of?

hot_rod

Are those Buna rubber balls in the Honeywell, or EPDM I wonder?

Caleffi has been using peroxide cured EPDM in the Z-one valves. This is due to the harsh water conditions they see. So many different aggressive chemicals being use in public water systems now. Caleffi bodies are LL NSF rated and get used in potable water conditions.

Peroxide curing crosslinks the EPDM make it more resistant to aggressive water. Just as peroxide curing crosslinks pex tubing, for example.

Another thing about a ball instead of a flapper inside a zone valve. The ball closes in different locations, so you end up with multiple imprints that can leak across over time. The paddle type zone valves get an imprint in one spot and close against that same imprint. Less likely to get any bleed by. In over-pumped conditions especially.
Your ball, I mean the zone valve ball has those multiple imprints. Sad

You're sure one spring has not been un-hooked? How did you solve the banging/hammering issue of the past?

Gardyloo

I have no idea what material the balls are, they do look like they have been exposed to excessive heat based on the cracks. I dont think there is anything wrong with the valves. The damage to the body is from water flow. Damage to the balls is a question I cant answer. Other than the spring holding them in the flow just barely open rather than fully open or fully closed.

The important thing is the new valves are doing the same thing and allowing water to by-pass, minor right now as the valves are new.

I have not seen the pipe hammer myself, only reported form the current HO, I resolved that by opening the valve to HE fully, typically these are placed in a 45 position to minimize flow to the HE. This is what I recall as a setting by EK.

3 quarts of 8 way should not be excessive in a 80 gallon system, boiler, 40G buffer, unit heater, floor tubing, I did the calcs and cant remember the exact amount at the moment.

I have not seen any closed the EM, will check the voltage at the ZVs as soon as I get a chance.

You got to admit, its a good one...! I will persist until its sorted out...!

kcopp

My 2 cents is that the 8 way is the culprit.
Why is it in there to begin with?

I would flush all of it out of the system. Let a good cleaner remove all the debris and flush out again.
Then replace that w/ a DI water mix. Axiom makes a good filter.

I have seen this degradation w/ other products (fernox in particular)
Fernox claims you cant overdose...

It has left me w/ a less than great taste in my mouth...

Roger

@kcopp , Energy Kinetics includes 8-Way with every boiler, and has done so for decades. It has an oxygen scavenger and increases the pH to a level that prevents corrosion, among several other things which are very good for the longtime service and reliability of hydronic systems.  It should be in the system, and the color indicator should be checked to make sure the pH level is appropriate. It certainly will not harm zone valve components. 

We have seen the balls on Honeywell zone valves degrade on very rare occasion, similarly, this sounds very site-specific.

I would suggest replacing the zone valve with Erie or Caleffi since you had an issue with Honeywell and want to move in a different direction. Flush the system and add the proper amount of 8-way, and keep a 007 or equivalent circulator on the boiler.
Keep an eye on things and report back here, PM me or others on our team, or call our tech hotline at 908 735-2066 for additional help.
Thank you,
Roger

hot_rod

Any response from HW or Resido?
Ill bet their first request is a fluid sample😉

Gardyloo

hot_rod said:

Any response from HW or Resido?
Ill bet their first request is a fluid sample😉

I spoke to a rep in Minnesota, he tried to be helpful, but his firewall would not allow him to see the pics. I described it, but not much help w/o seeing it. Not much was said about the water, I did mention it was treated.. believe me its not the water. I had it tested when we completed the house, as I said before some minerals, some iron, no red flags, treated with a softener. No arsenic or anything odd. None of the techs I have talked to have mentioned seeing that from the local well water.

The valve is scoured from aggressive water flow, the new valve immediately started bleeding water past the ball. Water did not and could not deteriorate the valve body within minutes of bringing the system on line....

It is not the water or the 8-way.

hot_rod

Take a wire off the valve, that eliminates any voltage at the valve, is it still bleeding through?

Shut off head on a 007 is around 10', 4.3 psi.

Even the high 10 Cv, HW valves can shut off that delta P
8 Cv is the most common of the HW valves, it has an 8 psi shutoff.

I don't see a 007, even deadheaded against closed valves, pushing the valve open?

hot_rod

Send the HW guy the link to this thread, then he has the complete history. Seems he should have the most skin in the game. Certainly would want to know about multiple failed valves?

Did you say you filled with softened water. Does Rectorseal mention blending 8 way with softened water?

HomerJSmith

Just put in a Taco Sentry zv. It won't break the bank.

hot_rod

HomerJSmith said:

Just put in a Taco Sentry zv. It won't break the bank.

Did you read John’s post above about that valve opening too slowly. Causes the boiler to hit high limit and overheat design by 20 degrees?

Jamie Hall

I just love it when people say "believe me, it's not the [in this case] water". End of discussion. End of trouble shooting.

Gardyloo

Jamie Hall said:

I just love it when people say "believe me, it's not the [in this case] water". End of discussion. End of trouble shooting.

Ok, lets assume for a minute it is the water. How long do you think it would take for water to affect the zone valves? 

Jamie Hall

Depends on what is in the water vs. what the balls are made of. Anywhere from a few hours to a few weeks -- and it is a time, not flow, based problem.