Oil Heat Problem. Heat won't shut off in zone!!

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Wow!
And thanks for the feedback!
 
All sounds sensible. And sounds like your water is corrosive.
 
Bartsfam,

Something I would look into is why your system had zero water pressure... Where did it all go? Have you had any leaks recently? Did the tech that worked on it last time not let it fill back up? With a closed system, you should only need to fill the system once, and once the air is purged, you really dont need to add any more water to it.

I also have a cold-start oil boiler, and its normal for it to get cold like that when no zones call for heat.

Is your problem all fixed, or is that one zone still acting up? I just wonder why if it was steam that it wouldnt impact all three zones, since I wouldnt think that it would be selective like that.
 
Hi;

I believe that he said that he thought that it over heated a couple of times, and the expansion tank relief pipe did have water coming from it, so maybe that was why there was water missing.

He also had to drain and refill the pipes because he said there was a lot of air in the system.
As for the steam going to a certain zone, he did replace one of those relief valves (vent?) that I posted previously, which he said allowed the steam to go to that particular zone.
Ever since he did what he did, everything is fine, with no heat going to that zone.

One more thing about our "cold start" systems...of course he said that this was bad way to have your boiler set, because it forms alot of condensation in your boiler, leading to more rusting and corrosion.

He wanted to sell me a new aquastat, that has an outdoor sensor so it keeps your boiler more in tune with the weather. It costs $500, but he said there was some type of rebate for $225.
 
I guess if you had a bad air vent and a bad fill valve, if you were a little low on water, when your system cooled down, it could suck air in, and then when heating up spill some out.

Im no rocket scientist, but it just seems strange that a bad vent would allow steam in one pipe, but water to stay in the other three... Then again, if its working now, then not a problem.

Cold start systems can get condensation when they first fire, which is why it wouldnt be good to short cycle them. But they are a low-mass system so they heat up quickly to burn off the condensation. You just want to be sure not to cycle them at low water temps.

The outdoor air reset is a good idea, but only if your distribution system can still provide heat to your house at lower water temps. What it does is adjusts the aquastat based on the temps outside. On the really cold days, it goes up to 180 or 200. Mild days it will take it down to 140 or 150. If there is a rebate, might not be a bad idea, given the price of oil these days.... However, given the above listed issues with the valves, I would look into a water treatment system / softener for your house/boiler feed.
 
seige101 said:
Sounds like you need a check valve on the system to prevent thermo siphoning. This would prevent the warm water from thermo siphoning, but when the pump kicks on it would open and the water would flow freely.


+1 I just put in new oil boiler with cirt's for each zone and found that when any of the cirt's were running hot water would go to least restence and cirt. It ended up I needed to put check valves in each loop now all fine, it was a pita to cut into each loop but did the trick.
 
seige101 said:
Sounds like you need a check valve on the system to prevent thermo siphoning. This would prevent the warm water from thermo siphoning, but when the pump kicks on it would open and the water would flow freely.

X2 but it should be a "Sweat Check" valve not just a check valve on the supply side of the zone to prevent the heat from convecting!!!

See pic below of My Sweat Check valve
 

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Hello All Again!!

I am the original poster, and unfortuantely another problem. The boiler didn't even last a month!!

I woke up on Saturday morning, and found a good size puddle of water underneath the boiler. I mopped it all up, and woke up this morning and was greeted by the same thing!

This water is coming from underneath the boiler, and not the downward facing pipe. As previously posted, less then a month ago, I spent close to $600 on all new valves, and now this!!!

From what I can tell, the water only leaks when the boiler kicks on, and the water is cold to the touch.

Anyone have any ideas? It looks bad to me.
 

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Well, if its not coming from your overflow valve, that means its not the temperature/pressure relief valve.

I would say to stand near the boiler, then have someone kick on the thermostat for you so it runs. Then you can see where the leak is coming from. If it only happens when its running, it could be that one of your zones has a leak in it, and it only leaks when the circ pump runs to pressurize that joint further.

I hope its not your boiler leaking, since that would definitely be a bad deal....

Regardless, I think you need to look into some water treatment just to make sure you dont crud up your new valves!
 
I did what you said.

When facing the boiler, the water is leaking from underneath the left side. The water coming out is cold, but the boiler is on. It seemed to leak out after the boiler shut off though. Once it was off, the pooling began from underneath that left front side.
 
Give this a shot...

Turn off the makeup water connection to your boiler, then cycle it again, and see if any water then leaks out of it. What side is your boiler expansion tank on? Do you have a pressure gauge on your system? Does it move alot between when the boiler is on and off?
 
Clarkbug said:
Give this a shot...

Turn off the makeup water connection to your boiler, then cycle it again, and see if any water then leaks out of it. What side is your boiler expansion tank on? Do you have a pressure gauge on your system? Does it move alot between when the boiler is on and off?

It could be coming from your backflow prevention device on your make up water.
 
"make up" water is the connection from your domestic cold water piping in the house to the heating system. There is usually a pressure reducing valve on it (looks sort of like a bell with a screw on the top and a lever on the side of it).
 
I did what you said. I shut off the make up water. I then started the boiler. It still leaked, but the water that leaked this time was very warm, to almost hot. Before it was cold. I got nervous, and turned the make up water back on...

Also, no great jump in pressure. It strayed between 40-60.
 
40 to 60!

Woah Nelly!

Most boilers have the pressure relief set for 30 PSI...

But the fact that it was leaking regardless isnt a good sign. It might be time to call someone in to take a look at it, or if you are comfortable with it, take the sheetmetal skin off of that side and look to see if something looks awry...
 
You know....I think I read the pressure gauge wrong. I was reading the bottom numbers below the line, which made them 40-60. When I read on top of the line, it was right at 30. Below the line has a different set of numbers.
But...regardless, I'll have to call the plumber tomorrow and see what he says.
 
Good luck with it, and please post back with what you find! Sorry to not be of more help.... Just hard to do via keyboard :/
 
Well....I think I dodged a bullet.

It was the boiler pressure relief valve. I did not see it, but way in the back, on the bottom right, was this relief valve, leading to a downward facing pipe.

That was where the cold water was coming from, I just did not see it yesterday, as it is in very tight quarters. The water was tricking out of the pipe, and then going underneath the boiler and puddling in the front.

TOTAL COST: $337

That's about $900 in servicing on a boiler that I barely use, in one month!!
 
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