Utica boiler

scubashack

I have a Utica boiler that tripped its rollout switch! The serviceman told me the length on the exhaust pipe is too long and no pitch!! He lowered pitch checked pipe for blockage but not the chimney, it tripped again!! Now the dampener was left open and front cover off as temp. Fix! I think they just wanna sell me a new system as they told me my current system isnt vented properly! Any ideas? I checked the chimney cap, everything is still in place, no signs of any animal intrusion!

scubashack

Here are some pics!

Ironman

It may well have too much horizontal run. The basic rule is that you must have at least twice as much vertical height as you have horizontal run.

Also, once that pipe begins to go through the block wall, it cannot be run in single wall pipe. "B" Vent is required.

STEVEusaPA

I know for oil the chimney connector cannot exceed 10 feet, and the total equivalent pipe length of the connector (factoring total equivalent lengths of elbows) can not exceed 75% of the height. Do you have anything depressurizing the house?

EBEBRATT-Ed

How long has this boiler been in service and did it work before?

Could be a plugged chimney

could be a dirty boiler

Venting is questionable

kcopp

Give us some more history. Where does that vent lead to? Someone needs to look at the venting tables in NFPA 54

HVACNUT

Looks like its been that way for a while.
I would call a good chimney company and have them inspect it. Is there a cap?
I would also run new smoke pipe to the chimney without increasing the pipe diameter out of the boiler.
What really concerns me is a purge station on the supply and the PRV on the return. Bet you can purge the hell out of that boiler.

Jersey2

If it is a venting problem wouldn't you smell burning gas near the boiler, as it stalls going up the chimney? Maybe the venting could use some work, but it's not the cause of the switch being tripped assuming that it was working at some point.

EBEBRATT-Ed

You cannot run a vent connector (which is the horizontal section heading to the chimney) any length you want.

No one can say weather it's right or wrong until the job is measured and the vent tables consulted as @kcopp said.

Steamhead

@scubashack , where are you located?

HVACNUT

I agree the venting is wrong. But it's been that way for years without a problem.
I've seen many long horizontal runs through crawl spaces, under slabs, etc.
He needs a chimney co. If not a liner, a clean out door outside.
My bet is theres a nest or dead critter jammed in there.
I think upgrading an oil fired clunker to a high efficiency oil boiler in that situation is a no no. It'll be Niagara Falls.

scubashack

Ok here is some history on my boiler, it was installed by a local contractor in CNY back in 2002 or around that time!! Have never had a problem with it shutting down or tripping the rollout switch before! NOTE: same exact boiler using same venting as pictured was what this current boiler replaced... I can see it venting up the chimney on the roof, the run of chimney is approx. Same length as the horizontal run....the last 2 months I have had to replace the fill valve, pressure relief valve, put in a spirovent and replace my indirect hot water tank that was 9 years old because it was sending pressure back to the boiler causing boiler pressure to hit 30psi!! NOW I have a boiler that shuts down either because it's getting to hot....I say this because if I leave dampener open to let heat exhaust all the time boiler stays running, if I leave on auto where it open/closes boiler shuts down!! Any comments appreciated....

scubashack

Ohh yeah boiler has been checked out, everything is clean!!

scubashack

I'm also noticing that when its calling for heat/ or hot water the boiler will ignite for about a second then go out, then reignite and stay lit till coming to temp!!

scubashack

More pics!

EBEBRATT-Ed

@scubashack
If the damper is the problem than have it fixed. If it gives you a problem on auto that is a clue.

could be a bad damper motor or an intermittent problem like a loose wire or a bad connector.

a 17 year old system is going to have an issue from time to time. Dosent mean it's automatically junk.

But most people don't drive 17 year old cars

scubashack

I'm just trying to narrow what could be causing the problem.....heating contractor trying to get me into a new system saying that the current boiler is vented wrong and it is to far from my chimney!!

JUGHNE

When was the free standing WH disconnected? (pilot keeping pipe warm)
And could that 3-4" short pipe be pushed too far into the 7".

scubashack

WH was disconnected in 2010 then I went to the indirect WH, service guy was out the other day when boiler tripped rollout switch! He actually lowered the verticle vent to give it more pitch hoping that would help, before that horizontal vent was level

HVACNUT

Seems like a bad end switch in the damper motor.
If manual open works, then leave it open. You'll lose a little efficiency. Or you can order a Fields Controls GVD-6.
Also make sure all the molex connector wires are fully inserted and tight.

Ironman

The venting is borderline at best, not up to spec at least. Utica atmospheric boilers are very touchy about flue gas spillage if not vented as spec'd in the manual. It could be that something has slightly changed and become the straw that broke the camel's back. The spillage switch could also have become weak over time and now trips more easily.

I've seen this on several Utica's that we service, including one we installed. The vent height was borderline and it worked fine for the first year. After that, the spill switch started tripping and we had to leave the vent damper manually open. You could feel the draft spillage when it first fired for about 90 seconds, then it would suddenly draft fine. It didn't do that in the first year. Gas pressure and firing rate were spot on.

You also need to replace that over-sized flue pipe with the proper size. Bigger is not better in flue venting; it's actually detrimental as it causes "cold stacking" which makes it more difficult to initiate a draft when the boiler first fires.

Was a PROPERLY sized liner installed in the chimney when the boiler was installed? It should have been since that's an 80%+ boiler and it should not vent directly into a masonry chimney.

Connecting a new high efficiency 80%+appliance to an old chimney is a common mistake made by many installers. They don't realize that the old, less efficient appliance produced much higher flue gas temps and kept the chimney hotter.

It could well be that 17 years of flue gas condensation has deteriorated your chimney if it's not lined - and I'm pretty sure it's not - and caused part of it to internally collapse. I've seen that before also.

EBEBRATT-Ed

Also they lowered the length of the connection between the boiler and the first 90 (the riser) to get more pitch.

While pitch is good reducing the riser height reduces the venting. If you put a 90 right on a furnace or boiler vent coming off the equipment it reduces the venting substantially.

You should always rise up from the equipment as much as possible

scubashack

The chimney is lined, everyone has been great with suggestions!! Much appreciated....I'm running the boiler with the damper switched back to auto to double check something's! So far it's been running a few hours no problems, guess I'll wait and see if it shuts down again....

Ironman

I'm not talking about a clay liner. I'm talking about an approved metal liner that's insulated anywhere the chimney is exposed to an unheated area.