Mystery 101: furnace at 35 psi and I don't know why!

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  #1  
Old 08-29-14, 06:22 AM
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Mystery 101: furnace at 35 psi and I don't know why!

Without giving you too much history...
- Oil-based heat; furnace at 35 psi
- brand new pressure relief valve (no water comes out until 33 psi, trickle of water at 35 psi)
- brand new boiler feed valve (factory set 14-17 psi)
- brand new expansion tank charged at 13 psi
- dripping spirovent microbubble absorber atop expansion tank
- well water with some crud in it

Furnace has a MAWP of 50 so I'm not freaking out at the moment (unless you tell me otherwise).

When I manually release water from the PRV, water squirts out of the spirovent (not sure this is relevant).

Question: any thoughts on how to determine the source of the high pressure?

Question: can I service the spirovent and is that related to the high pressure? (the spirovent is >$100 and I would need to cut pipes, so I want to service it but am not sure about that)?

Photos below. Let me know if you have questions. I truly appreciate any guidance or suggestions.

Paul

http://i1371.photobucket.com/albums/...ps13c49eb4.jpg
http://i1371.photobucket.com/albums/...psf2edabc2.jpg
http://i1371.photobucket.com/albums/...ps0cb4e17b.jpg
http://i1371.photobucket.com/albums/...ps21843911.jpg
http://i1371.photobucket.com/albums/...ps9680f6b6.jpg
http://i1371.photobucket.com/albums/...psf39f2824.jpg
 
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  #2  
Old 08-29-14, 06:48 AM
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Hello and welcome to the forums...........

Did you set the water pressure to 12 psi then shut off the water feed? Could be the pressure reducing valve is faulty. And if you have the water off and it still rises the valve my be shot and not holding closed.

Next that boilermate may have a leak internally and house pressure is getting into the boiler side. You could test buy turning off the cold water valve to the boilermate and reduce the psi in the boiler. ( Dont use any water in the home while doing this test ) See if the pressure goes up..

Just for giggles what the well tank psi read?


Next loosen the air vent cap here and leave it loose. If it leaks tighten it back up.

Let us know how these tests go................

 
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Old 09-02-14, 04:06 AM
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Hi lawrosa,

Thanks for the welcome, and sorry for the delay.

I am setting the water pressure by draining off some water from an upper heating loop. It doesn't seem to be that accurate so tell me if I should do it another way.

I repeated the following process twice:
- Shut off water feed
- Shut off cold water to hot water heater
- Set psi at 12
- Opened water feed
Pressure popped up to 17 and stayed at 15-17 overnight

I also repeated the following process twice:
- Shut off water feed
- Shut off cold water to hot water heater
- Set psi at 12
- Opened cold water feed to hot water heater
Pressure dropped to 0 over 4 hours

The only way to get up to the dreaded 36 psi is with both incoming water and cold water to hot water heater open. I could start guessing but I'll let you tell me what all this all means!

Well pressure is 45 psi. The air vent is moving freely and has a drop or two of water on it.

Thoughts? Thanks!
 
  #4  
Old 09-03-14, 05:19 PM
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It's one of 2 things. Hole in the coil of the indirect or feeder is over feeding. The easiest way to tell if the indirect is to put a pressure gage on the cold water drain on the tank. Now hopefully you have ball valves on the hot and cold side of the tank. If you do put the gage on the drain and open it then shut off both valves. It should start around 60 or whatever the street pressure is. If there is a hole the pressure will slowly go down. If you don't have a valve on the hot side this isn't going to work. You will have to run the BOILER (not furnace) for the amount of time that it would usually take for the pressure to go up. If the tank is off and the pressure stays normal then it's your tank. If the pressure still goes up then it's the feeder. Might not be a bad idea to check the expansion tank as well. Just because something is new doesn't mean it's working properly.
 
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Old 09-04-14, 04:53 PM
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Dburr9,

Thanks so much. I attached the pressure gauge to the cold water drain (40 psi) and then shut the other two valves. I left it for 30 minutes and there was no change in pressure. I'll leave it and check again.

That leaves the "feeder over feeding." I don't know my ass from my elbow but I'll do my best. Directly feeding the furnace is the feed water pressure regulator. Because of this psi problem, I replaced it a week ago so it is brand new. Maybe it's still the problem. Before the feed water pressure regulator I have a pressure reducing valve. The PRV failed on me about 8 years ago. Could it be the PRV or am I barking up the wrong tree? PRV photo below.
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If the PRV is irrelevant, then it's down to:
- the new expansion tank
- the new feed water pressure regulator
- the leaky spirovent on the expansion tank
- the air vent after the presure regulator

Thank you again! I like working through this. The funny part is how irritated my wife is getting - this will teach her to take "water on demand" for granted.
PFlax
 
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Old 09-04-14, 05:03 PM
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Before the feed water pressure regulator I have a pressure reducing valve.
Count me as confused...

'feed water pressure regulator' and 'pressure reducing valve' are the same thing, no?

Is that picture BEFORE you replaced it? Looks to me as if it's leaking?
 

Last edited by NJT; 09-04-14 at 05:26 PM.
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Old 09-04-14, 05:06 PM
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Here is your water feed/reducer and backflow preventor... There is a valve somewhere before the back flow preventor.. Shut off the boiler feed and drain the boiler to 12 psi. Leave valve closed and run system normally.

Let us know..



Here is another.... Where is this???? Is this for the main water to the home I would assume?




The expansion tank on left needs to be tested from the schrader valve. Should have 12 psi


[ATTACH=CONFIG]37680[/ATTACH]



Can you show a pic of that tank??? You dont have an xtrol filltrol like this do you? ( Below pic) If not then the way to test the pressure is with the tank removed, or 0 psi on the boiler so there is no pressure on the tank when taking a pressure measurment...




Amtrol- Fill-Trol

 
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Old 09-04-14, 06:00 PM
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I've seen pressure reducing valves on the water main but not right in front of the boiler.
It might be time to call a service company. You don't want to keep draining the boiler and you don't want it running anywhere near 30 psi. If it's all brand new and it's still over pressurizing I'd just get it looked at.
Even though the info you've given has been good its hard to diagnose without standing in front of it.
 
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Old 09-05-14, 05:22 AM
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NJ Trooper, here's the overall flow. The pressure reducing valve (Watts box says "Pressure Setting 1/2 50 psi") sits right after the well tank, then the filters, and then the pressure regulator that is factory set to feed at 14-17 psi. It seems the PRV is an added level of protection?
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Here's a full picture of the expansion tank with the dripping spirovent. With system pressure at 0 this morning, I tested the expansion tank and it is at 13 psi.
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Per lawrosa's note, I shut the boiler feed and drained the boiler to 12 psi. It is holding steady at 12 psi. This tells me the problem is somewhere in the chain that feeds the boiler, right? Where in the chain is the next question.

Per dburr9, I am draining/filling and I am running it at 35 psi to shower, etc.

Suggestions?

Thanks to all.
 
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Old 09-05-14, 06:01 AM
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OK, I think I understand the confusion now.

MOST well water systems do not have nor require a pressure regulator after the well tank. The domestic well water pressure should be regulated by the PRESSURE SWITCH on the well pump which is typically set at 40 PSI 'cut in' and 60 PSI 'cut out'. These numbers could differ depending on the condition of your well and pump. Could be lower or higher, but typically 20 PSI apart.

So for some reason someone installed a pressure regulator on your domestic well system.

It actually has NOTHING to do with your boiler problem. If the pressure in the home on the domestic is OK, then just forget about everything to the left (in your diagram) side of the 'feed regulator'.

You don't show it in the diagram, but the rest of the domestic water piping for your home should be branching off the pipe between the 'in line filters' and the 'feed regulator'.

Per lawrosa's note, I shut the boiler feed and drained the boiler to 12 psi. It is holding steady at 12 psi. This tells me the problem is somewhere in the chain that feeds the boiler, right? Where in the chain is the next question.
If closing the manual shut off feed valve to the boiler has stopped the pressure rise, it means that the only place the problem can really exist is in the pressure reducing valve... which I believe you said is NEW?

What happens too often is that there is some 'crud' in the water lines that doesn't get flushed out before installing the new reducing valve. This crud gets into the new valve and turns it into an expensive paper weight.
 
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Old 09-05-14, 06:19 AM
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Wow, this forum and you guys are great.

NJ Trooper, I understand the points you made and that anything to the left of the pressure reducing valve is unrelated to my boiler problem. Yes, the rest of the house water branches off.

I'm going to get a new pressure reducing valve and, this time, I'll flush the pipes before installing it.

I'll report back over the weekend.

Thanks again!
 
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Old 09-05-14, 07:03 AM
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Why dont you try to adjust it first????

Sometimes lifting the top handle a few times flushes it out..

It may take some time to adjust.. Drain, fill...check psi, adjust... repeat...



http://media.wattswater.com/1910265.pdf
 
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Old 09-05-14, 07:05 AM
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Also clean the strainer................
 
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Old 09-05-14, 08:25 AM
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Will do - I'll try and clean this one out first and I understand that lifting the handle a few times might help flush things. Will check any screens too.

Thanks.
 
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Old 09-05-14, 08:37 AM
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And I linked the instructions in case you have not seen them....... Turn rod CCW to reduce psi as stated....
 
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Old 09-05-14, 09:10 AM
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I don't think there's any point in attempting to adjust the valve.

If it's raising the pressure that high, then it's not an adjustment issue. They don't just spontaneously go out of adjustment. They may very slowly creep out of adjustment over the course of years from the spring tension changing... but a brand new valve isn't going to change from 15 to 30 PSI all by itself.

No, if that's happened, it's because the valve is leaking through... unless someone has already fiddled around with the adjustment and it's all caddy wompus now.

Your SpiroVent leaking is most likely an UNRELATED and SEPARATE issue. It may be leaking MORE with the higher pressure behind it, but it will still leak with the lower pressure.
 
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Old 09-06-14, 11:44 AM
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Still at a loss here. Installed brand new pressure regulator feeding the furnace. No change. psi up to 36.

Shut incoming water supply and dropped pressure to 20 psi, and pressure stays at 20 psi.

Earlier tests indicated the boilermate is not leaking water back into the system. I repeated/confirmed them.

So, the problem is on the feed side but the new pressure regulator(s) don't seem to be doing the job. Can a person screw up installation? There's nothing to do except make sure the dang arrow is pointing towards the boiler, right?

I guess I gotta find a plumber, although I'll check back if anyone has questions or suggestions.

Thanks,

Paul
 
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Old 09-06-14, 11:53 AM
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Quick update. I fiddled and diddled with the feed valve toggle and it seems to (maybe) be stablizing at around 17 psi. I'll report back later but I wanted to send this before you give to much thought to my prior message. Thanks. More to come.
 
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Old 09-06-14, 12:00 PM
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I don't think I was on-board early in the thread...

Did anyone suggest that the gauge may be bad?

Read this:

http://www.doityourself.com/forum/bo...ure-gauge.html
 
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Old 09-06-14, 12:32 PM
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Did anyone suggest that the gauge may be bad?
And are you reading psi on the gauge? The other #'s are ft h2O. ( I have done that many times..)


 
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Old 09-06-14, 12:56 PM
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Update: pressure built back up to 35. I dropped the pressure to 10, listened at the feed valve and I could hear it stop filling at 12 psi and then the pressure keeps going up without any audible sound of water at the valve.

I'm definitely reading psi and I considered the idea of a faulty gauge, but the fact that the pressure release valve starts dripping water at around 30 psi seemed to confirm (to me) that the gauge was OK. Thanks for the link on this - I attached my small gauge to a drain and it confirms the 30+ psi.

It seems there might be a source, other than the main feed or a leak in the water heater, that is pumping up the pressure? Is that possible?

Thanks for hanging in there, guys.
 
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Old 09-06-14, 01:46 PM
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I assume the boiler is running to heat the indirect correct?

What is the temp of the boiler?

Also what well pressure do you have again?
 
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Old 09-06-14, 01:48 PM
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Its either the fill valve.. Which it appears we ruled out..

The indirect, that am not sure if thats ruled out..

Or no or low pressure in the expansion tank... The pressure would rise due to this when the boiler gets hot...

Let us know...
 
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Old 09-06-14, 02:22 PM
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A lot of times the feeder will slowly over feed. It will stop at its set point but then over the course of a few hours it will let water in. You said the expansion tank was at 13 psi so we can eliminate that. I would pressurize the boiler then shut the water off. Let it run fir a few hours. If after a few hours the pressure is normal than its your feeder. Do the same with the indirect. Shut off the cold water in (you won't have hot water) . It's gotta be one of those 2 things.
 
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Old 09-06-14, 02:29 PM
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You said the expansion tank was at 13 psi so we can eliminate that.
Only if its being tested properly... All pressure needs to be removed from the boiler to test. Or remove the expansion tank..

Do the same with the indirect. Shut off the cold water in (you won't have hot water)
But you need to be careful here and use no water in the home.. If you use a single lever faucet the cold water will back through the hot line back to the indirect and pressurize it... Hence raising the PSI in the boiler if there is an issue..

To the OP.. You have to be more systematic with your tests if you want to find the issue..

Seems we have been around the block a few times already....
 
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Old 09-06-14, 02:57 PM
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Fair enough comment, lawrosa. I'm big on hustle but some brains map well to plumbing issues and some don't.

I'll take each of the three possibilities (Feed, Indirect, Expansion tank) and, with patience, test each one according to your suggestions. Tomorrow. For now, it's Miller Time.

Thanks again all. If I was standing next to you, I'd buy you a cold one.
 
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Old 09-06-14, 03:11 PM
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For now, it's Miller Time.
Same here.....

 
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Old 09-06-14, 03:35 PM
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All pressure needs to be removed from the boiler to test. Or remove the expansion tank..
I believe he did say the boiler was at zero when he checked and found 13 PSI in the tank.

Was there any WATER out the Schrader valve on the tank when you checked the pressure?

I have had well tanks that the pressure tested fine, and didn't work properly. What happened is that there was WATER on the AIR side and even though the pressure was zero on the water side, they had WATER PRESSURE on the AIR side... because the water had no way out.

Well tanks are a bit different because they're installed with the air valve on top, and yours is installed properly with the air valve on bottom... and that's why I asked if you got any water out.

BY THE WAY... for safety sake...

If you DO remove the tank, be aware that it may be full of water, and BE PREPARED for it to be HEAVY! It won't feel heavy when you unscrew it... even if it is full of water. So understand that you do not want to hurt yourself and drop it on your foot!

Sorry guys, I'm an expensive date... make mine a Sam Adams please!
 
  #29  
Old 09-09-14, 03:29 AM
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Sam Adams! That's no problem.

It was the water heater leaking back into the furnace. I got a guy here, at my wife's insistence. I was a bit too stubborn about fixing it myself and ended up going around in circles and taking you guys with me.

New water heater, new spirovent, replacing the backflow preventer as it is now dripping. Don't ask the damage.

I learned a lot including there are only three possibilities when it comes to pressure that is too high: the feed regulator, the expansion tank, and the hot water heater. I also learned, from the plumber, that those amtrol water heaters develop leaks a bit too often, especially on well water.

Thanks all. Truly appreiate your help. Have a great autumn.
 
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Old 09-09-14, 04:14 AM
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New water heater,
Thanks for sharing this info that its all good now..

Just curious as to what heater did you get?
 
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