Bad Zone Valve or Thermostat?

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Old 12-06-13, 08:27 AM
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Bad Zone Valve or Thermostat?

We purchased a new home with a new Peerless boiler a couple months ago. It has baseboard heaters with 3 zones, the upper, the main level, and the lower level. Now that its getting below zero at night here in Minnesota, I can definitely tell the main level is not heating properly. The supply pipe coming out of the boiler is very hot, the lower and upper zones seem to be heating properly and the pipes near the zone valves are hot which means the hot water is cycling ok. the pipes by the main level zone valve are cold and the thermostat reads between 60-68 when its set to 70 degrees. This must mean the zone valve is bad??

To complicate this more, yesterday all of the zones were working fine and cycling hot water. Last night all three zones had cold water and their respective thermostats were reading 5-8 degrees below the set level, which has never happened before.

The issue seems to be intermittent, is this simply bad zone valves or could it be the thermostats too?? the chronic zone valve is pretty old, erie brand?

Where do i start?? Thanks in advance for any help.

Also, when the hot water is working correctly there is a constant sound of running water throughout the house, It sounds like this is air in the system which could be adding to the issues. At times there is also some somewhat noisy banging from the room with the boiler, is that another symptom of air in the system?
 

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Old 12-06-13, 09:17 AM
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Where do i start??
Find the pressure and temperature gauge on your boiler and tell us what the readings are.

It sounds to me as if you don't have enough water pressure in the system and this is contributing to the problem of air in the system, which is messing up the flow of water...

Can you take pictures of the boiler installation please?

I would like to see the gauge and also the pipe that feed the water from the domestic piping to the boiler piping... and any valves on that pipe.

Don't stop there though, take pictures all around the boiler so we can see what you've got.
 
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Old 12-06-13, 10:13 PM
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Thanks again for the help!!

Here are the picture of the system.

Came home tonight to the "overheat limit open" error on the main screen of the boiler, it was a cool 58 degrees in our house, (-4 degrees F outside) it needed to be reset to start back up; this error has came up several times in the last few months.

The smaller vertical pipe with the two yellow shut off valves is where you would add water to the system from the well, I think.

The 4th picture down, the close picture of the zone valve is the one that is not working.

When the boiler is on standby the pressure goes way down to zero, is that normal?
 
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Old 12-07-13, 10:57 AM
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When the boiler is on standby the pressure goes way down to zero, is that normal?
No, not at all, and is likely at the root of your problem.

Before I start 'critiquing' the installation, may I ask who installed this? Yourself? Relative? Friend? I presume not since I think you are saying that the boiler was in place when you purchased the home?

The first thing I always recommend is to service the expansion tank. These tanks are sadly mistreated and NEVER serviced. Read this for more information, and follow the step-by-step in the post to make sure your tank is working properly. This should be standard preventative maintenance.

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

Your gauge is 'probably' OK, but also look at this one for reference:

http://www.doityourself.com/forum/bo...ure-gauge.html

It appears to be a "Purefire", but what specific model is your boiler?

The smaller vertical pipe with the two yellow shut off valves is where you would add water to the system from the well, I think.
Yes, it appears so. What I don't see on that pipe is a "Pressure Reducing Valve". Is there anything that looks like this (or similar) on that pipe?


image courtesy pexsupply.com

All I see is the two yellow handle ball valves and a 'backflow preventer'.

At this point I do NOT believe that you have a zone valve problem. Instead you probably don't have enough pressure in the system... and you have air pockets blocking the water flow.
 
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Old 12-07-13, 11:03 AM
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Typically, heating systems should have a MINIMUM PRESSURE of 12-15 PSI when the system is COLD.

NEVER feed cold water to a HOT boiler! ALWAYS turn the boiler off and allow to cool to 100F or less.

Since it does not appear that you have a pressure reducing valve installed which would automatically feed water when the pressure gets below this point, you will have to pay attention to the pressure gauge. Make sure it never goes below this pressure by opening the yellow valves and bringing the pressure up when needed.

Thing is, the system should NOT lose pressure by itself. It's CLOSED, and the pressure should remain.

If it consistently loses pressure, bottom line is that somewhere... there is a slow leak.

I don't see any provision for automatic air removal either... no air scoop, no automatic air vents...

I'm sorry to say, in my opinion, this is a poor example of boiler installation.

Do you have the manual for the boiler?
 
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Old 12-08-13, 11:34 AM
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The model is a Peerless Purefire PF110; this was installed prior to us purchasing the home. I have been reading the manual I have and familiarizing myself with the system as much as possible.

To correct a prior statement, I believe when I saw the pressure at 0 was when the "overheat limit open" error had happened a few times and the boiler had shut down. Although when the boiler is on standby the pressure seems to drop below 10 psi, when the pump is running it reads close to 15 psi.

There is nothing that looks like a pressure reducing valve or anything for automatic air removal (microbubbler? air eliminator thing) nor is there anything on the baseboard heaters for removing air. Would air removal from the system consist of opening the manual valves above the zone valves and pushing the air out? Would you recommend installing an air vent?

As I am sitting here now the upper and lower zones are reading 70 and 71, which they are set at, the main level zone is reading 67 and the thermostat is set to 71. The boiler is currently on standby, does that mean its still cycling the main level zone or is it not cycling anything through any zones?

We do have a 1 year home warranty and I have contacted the company about the issues. They sent out a mechanical contractor who did not seem very knowledgeable about what is happening. All three zones were cycling fine when they were here and they basically said that we need to remove the air from the system. They are replacing the zone valve, which he determined was broke because the manual lever does not spring back or grab anything when you move it, it is loose and just jiggles around loosely.

I will take some of the info you have shared with me and talk with the technician about it when he comes this week.
 
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Old 12-08-13, 12:23 PM
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I believe when I saw the pressure at 0 was when the "overheat limit open" error had happened a few times and the boiler had shut down
Not surprising at all. These boilers need a minimum flow rate through them to operate properly and prevent damage to the heat exchanger.

You system is piped very poorly, and not at all in accordance with the manufacturers recommendations.

Every single one of the diagrams in the install manual show the boiler piped in what is called a 'primary/secondary' arrangement, and yours clearly is not.

Every bit of that installation cries out to me: " DID NOT READ INSTALLATION INSTRUCTIONS, DID NOT CARE, THOUGHT HE KNEW BETTER THAN THE MANUFACTURER".

In addition, very poor execution of even the WRONG job that he did. Crooked pipes, tied in 'knots', case in point: no installer in his right mind would loop the pipe into a circulator in a spiral like that.

Manufacturer specs trump all others, and Peeless wants 14.5 PSI MINIMUM.

2. The minimum system pressure is 14.5 psig
page 17 of manual

Honestly, if I was faced with that as MY system, my first reaction would be to put a new blade in my Sawzall and start over.

I know this is harsh, but it is what it is.
 
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Old 12-08-13, 12:29 PM
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They sent out a mechanical contractor who did not seem very knowledgeable about what is happening
Great... just what you need at this point... ANOTHER graduate of "Bozo's School of Plumbing and Heating".

They are replacing the zone valve, which he determined was broke because the manual lever does not spring back or grab anything when you move it, it is loose and just jiggles around loosely.
Yes, this is EXACTLY what you will find if the valve is ALREADY OPEN under thermostat control. The ONLY time you will feel any resistance on that lever is if the valve is CLOSED and the thermostat is not calling for heat.

I would bet that if you turn that thermostat all the way down and try that lever again, you will find that it is NOT loose and jiggly.

As I am sitting here now the upper and lower zones are reading 70 and 71, which they are set at, the main level zone is reading 67 and the thermostat is set to 71. The boiler is currently on standby, does that mean its still cycling the main level zone or is it not cycling anything through any zones?
If the boiler is on 'standby' it means that it is not seeing a heat call.

Does the thermostat indicate that it's calling for heat?

You MAY have a bad zone valve... but it's not the lever that's the problem, it would be the device called the ENDSWITCH inside the zone valve.
 
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Old 12-08-13, 02:13 PM
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The thermostat is sending a call for heat and the boiler continues to stay on standby.

I turned the heat way down, below the room temp, in the main level zone and the heat turned off. I waited a few minutes and checked the problem zone valve. It was still very loose and jiggly, with the cover off you can see the lever isn't attached to anything and there is some plastic that looks like something has broke off of it. Just from looking at it it seems that something isnt right with it, its different than the other two zone valves so its hard to compare them.

This is all really disappointing, especially since this is our first home purchase. The boiler is brand new and they obviously tapped into the existing layout to make it easier, but didn't do it properly. I looked at the layouts in the manual like you mentioned, it is definitely far from what the manufacture recommends as far as piping and zone layouts.

Maybe I will get another technician out this week that might know what he is talking about and we will be able to tackle some of the bigger problems your mentioning.

The main level zone has now reached the thermostat level of 70 degrees It makes no sense to why it gets there sometimes and is freezing in here other times.

I might have to go and dust off the sawzall
 
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Old 12-08-13, 02:28 PM
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The thermostat is sending a call for heat and the boiler continues to stay on standby.
In that case, the zone valve would seem to have a bad endswitch then and at least the power head needs replaced.

The way zone valve (ZV) works is: Thermostat calls for heat... thermostat is connected to zone valve motor, NOT to the boiler. There is the endswitch inside of the ZV head, which IS connected to the boiler and when the valve is fully open, there is a 'cam' inside the ZV head that pushes on that endswitch to tell the boiler to fire. So the ZV is a 'pssst, pass it on' type of device. The valve can open, and if the endswitch has failed, the boiler won't respond.

The main level zone has now reached the thermostat level of 70 degrees It makes no sense to why it gets there sometimes and is freezing in here other times.
You WILL get heat in that zone if ANOTHER zone simultaneously calls for heat though, because the OTHER zone is calling for heat and since the bad valve IS OPEN, you will get flow in the bad zone as well.

So, when you need heat in that room, push another t'stat up to get some flow...

This is all really disappointing, especially since this is our first home purchase.
I understand, and I know it's frustrating and disappointing, you have my empathy if that's any consolation! It's too bad that home inspectors are not better trained, and the fine print in their contracts says "... no liability for stuff I screwed up on ..." , thus it seems you have zero recourse for anyone to 'make it right'. If the HI had been on his game and mentioned in his report that the boiler was installed poorly, you would have had a bargaining chip to play.

Keep us posted... and at least attempt to get the home warranty company to do the right thing... and have someone who KNOWS WHAT THEY ARE LOOKING AT correct the piping.
 
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Old 12-08-13, 02:44 PM
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Are two of the valves HONEYWELL (YELLOW AND RED WIRES) and one of them ERIE (BLACK AND RED WIRES) ?

Get me the model number of the valves...

What you could do is lock that valve in the open position and disconnect one of the black wires.

This way the valve would be open all the time and get heat whenever one of the other zones called for it.

If you don't disconnect one of the black wires, what will happen when the thermostat calls for heat is that it will automatically close when the thermostat stops calling. They will only stay in the 'manual' mode until the power is cycled to them, so you need to disconnect one of the wires.

Would at least get you by until it is repaired.

By the way, if it is an Erie, chances are good that it's only a ten minute job to change the HEAD itself, the brass valve body doesn't need to be changed. Erie calls their valves 'Pop Top' ... for a reason!
 
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Old 12-08-13, 04:08 PM
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Since drawing is one of my minor hobbies, even if you can't get them to do this, I thought I would show you what I would consider the minimum piping arrangement for that boiler system.

Shown is 'primary/secondary' piping with essential service valves.

 
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Old 02-23-14, 07:34 AM
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Hello, OP. What ended up to be the problem and the resolution to your problem? A bad zone valve?

I'd like to hijack the thread, if I may, as I might be having a very similar problem.

I have a Weil-McLain gas boiler with three-zone heating system. The zones are as follows:

main level baseboard heat - zone 1;
second level baseboard heat - zone 2;
main level addition forced air - zone 3;

Second level zone's thermostat always registers temperature at around 4 degrees lower than the temperature setting when calling for heat, i.e. if the temperature is, say, 64 I have to move the thermostat lever on top to close to 70 for a "click" to call for heat! What happens next is really bizarre, I get a shatter or a bang in that zone's pipe! The temperature on the thermostat will never reach the thermostat call-for-heat setting but will shut off when moves, again, within 4 degrees of the call-for-heat setting. Once again, I'd hear a clunk or a bang in that zone's pipe!?

Now, this problem had started to happen shortly after some work had been done on the heating system. The work done was:

- replaced the circ pump (single pump serving all three zones!);
- replaced gas valve;
- water heater replaced;
- zone 2 had air and was bled;

All three zone valves are Honeywell V8043F1036. The pressure in the system is a healthy 25PSI and the temperature is at around 180.

Questions, is it a bad zone valve? Do I still have air in the zone? I can provide pictures of the setup if it may help to pinpoint the issue. My plumber cannot seem to figure this out and he has not been over here since the issue started.

We purchased the house end of summer last year.

EDIT: my plumber had also suggested that I need to have the air separator valve replaced to eliminate the possibility of air in the zone.

Thanks to everyone who may be able to provide any clues to this issue...
 
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Old 02-23-14, 08:01 AM
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Dobroe Utro Igor,

Sadly, the OP never returned after his last post. I'll never understand this behavior... wasting other people's time...

if the temperature is, say, 64 I have to move the thermostat lever on top to close to 70 for a "click" to call for heat
What type of thermostat? Old style with mercury bulb inside? If so, make sure thermostat is perfectly level or the accuracy will be far off.

What happens next is really bizarre, I get a shatter or a bang in that zone's pipe! The temperature on the thermostat will never reach the thermostat call-for-heat setting but will shut off when moves, again, within 4 degrees of the call-for-heat setting. Once again, I'd hear a clunk or a bang in that zone's pipe!?
Yes, could be some affect of air, could be a zone valve installed backward, or something else...

The pressure in the system is a healthy 25PSI and the temperature is at around 180.
IF and only if the gauge is to be trusted for accuracy!

Read this:

http://www.doityourself.com/forum/bo...ure-gauge.html

I would also like you to read this, since it's certain that your plumber hasn't got a clue:

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

I can provide pictures of the setup if it may help to pinpoint the issue.
Yes, please.

EDIT: my plumber had also suggested that I need to have the air separator valve replaced to eliminate the possibility of air in the zone.
Let's see what you've got there before deciding this.

By the way, I'm going to move this to a new thread, since obviously the OP is not going to help you.
 
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Old 02-23-14, 08:10 AM
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Spasibo, NJ Trooper, for a quick response!

The thermostat is indeed the old style with a mercury filled bulb inside.

I am pretty sure, it is leveled as I never touched it and it worked properly early on...

The zone valve being installed backward is unlikely: all of the zone valves are sitting in near proximity with each other and in the same position on their respective return pipes.

I'll snap some photos on my phone, ship them to my computer and upload on here later on today!
 
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Old 02-23-14, 08:22 AM
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Pazhalooysta Igor,

The zone valve being installed backward is unlikely
While unlikely, should be checked. There should be a flow direction arrow cast into the body of the valve.
 
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Old 02-23-14, 08:55 AM
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Interesting about the zone valves being installed backwards, if this, in fact, will turn out to be true!

Here're the picture of the setup:

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The arrow on the valve body points towards the wall! Now, my understanding (and it might be poor) is that the black vertical pipe coming from the boiler is the outlet pipe and the zone valves are sitting on the inlet pipe and that's exactly where the pump is located. This means that the zone valves are, in fact, installed backwards!? If so, how has this system been working all along???
 
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Old 02-23-14, 09:34 AM
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The arrow on the valve body points towards the wall! Now, my understanding (and it might be poor) is that the black vertical pipe coming from the boiler is the outlet pipe and the zone valves are sitting on the inlet pipe and that's exactly where the pump is located. This means that the zone valves are, in fact, installed backwards!?
Yes, the black vertical pipe, the one coming out of the TOP of the boiler is the HOT SUPPLY OUT of the boiler and the one at the bottom with the pump is the cool RETURN TO the boiler.

If those valve arrows are pointing toward the wall then they are all installed backward.

Tupoy installers... or maybe p'yanyy!

If so, how has this system been working all along???
Noisily, with water hammer sounds when one valve closes and another is calling with the pump still running.

If you look at a cross section of these valves you will see a plastic 'ball' that is pushed by a lever against the opening to close the valve. When installed in the proper direction, the ball is pushed AGAINST the flow of water and this cushions the closing. When backwards, the ball is pushed in the same direction as the flow and the ball 'slams' against the seat causing water hammer noise.

Sometimes the ball 'bounces' against the seat and multiple hammer sounds are heard, the first being louder than the second (and sometimes even third).

Sadly, the solution is to have the valves reversed. $$$

While you are looking down there, you might want to check that the PUMP is flowing the proper direction! Although if it were, I expect that the boiler would be making strong complaint noises, it is a good idea to check this as well. Arrow pointing DOWN, toward the boiler.

I thought you would also show the air eliminator that plumber suggested be changed... I DO see the 'air scoop' itself, and these do NOT go bad, but it does appear as if the automatic air vent on TOP of the scoop is, or has been, leaking... so show me that as well.
 
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Old 02-23-14, 09:58 AM
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Agh! Do you think the valves are still good and the bodies can be just reversed or they need to be replaced? I am calling my plumber buddy who installed the pump. The pump appears to be installed properly with arrow pointing down...

I just heard the thump in the valve when the boiler kicked in indicative of the plastic ball hitting the valve opening.

Here is the picture of the air eliminator:

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Tupoy installers... or maybe p'yanyy! - that was funny. Good Russian. are you Russian?
 

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Old 02-23-14, 10:55 AM
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are you Russian?
No, have many friends at my day job though... learn ALL the really good words , you have a very colorful language! I don't know much else! I can count to ten though!

Here is the picture of the air eliminator:
It's hard to tell if the air vent is the one that leaked and caused all that rust (it was leaking a LONG time!) or if it's been replaced... it appears that it has [been replaced].

If the air vent has been replaced, then as long as the small cap on top is loose to allow the captured air to vent, and it is not leaking with the small cap loose, then all is well there. That type of air scoop does not go bad... no moving parts.

I am calling my plumber buddy
Ooops! Didn't realize he was your buddy! Please don't tell him that I said he "didn't have a clue!", I meant it in the nicest way possible!

I still recommend that you check the gauge accuracy and service the expansion tank when you get a chance. Maybe ask your buddy to install the optional valves to make servicing the tank in the future easier?
 
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Old 02-23-14, 04:49 PM
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Yeah, Russian is a colorful language, indeed...

My plumber friend was the first one who pointed out how ass backwards the piping was done in this system: he had fixed things as they went bad but we never really looked at the zone valves. They seemed to have been doing the job, he was able to bleed the system, thermostats call for heat, there's flow so no problem. Only when I mentioned to him that the valves show that they were mounted backwards did he suggested that we re-pipe the setup and make it more efficient.

We agreed that he'd do it when it gets warm so we can shut the system off and overhaul it then.

I guess, I can live with an occasional banging of the pipe in that zone so long as there's no harm done to the boiler and the valves.

Also, he brought up a thread on here where this issue is discussed. It is suggested in the thread (you appear to be contributing to it as well, it is from a year or so ago) that these particular Honeywell valves could cause the water hammer and are easy to install backwards without really noticing any ill effects...

It is also discussed that there's a short spring(?) that can be disconnected to allow a slower closing of the valve and prevent the hammer. Not sure what that spring is. I guess, it is from the lever on the electric side?
 
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Old 02-23-14, 05:11 PM
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Here is the topic I was referring to...

http://www.doityourself.com/forum/bo...ne-valves.html
 
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Old 02-23-14, 05:17 PM
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Also, he brought up a thread on here where this issue is discussed.
Oh no! You mean he read himself what I said? My apologies Mr. Plumber Buddy!

It is also discussed that there's a short spring(?) that can be disconnected to allow a slower closing of the valve and prevent the hammer. Not sure what that spring is. I guess, it is from the lever on the electric side?
The springs are what close the valves when the thermostat stops calling. There are two, and the theory is that removing one will cause the valve to close more slowly, but honestly, I don't see the point... if the valve is installed properly, there shouldn't be a problem at all.

The newer style valves, the 5000 series (basically the same thing as the series 1000 that you have but with a redesigned power head) are said to be better in this regard and may have only one spring? I've not 'dissected' one so don't know what the real differences are.
 
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Old 02-24-14, 05:26 AM
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Yep, no one seems to be very familiar with these zone valves (old?). I popped the cover off one and I see two springs holding the head of the valve from the opposite sides. I can see how removing one will allow for a softer operation but I won't be messing with it.

We now know what the problem is, and as I mentioned, the piping and design of the system needs to be changed.

You've been a great help, Trooper! Great forum too!
 
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Old 02-25-14, 10:49 AM
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The cap on the air eliminator is actually not floating loose. It is kind of caked in. Sounds like I might need to replace it. Is it as simple as shutting the boiler off to eliminate pressure, unscrew the old one and screw a new one on?
 
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Old 02-25-14, 01:29 PM
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Is it as simple as shutting the boiler off to eliminate pressure, unscrew the old one and screw a new one on?
Yes, more or less... but there is a bit more to eliminating the pressure than simply shutting off the boiler.

You also need to shut off the water supply to the boiler, and then open a drain valve to relieve the pressure in the boiler to zero.

You should not need to drain the boiler as long as you can work quickly. Have the new vent at hand and unscrew the old one with a 'thumb' ready to plug the hole so you don't make too much of a mess. Get new one ready and move thumb and screw it in.

While you have the boiler pressure to zero, check the air charge in the expansion tank...
 
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