Boiler help - pressure release constantly triggers; no heat

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Certainly sounds that way.
You shouldn't be messing with the regulator not knowing what you are setting it to.
It's a good thing the pressure relief valve is working.

After you get a reliable pressure gauge i strongly suggest you do what fixitron suggested in post #8 above. i.e.- make sure the expansion tank is set up correctly and doesn't have a ruptured bladder.

Edit: Assuming it has a bladder.
 
Other similar threads concerning pressure relief valves have suggested flushing the valve, by opening it fully in a few short bursts.
To release grit that might be causing it to not seal properly.
Also, other suggestions have been that a few gentle taps on the relief valve might help it to fully seal.
You can find more info if you search this site.
 
In the photo that you posted, the cap on top of the PRV is missing. It has a lever to push that pin down and fast fill the system. Screwing in the threaded portion changes the set pressure and if your gauge isn't moving when you feed water then there is another issue and you no longer know what pressure the PRV is set for. Get that cap and use the lever to feed water manually.

If all of those parts you noted are new, there is something else going on. I would start with replacing the Tridicator (pressure/temp. gauge). For the interim, you could use a screw-on hose attachment with a pressure gauge, and yes you can get them with a 0-100 psi gauge or smaller range.
My next thought is that maybe the expansion tank is too small? Do you have a LOT of piping (water volume) in your system? Does your piping go higher than 3 stories?

If this has been happening every winter since you moved in, I am suspecting a design/installation problem and not a failed part. If for some reason your feed water was plumbed to enter the system after the air eliminator (strainer + auto air vent, or Spirovent), it would not have a chance to eliminate any air that comes out of solution out in the system.
As with trying to solve any of these problems, the more information available, the better. Pictures tell a lot as well (such as photos of the boiler and associated piping around it).
 
In the photo that you posted, the cap on top of the PRV is missing. It has a lever to push that pin down and fast fill the system. Screwing in the threaded portion changes the set pressure and if your gauge isn't moving when you feed water then there is another issue and you no longer know what pressure the PRV is set for. Get that cap and use the lever to feed water manually.

If all of those parts you noted are new, there is something else going on. I would start with replacing the Tridicator (pressure/temp. gauge). For the interim, you could use a screw-on hose attachment with a pressure gauge, and yes you can get them with a 0-100 psi gauge or smaller range.
My next thought is that maybe the expansion tank is too small? Do you have a LOT of piping (water volume) in your system? Does your piping go higher than 3 stories?

If this has been happening every winter since you moved in, I am suspecting a design/installation problem and not a failed part. If for some reason your feed water was plumbed to enter the system after the air eliminator (strainer + auto air vent, or Spirovent), it would not have a chance to eliminate any air that comes out of solution out in the system.
As with trying to solve any of these problems, the more information available, the better. Pictures tell a lot as well (such as photos of the boiler and associated piping around it).

So yes, I have the pin and the cap w/ lever on it. It's just not pictured here because I had removed it to screw the threaded portion down. Plumber-in-law says that fast-filling the system will blow the pressure and cause problems, but slow-filling it doesn't seem to be working either.

This morning the floor was covered with water due to the pipe coming from the pressure release valve. It was flowing like a spigot that had been lightly turned on - much more than a drip. While this was happening, the Tridicator read 20 PSI. I assume it had been dripping most of the night and this morning I had very little/weak heat on 2nd and 3rd floor.

Even last night after I got water all the way to the top of the system, i took maybe 4 hours for the 2nd floor thermostat to go from 60 to 66 degrees. And it wasn't that cold out (maybe 30-40 degrees). I think I'm getting low-pressure, air-filled heat upstairs from more or less the moment I successfully refill the system each time.

Expansion tank was just replaced last year with a bigger size. I wouldn't say we have an inordinate amount of piping. Home is 4 floors (though top one is just a sort attic/bulkhead but there is piping up there). About 3000 sq feet total.

Also my house is adjacent to a home (city living) that was built at the exact same time and the framing/plumbing of which should be identical. I'm going to ask my neighbor if I can have a look at his boiler room to compare.
 

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The fast fill feature of a PRV is not meant to be used on a closed system with just an vent open.
It is meant to be used for initial quick fill and/or purging of air. A drain hose should be connected to a drain valve on the zone being purged, constituting an open system which will get rid of the majority of air. The recommended air vents are still required in their respective locations.

Although 12 psi may me the typical pressure setting, it is not for every application. Watts recommends 3 psi at the highest point in the system. In fact their S1156F unit comes factory set at 15 psi. Typically adequate for a 3 story building.

You should determine the total height from your new pressure gauge to the highest point in your system. To convert the height in feet to psi simply divide the feet by 2.13. (1 psi = 2.31 feet of head) Once you determine the minimum psi to get you to the highest point of the system, ADD 3 psi. Chances are your required psi setting will be a bit higher than the typical 12 psi.

As previously mentioned get a gauge that is working properly. Check your expansion tank and adjust air pressure to match the new pressure setting of your system. Not 12 psi. And of course that air pressure is added when there is no pressure exerting from the water side.

I believe fixitron was hoping for additional pictures of the entire setup in the basement. Showing relative locations of all components, including air vents, air scope, zoning arrangement, etc.

Once things get squared away, individual purging of each zone, with an open drain valve on that zone, can be done.

EDIT: If you're not familiar with the proper procedures for adding air to your expansion tank or purging the air through each zone, there are numerous videos on the web covering that stuff.

It sounds like your plumber father-in-law may take different approaches. Watch more than one video on any subject as these guys do vary in their thinking.
 
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The fast fill feature of a PRV is not meant to be used on a closed system with just an vent open.
It is meant to be used for initial quick fill and/or purging of air. A drain hose should be connected to a drain valve on the zone being purged, constituting an open system which will get rid of the majority of air. The recommended air vents are still required in their respective locations.

Although 12 psi may me the typical pressure setting, it is not for every application. Watts recommends 3 psi at the highest point in the system. In fact their S1156F unit comes factory set at 15 psi. Typically adequate for a 3 story building.

You should determine the total height from your new pressure gauge to the highest point in your system. To convert the height in feet to psi simply divide the feet by 2.13. (1 psi = 2.31 feet of head) Once you determine the minimum psi to get you to the highest point of the system, ADD 3 psi. Chances are your required psi setting will be a bit higher than the typical 12 psi.

As previously mentioned get a gauge that is working properly. Check your expansion tank and adjust air pressure to match the new pressure setting of your system. Not 12 psi. And of course that air pressure is added when there is no pressure exerting from the water side.

I believe fixitron was hoping for additional pictures of the entire setup in the basement. Showing relative locations of all components, including air vents, air scope, zoning arrangement, etc.

Once things get squared away, individual purging of each zone, with an open drain valve on that zone, can be done.

EDIT: If you're not familiar with the proper procedures for adding air to your expansion tank or purging the air through each zone, there are numerous videos on the web covering that stuff.

It sounds like your plumber father-in-law may take different approaches. Watch more than one video on any subject as these guys do vary in their thinking.

This is really helpful. Thanks very much. Plumber-in-law was there all day today and says he's got it working. I'll take a look at the situation when I get home from work and upload relevant pictures if need be! Thanks so much to this community. It's been a real source of sanity.
 
We need to see a complete picture of all the piping at the bolier. This should include the circulator pump, expansion tank, water feeder, etc. I need to see the relationship of the pump to the tank the water feeder. Also put a water pressure gauge on one of the purge station drains to get a boiler pressure reading.
 
This is really helpful. Thanks very much. Plumber-in-law was there all day today and says he's got it working. I'll take a look at the situation when I get home from work and upload relevant pictures if need be! Thanks so much to this community. It's been a real source of sanity.
Ask him what pressure the system is set for. Or better yet look what the pressure gauge is reading. Assuming there is a working pressure gauge there.
 
The way I was taught to remove air from radiators in a multi-story house was to work from the bottom up. Get the air out of 1st floor radiators, then 2nd floor, then top floor.
Working only from the top, lower floor radiators *will* retain air - not good!
Automatic air-valves are great; I remember buying some that worked using multiple tiny sheets of paper, swollen with water they held pressure (closed the valve), with low water in radiator, paper dried up, and opened the valve. KISS. ... Eventually this variety of automation would fail -- mineral build-up.

However, you mentioned in 1st post that the system has 3 zones.
Questions: Is each zone a full floor, or a portion of the house, or what?
In addition, how does zoning work - One circulator, plus 3 thermostat-controlled solenoid-valves, one for each zone?, or, Three separate circulators, and a thermostat for each zone?, or, some other design?
If solenoids, are the valves normally open, or normally closed, in other words, how do you make sure the whole system is being bled, or are you just bleeding air from one zone?

Lastly, water only has a fairly small percentage of air in it, if your system keeps filling with "air" you're losing water somewhere. Try putting a 5-gal bucket to catch what the blow-off valve is doing. If there's not much there, you've got a leak *somewhere*.
.
 
An update here: it seems like the (new as of last year) release valve was the problem (comparison photo attached). We put on a valve that is rated for 60 PSI (instead of 30 like the old one). System is now fully pressurized with water throughout the house and is generally sitting around 30 PSI. So maybe what was happening was the that the system needed 30ish PSI to heat the whole house and that was constantly blowing the 30-PSI release valve. Since bleeding/draining the system we've had no issues and the pressure has sat steady at 30 PSI.

As luck would have it, my water heater kicked LITERALLY the morning after we go the boiler problem solved! So the water heater pictured here is a brand new one too.

Rains, pours, etc. Let me know if anything looks weird with the setup? We have one pump, 3 zones (basement apt, 1st floor, 2nd/3rd floor).
 

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What are you basing this statement on?
"System is now fully pressurized with water throughout the house and is generally sitting around 30 PSI"
Is you pressure gauge on your boiler working now? What pressure is it reading?

I don't doubt that the system needed more pressure, as we were eluding to earlier. i.e. A few psi above the highest point in the system. But I do doubt it needs 30 psi.

What is the maximum working pressure of the boiler, as stated on its label? (Max. W.P.)

I hope you guys know what you are doing.
 
Does the pressure go any higher when it is heating up the house. The existing pressure relief valve is set to blow water at 30 lbs
so what happens and it does if the fill valve sticks open with debris and keeps filling that boiler. At 60 lbs someone could get
hurt if that boiler would break at the sections with that much pressure on it. Just a thought.
 
Yeah that's a no-go that's like if a breaker keeps on tripping and you just replace it with a larger breaker..... there's obviously an underlying problem here placing the relief valve of one that has a higher rating is not the correct answer but power to you
 
What are you basing this statement on?
"System is now fully pressurized with water throughout the house and is generally sitting around 30 PSI"
Is you pressure gauge on your boiler working now? What pressure is it reading?

I don't doubt that the system needed more pressure, as we were eluding to earlier. i.e. A few psi above the highest point in the system. But I do doubt it needs 30 psi.

What is the maximum working pressure of the boiler, as stated on its label? (Max. W.P.)

I hope you guys know what you are doing.

The pressure gauge on boiler is working, yes. It's reading 30 PSI right now. The system needed more pressure for sure, as you say. I will check the Max W.P. when I get home. I might try to get the pressure down to 25 PSI and see if it's still warm up at the top.

House is approximately 42 ft high with about 3000 sq feet total between all floors. Though the top 3rd floor is technically storage - it's a little peaked attic space, but finished - and it does have about 8 feet of baseboard heat along one wall.
 
Yeah that's a no-go that's like if a breaker keeps on tripping and you just replace it with a larger breaker..... there's obviously an underlying problem here placing the relief valve of one that has a higher rating is not the correct answer but power to you

I don't think it's a question of overdoing it. I think the old valve was bad and just not letting the system get over 10-15 psi. Although we put no a release valve with a higher rating (60 psi), I think it would still be working fine with a new 30 PSI gauge. You can see the photo fo the bad valve. In other words, the higher-PSI valve fixed the problem but not because it was 60 PSI, but because it was new.
 
I don't think it's a question of overdoing it. I think the old valve was bad and just not letting the system get over 10-15 psi. Although we put no a release valve with a higher rating (60 psi), I think it would still be working fine with a new 30 PSI gauge. You can see the photo fo the bad valve. In other words, the higher-PSI valve fixed the problem but not because it was 60 PSI, but because it was new.

Then take off the 60 psi valve, put on a new 30 psi valve to replace what was there, which will be safer to operate.

Less likely to blow a seam somewhere or burn someone with hot water shooting out.
 
A common water boiler is rated for 40 psi and is required not to exceed 30 psi pressure. Hence the reason why 30 psi Pressure relief valves are required.

42 feet is equal to about 18 PSI. Which would then want a 3 psi added to that. Say 22 PSI.

However, the height should be based on the vertical distance between the gauge and the highest point of the system.

Unless your boiler is rated for 70 psi or higher, replace that 60 psi relief valve immediately.

EDIT: Based on earlier discussion I would double check your pressure with a second gauge. Screw it on one of those zone drain valves. The lower the pressure range of the gauge the better. I wasn't able to find any below 200 psi but someone I believe said there were available down to 100 psi. The square footage doesn't matter.
 
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