Zone valve problems, please help


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Old 11-23-07, 08:07 AM
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Zone valve problems, please help

Hello evryone,
I have three honeywell v8043e1012 zone valves in my system. Two of them don't seem to work properly. I'm on my third set of motor assemblies from the oil company. The brass gears keep stripping. If I take the motor assembly off and turn the valve body stem by hand it only turns about a quarter inch. No matter wich way it is turned the hot water still circulates through it. The baseboards on these two zones are continuosely hot, even when the thermostats are disconnected and the circulator pump is not running. There is an additional zone on the system with its own circulator pump for the hot water tank. My assumption is that everytime the hot water tank zone circulates the water is also circulating through the two zones with the faulty zone bodies. (it seems like a crafty way for the oil company to make the system use more oil but I don't want to make accusations) Can anyone tell me how far the valve body stem should turn? How do I prove to the oil company that the valve body is in fact defective and needs to be replaced? I'm assuming that I cannot take the plate off the top of the valve body myself to have a look inside without the water coming out. Any help is appreciated, Thanks, Jeremy.
 
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Old 11-23-07, 09:59 AM
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My zone valves are the Honeywell MZV series, they apparently work differently than yours? If I remove my power heads, the valves will go to the open position, they use a plunger type valve, not a rotating one. I take it your zone valves use a rotating ball valve type control?

I took a quick look at the Honeywell site, and it appears that your valve has a replaceable ball valve, there should be no need to replace the entire body if comes to that. There could some junk binding the valve causing the problems you are having. The big question is WHY would they replace four power heads in a short period of time without investigating the cause of the problem??? What was the time interval between failures? Did they charge you for what should be warranty coverage (if the failures were in short order); or do you have a service contract for these repairs?

Pete
 
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Old 11-23-07, 10:42 AM
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Originally Posted by ctfl1 View Post
...If I take the motor assembly off and turn the valve body stem by hand it only turns about a quarter inch...
Jeremy, you meant to say 1/4 INCH and not 1/4 TURN ? Just checking...

no, don't disassemble the valve without draining first, and a cool boiler. Pete, where did you see the replaceable ball valve on Honey's site ?

Is this a new installation that hasn't worked properly since day 1 ? If so, I'd wonder about installation problems. Can you post some pics that show the near boiler piping ? If so, put the pics up on www.photobucket.com (free) and post a link here so we can take a look see.
 
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Old 11-23-07, 11:31 AM
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Trooper, from this Honeywell file. I am not sure if that ball is supposed to rotate, or if it is a plunger type seal?? Look at the parts breakdown.


Pete

http://customer.honeywell.com/techli...0s/60-2133.pdf
 
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Old 11-23-07, 11:48 AM
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OK, got it ... I was looking at the install PDF a little further down the list.

I think it rotates, 1/4 turn...

Those directions seem to be for installing the conversion kit to use the old valve body with the new power head.

Makes me wonder... if it's _possible_ to install a new power head on an old valve body WITHOUT doing the conversion, and maybe ... just maybe ... this is why the gears keep stripping out ? Might not even be possible to do so, but stranger things have been seen ! (arghhhh, why is this tab in the way ? I'll just cut it off ... arghhh, there ya go, NOW it fits! arghhhh, that's a SHARP INSTALLATION!)

I think it might also be worth a look to see if the valve body was installed in the correct direction !
 
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Old 11-23-07, 11:55 AM
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Direction issues usually cause water hammering problems. i'm still not sure if that is a rotating valve, or a plunger type system. Most zone valves use compression, not rotation, in my limited exposure. Wish Grady was here. But it sounds like either an installation problem, or interference in the valve body?

Pete
 
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Old 11-23-07, 02:34 PM
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additional info

Thanks for the feedback. That was exactly my question to the oil company the first two times as to why they just replace the motor assembly and not fix the valve. I’ve since cancelled my contract with that company and have just contracted with a new company. I have a service call in to them but with the Holiday I don’t expect to hear or see them before next week. The old company had replaced the valves within a span of about a year and a half. Some of the work was covered under contract and some of it I paid for. I've paid for all the oil the system has used though, and it runs quite a bit. Originally I thought it was the hot water tank that kept calling for heat but then I noticed the other day that the two zones were producing heat again even with the thermostats off. I even disconnected the thermostats altogether to make sure it wasn't them. I’ll try to get some pic’s. I’ll post when I get them up. The shaft turns about 1 hour position on a clock dial. No matter which way it is turned the water flows through the zone. The diagram here http://customer.honeywell.com/techli...0s/60-2133.pdf on p. 12 & 13 is exactly what I have. The last time the service tech. was here they put on the conversion kits and new motor assemblies but still did not change out the valve body assemblies or anything inside them. With the conversion kit installed can I take off the adapter plate as shown in fig. 11 without draining the system? Thanks again for your help, Jeremy.
 
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Old 11-23-07, 02:56 PM
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the ball moves on an arm somewhat like a toilets flush handle lever. the valve arm sometimes will get tight. if you remove the head and work the arm back and forth a few times it will free up.use a pair of plyers if you have to, then put a little silicon grease on the slot the re-install the head.

If you went through that many motors you must have the valves installed on the output side of the boiler. These valves dont like high heat for some reason. They seem to last longer and work better when installed on the return side.
 
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Old 11-23-07, 02:58 PM
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Originally Posted by ctfl1 View Post
The last time the service tech. was here they put on the conversion kits and new motor assemblies but still did not change out the valve body assemblies or anything inside them. With the conversion kit installed can I take off the adapter plate as shown in fig. 11 without draining the system? Thanks again for your help, Jeremy.
No!, if you take out those 4 screws, you've got water all over the place!

But... but... I thought the conversion kit included a new ball and O-ring ? At least that's what it appears to be in the PDF. A new mounting plate, ball and shaft, O-ring, 4 screws.

I'm waiting to see how your system is piped. There's a possiblity you are suffering from what is called "Ghost Flow", but that still doesn't explain why the gears keep stripping.

Ghost Flow

This happens more with circulator zoned systems, but can happen with a zone valve too. Believe it or not, there can be bi-directional flow in one pipe. Hot water flows out at the top of the pipe, and cold flows back on the bottom.
 
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Old 11-23-07, 03:55 PM
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more info; pics uploaded

Ok, uploaded pic's.
http://i227.photobucket.com/albums/dd171/ctfl1/11.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/6.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/3.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/2.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/1.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/4.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/10.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/9.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/8.jpg

If i've figured out photobucket correctly these should be direct links to the pictures.
The valves are directly after the expansion tank on the hot side of the system, and yup they're hot enough to burn, found that out quick.
#11 shows the underside of the three zone valves
#6 shows the top side with all three motor assemblies on
#3 shows the left motor assembly removed
#2 shows the top adapter plate with the shaft turned all the way counter clockwise
#1 shows the top adapter plate with the shaft turned all the way clockwise
#4 shows the manufaturer info on the motor assembly
#10, 9, & 8 show larger views of the plumbing.
in #9 you can see four return lines in front, one of the zones is spit into two, these all come together into one line and then you see the circulator pump at the bottom of the picture. The circulator pump for the hot water tank is behind the boiler out of view. On the top right of the boiler you can see the outflow pipe coming up to the expansion tank, the line that's t'd off right after it comes out of the boiler is the line to the hot water tank, after the expansion tank the line splits into the three zone valves, the first one is a 1" line (which I assume is the one that splits into two return lines somewhere in the system) this one is working ok, the two behind it are 3/4" lines, these are the two that are not shutting off. As you see in pic's 2 & 1 no matter which way the shaft is turned the pipes on the outflow side of the valves remain scalding hot and the baseboard radiators put out heat.
Thanks again for all your help, Jeremy.
 
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Old 11-23-07, 04:14 PM
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one additional note

In pic's 11, 6, and 3 the 1" pipe that seems to be working properly is all the way on the right. The pipe after this zone valve is cool when the zone is not calling for heat. When the thermostat calls for heat the zone valve opens, turns on the circulator, and the pipe after the zone valve gets scalding hot. After the thermostat turns off, the zone valve closes, the circulator pump turns off and the pipe after the zone valve cools down again after time. The middle valve in the picture does all the same except the pipe after the zone valve always stays warm to hot. It never cools down even when that zones thermostat is off. The valve on the left does all the same as #2 except the pipe after the zone valve is always scalding hot and the radiators in this zone are radiating heat. Even after that zones thermostat has been disconnected for days. It would appear that the valve inside the body of the left valve does not shut off the water flow when the zone valve turns off; the middle valve appears to be leaking by but not fully flowing when it turns off; and the one on the right appears to be doing what its supposed to
 
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Old 11-23-07, 04:40 PM
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Everything I see so far looks just fine. I wish my system looked so good !

Can you get some shots of the connections to the water heater ?

I highly doubt that system is 'ghosting' ... you are probly correct that there's some problem with the zone valves. BUT... that amount of travel on the shaft looks like durn near a quarter turn to me. I think that's about right. There just might be some debris under the ball seat, or when they were installed they used too much heat and damaged the ball. I don't think you need to replace the bodies, but I'm willing to bet if you drained the system and opened them up you'd find your problem right away.

Check this out: Patriot-Supply 8043 parts

I can't see where that gear appears stripped... could just be normal wear and tear ... I mean, it's still opening and closing the valve, right ? even thought the valve isn't sealing shut ?

I'm going back to look at the pics some more... might print one out as a 'pin-up' !

---editorial comment unrelated to the problem at hand---
You want to make an improvement ? (I'm gonna sound like Grady, watch...) Get rid of the zone valves and install three circs, each with an integral flo-chek valve. Get a four zone Taco panel, snip-clip, heave ho the lo-voltage wiring.
-----------------------------------------------------

The ONLY nit-picks I can do on that install is the fact that it's not set up to 'pump away' from the expansion tank, and replacing the zv's with circs would take care of that. Also, on the return manifold, there are four valves... are those drains ? or shut-offs ? either way, there really should be BOTH, to allow proper purging of the loops, but like I sed, I'm nit-picking so ignore me.
 
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Old 11-23-07, 09:04 PM
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Grady, Grady, Grady

What am I gonna do with you guys. Ok, Grady finally made it. It's been a tough day. On to the problem at hand.

It is quite odd for valves to eat motors as yours is doing. I may replace half a dozen motors a year out of hundreds of systems with Honeywell zone valves. The discoloration around the valve stem concerns me but I don't see any corrosion as if the stem seal had been leaking. One thing which will cause trouble is uneven tighening of the powerhead onto the plate or the motor being crooked for some reason, such as the plate being warped. I can't help but think there is a problem with the valve body &/or plate. Another thought: Check the temperature of the boiler. Those valves are rated for a max of 200º.

The reason those zones are hot is with the valve head removed, there is no spring to hold the valve closed.

Trooper is right. If you remove that plate, water is going to come out. He's also right about my feelings toward zone valves in general. I would second his suggestion about doing away with the zone valves but that is not likely to happen under contract.
 
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Old 11-23-07, 09:56 PM
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ctfl1,

Want a good do it yourself opportunity? This would make a great project and create a more robust solution that you could more easily maintain.

You need 8 isolation valves, 4 circs (Grundfos 15-58 would be an easy choice - likely low speed), a zone control relay (Taco SR50# where # is the number of current plus potential zones. Get the EXP model if you ever want to add outdoor reset. On a conventional boiler, the Taco PC-700 which plugs into the zone circ controller would be my such for an outdoor reset controller.

About $200 total for the isolation valves (you'd need new ball valves anyway so these are a bargain) maybe less for your size. The pumps are easily less than $100 each and the zone controller is under $300 and can be well under $200. Even the ODR controller is excellently priced at under $300 and couldn't connect any simpler. maybe add a wye strainer for $20 or so. Copper fillings and pipe on top of this, and a bit of electrical.

The big question here is if you understand how to prep your boiler - safely off, no risk of dry-firing, only as many sections drained as needed. If you're fine with the wiring or could bring in help. Same with the piping. The guys here could easily come up with a great piping method for you.

It would actually be a pretty good way to learn how to solder if you can't already. The beauty of soldering done directly on the heating system is that you can use cheaper pipe (M), you can use 50/50 lead solder which is so much better and easier than working with leadfree solder, the pressure risk is much lower, it can only leak so much (provided that some form of LWCO protection be your first project if not so equipped yet). And as long as you follow basic soldering techniques and clean and wipe your joints fine you can do a job that you'd be quite proud of.

I'm adding second zone for underfloor heat in my kitchen. I bought my Taco SR503 and another 15-58. Looking forward to keeping some free spots in time over the next while.

Yup, if it were me, I'd start plumbing in some isolating flanges for a little bit of Danish pumping. It would look great and work much much more reliability while providing you fail-over protection should one circ die. You could keep a spare one on hand in the ready for if and when any finally die.

As you can see from the costs involved, there is a lot of equipment costs involved. Getting this done professionally would add greatly to the cost if you think that you could do a good job on it yourself. The mechanics and electricals, measuring etc on this are simple enough. Some soldering and boiler wiring tinkering required.
 
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Old 11-24-07, 02:09 AM
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well the first no no was to install the valves horizontally with the heads up on the output side of the boiler. The heads with the electrical componets are on top at the hottest point working like heat syncs. That's one reason why you have been going through those motors. It would be better to have the heads located under the valve bodies on that type of installation.

There are no isolation ball valves installed on either side of the zone valves to allow you to service the bodies without draining the entire system. Always spend the extra 15 bucks in ball valves to isolate each valve body on installation

The valve body access plate in the picture looks like it has taken a lot of heat as the metal is discolored. Does the valve lever turn easy or does it feel tight?
 
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Old 11-24-07, 02:48 AM
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Good morning everyone and thank you for all the great info.
I'll get some more pics of the connections up probably tonight or tomorrow. The shaft turns freely with no effort at all. With the motor assembly on it appears to work properly except that the water flow never stops, even when its off. Its almost as if there is no ball inside the body.
I'll check the boiler temp. as well and post it.
Thanks,
Jeremy
 
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Old 11-24-07, 10:34 AM
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I'm looking at that discoloration that you guys mentioned on the mounting plate. That sure looks like SOLDER around that shaft ... are those collars soldered at the factory like that ? or did someone do that 'after the fact' ? If that was done after for some reason (knuckleheadism?) then for absolute certain those valves have melted balls ... ouch!


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I answer myself, lame enough to make me wanna go away and not come back...
 
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Old 11-24-07, 11:24 AM
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At least for my MZV525, Honeywell advises removing the valve before soldering to protect the seals from heat damage.

Those valves should not be mounted with the motor facing down--Honeywell shows the preferred mounting positions in their literature. (A valve leak would allow water to enter the motor box.) http://customer.honeywell.com/techli.../95c-10819.pdf

You could move the zone valves to the return side (preferred to avoid water hammering and the valves will be cooler) but you will need a flow check on the supply side or a circulator with an internal IFC. That would be a good time to move the circulator to right after the airscoop so you are pumping away from the bladder tank, as Trooper noted. I would find out why those valves are failing so quickly before going off on any tangents with major repiping projects, especially if the system worked well in the past. Someone may have hosed those valves up on a previous repair attempt, and that could be the problem as Trooper , Grady and others noted..

Replacing the zone valves with individual circulators is a poor engineering unless one knows what the individual zone heating loads are--three oversized pumps to do what one small one could do alone???

Grady, I stand corrected on the temp. range for those valves, my MZV525s are rated for 240 degrees ambient and I assumed that applied to the entire product lime..
 

Last edited by radioconnection; 11-24-07 at 12:23 PM.
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Old 11-24-07, 01:19 PM
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Originally Posted by radioconnection View Post
Replacing the zone valves with individual circulators is a poor engineering unless one knows what the individual zone heating loads are--three oversized pumps to do what one small one could do alone???..
Not really... ya think he would be having this problem if there were circs instead ? unh-unhhhh...

But, as stated, just repairing the valves is all that's _needed_ at this point. It'll work fine once those old melted balls are castrated, and new ones sewn in.
 
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Old 11-24-07, 01:24 PM
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Originally Posted by NJ Trooper View Post
Not really... ya think he would be having this problem if there were circs instead ? unh-unhhhh...

.
Depends on if the same butcher who worked on the ZV worked on the circulators. There are a lot of ZVs out there working flawlessly. He shouldn't be having repeat problems with Honeywell valves.

Pete
 
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Old 11-24-07, 01:41 PM
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True! They'd probly all be piped up without a flow-check in sight, and then there would be heat in ALL zones every time that indirect called ... and on top of that, I bet the motors would be vertical !
 
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Old 11-25-07, 03:38 PM
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additional pic's

Here's some more pictures of the system and plumbing.

http://i227.photobucket.com/albums/dd171/ctfl1/12.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/13.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/15.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/16.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/17.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/18.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/19.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/20.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/21.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/22.jpg
http://i227.photobucket.com/albums/dd171/ctfl1/23.jpg

After reading Grady's post that the valve will not close off without the motor unit spring holding it off I took a pair of vise grips and clamped them onto the shaft, turned it closed, and then pinned it there with pressure. That seems to have turned off the zone. The pipe after the valve is now cool and there is no more heat radiating from the radiators on that zone. So it would appear that the ball inside the valve is working (although I did put strong pressure on it with the vise grips, I don't know how much pressure that ball should receive from the motor spring). Still the question remains as to why the gears keep stripping out on the motors. I'll get a new motor assembly this week and put it on. I'll keep you posted as to what happens
Jeremy.
 
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Old 11-25-07, 04:01 PM
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OK, knock one of my nitpicks out the window, you do have shutoffs and drains on each return... good !

Why have you got a triple aquastat if you are running an indirect ? You aren't using the tankless coil, at least I don't see any piping to it. Was the indirect added later ?

OK, this is only a MAYBE ... I see that the indirect circ is piped off the supply side, that's OK, BUT... I wonder if it's creating enough suction to pull the zone valves open and cause flow through the heating loops in the opposite direction on an indirect call ... could be ...

I see what looks like a check valve on the return from the indirect, so when the heating circ runs, you don't get flow through it, but the opposite might not be true. You might need to have some flow checks installed on the heating loops. maybe...

edit: Yanno, the more I think about it... that ball in them valves is just being pushed against the seat by a spring. When the heating circ is running, and a zone is NOT open, that ball will only be pushed harder against the seat. But, when the indirect circ is running, and there is suction on the supply side of the zone valve, it probably can easily pull it open.

Is the indirect circ wired as "priority" somehow ? In other words, can the indirect circ run, and a heat call from the house still cause a zone valve to be opened and the heating circ to run ? Or will an indirect call tell the heating to 'wait until I'm done' ?
 
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Old 11-25-07, 05:34 PM
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Originally Posted by ctfl1 View Post
So it would appear that the ball inside the valve is working (although I did put strong pressure on it with the vise grips, I don't know how much pressure that ball should receive from the motor spring). Still the question remains as to why the gears keep stripping out on the motors. I'll get a new motor assembly this week and put it on. I'll keep you posted as to what happens
Jeremy.

Vise grips?!?! Strong pressure? I think you've found why the gears are stripping. How much torque is needed on the good valve's stem to operate that ball valve? That don't sound right to me. Maybe Grady can chime in.

Pete
 
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Old 11-25-07, 05:54 PM
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Strong Pressure

Those springs are pretty stout but I don't think it should require "strong pressure" to keep the valve closed. If someone were so inclined, it would not take a lot to determine how much pressure those spings exert.
After several motors, I would be inclined to replace the entire valve, body & all.
 
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Old 11-25-07, 06:34 PM
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Hi guys, thanks again for all your help.
bear with me, i'm a jack of all trades and have mastered some, although this one i'm still learning
The easy one first... all three valves stems operate freely. However to stop the flow past the valve on the left I clamped the vise grips onto the shaft, then when the shaft stopped turning freely on the closed side I twisted a little more with the vise grips to get the ball to seat as tight as it could.
Now the learning curve... I'm assuming that the triple aquastat is the controller on the front of the boiler? That's going to be out of my understanding until I learn more. Is the tankless coil the hot water heater? And is that what you refer to as the indirect? I just went and studied the piping on the system a little more and I think I'm starting to see where a problem may lie. The hot water tank line is T'd off right after the outlet from the boiler. That line has it's own thermostat inside the hot water tank and its own circulation pump. The return from the hot water tank is T'd back in just before the in line to the boiler. So if I'm figuring correctly... without any sort of check valves in the radiator zone lines ( I don't see anything that looks like it would be that sort of thing ) then when the hot water tank zone runs it could potentially suck and push water backwards through the radiator zones. Would adding flow check valves solve that potential ? As far as the indirect having priority over the heat zones I don't know. That seems pretty sophisticated for that little mechanical control box on the front of the boiler. I don't see any circuitry that says it could actually think like that or any settings to make it do that. So I would have to say no, it doesn't have any priority. I'm actually pretty sure that I've witnessed both running at the same time.
For reference; pic 16 shows the line for the hot water tank leaving the boiler. The circ is in this line just before it goes into the hot water tank. pic 19 shows the return line from the hot water tank coming behind the boiler. pic 20 shows the return line T'd back into the return to the boiler just below the circ pump for the heat zones. Is this a typical sort of set up for a hot water heater connected to a boiler?
Thanks,
Jeremy.
 
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Old 11-25-07, 07:23 PM
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ctfl

I don't think you have a tankless coil, or at least it isn't hooked up. Don't worry about that.

The indirect appears to be that blue tank next to the boiler. Isn't it an Amtrol BoilerMate? That is what makes your domestic hot water.

Before you get carried away installing flow checks, why not test the therory? Here's how: Turn all room thermostats all the way down & leave long enough for the pipes to cool. Turn on the hot water to the washer or bathtub & just let it flow. When the boiler fires to make domestic hot water, allow it to run for a while & start feeling heating loop pipes. If you feel heat going out toward the rooms, maybe it's time to look into flow checks. Be sure to check both supply & return sides some distance from the boiler.
 
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Old 11-25-07, 08:03 PM
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And my guess is yer gonna feel the returns getting hot first...

Jeremy, what you explained about the pushing and pulling was what I was trying to say in post #23, and also why I asked to see the piping to the indirect. My gut is telling me that the indirect circ is pulling enough suction to cause flow past the zone valves. You may also have damaged balls too ... (minds outta the gutters boys) ... so you could be looking at two problems. Maybe if the valves were not damaged, you would get a better seal, and the indirect wouldn't be able to force flow in reverse past them.

But, do Grady's test... let it all cool down and see what happens when you cause the indirect to call for heat.

And then, work the other way... turn all stats down, let the loops cool... call for heat on ONLY the one that DOES seal properly. Do you get heat in the other two zones also ?

I think it will help greatly to know if it's ONLY when the indirect pump is running that you are getting unwanted flow, or if it's whenever ANY zone is running. That should narrow down the problem some.

Let's go all the way back to the beginning... why were the powerheads replaced the first time ? Same problem you have now ? The gear in that pic doesn't look stripped to me. When I think 'stripped' I think all chewed up with no teeth. What I see looks like just a little bit of wear on the teeth. I wonder if there were no reason to change them in the first place ? Did replacing the powerheads ever actually FIX anything ?

Yes, your aquastat is that control box. That round plate behind it is where a 'tankless coil' would be mounted. A tankless is exactly that... no tank. It's just a coil of pipe inside the boiler that exchanges heat to the water as the water flows through the coil. No storage at all. Are there any pipe nipples on that round plate ? Tankless coils are the worst way to heat water, your indirect is the best. But, if there are no nipples on that plate, then I'm surprised that you have the type of aquastat that you have. Your boiler stays hot all the time, yes ? That's because that aquastat is designed to do that so that if there WAS a tankless coil installed, the boiler would be hot and hot water would be available to the house.

You would have to have another control box somewhere to set up the 'priority' for the indirect. I wondered if there was something out of view of the pictures. No, you probably don't have that setup.
 
  #29  
Old 11-25-07, 08:12 PM
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Priority

Priority can be done with a SPDT relay. N/C would power the transformer for the zone valves & N/O would go to the aquastat on the indirect. Crown used to have it in one of their install manuals. Either for the CT series or Megastor indirect. Can't remember which right now or it may not even be there in newer versions of the manuals.
 
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Old 11-26-07, 11:03 AM
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work that vise grip back and forth like that a few times to clear it.
It sounds normal to me that you need a lot of pressure to hold the valve shut when the circulator is running. Push the manual lever and feel how much pressure is needed to move the lever to the manual lock. Between the motor and the spring there is a lot of resistance.

I don't think the indirect plumbing is giving you the problems. Time to replace the head and not just the motor if the valves are not staying closed.

As I said before those valves don't like heat. these motors and end switches go a lot on those heads. The heads would last much longer being underneath the valve bodies even though honeywell doesn't suggest doing so. Even if you could install them on their side would help.

The best solution would be to move them to the return side and put isolation valves on either side of the valve bodies.

The airscoop back is all cast and black iron and holds the heat very well
 
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Old 11-26-07, 04:01 PM
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Zone valve mounting

The company for which I used to work installed dozens of Energy Kinetics System 2000 boilers. Every single one of them had the zone valves on the supply side although the valve body was verticle. Some of these boilers have been in 20 years or more & I can't recall having to replace more than one valve, motors yes but not valves.
 
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Old 11-26-07, 04:18 PM
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Originally Posted by Grady View Post
The company for which I used to work installed dozens of Energy Kinetics System 2000 boilers. Every single one of them had the zone valves on the supply side although the valve body was verticle. Some of these boilers have been in 20 years or more & I can't recall having to replace more than one valve, motors yes but not valves.

grady

the electrics on the valve is what doesn't like the heat. the valves are pretty reliable

honeywell has made a bundle out of selling replacement heads for their valves
 
 

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