Expert: James Ball - 11/19/2008

Question
Hi, James...

I'm having some issues with a gas boiler I installed myself as a replacement for my old oil boiler. Two weeks after installation, I started getting some pretty bad flame rollout. The heat exchanger was plugged and I couldn't get it clean, so I called in a pro. He cleaned it, but rollout remained unless the pressure in the gas regulator was turned down to 1 1/2 (from its recommended 5).

The guy I called was perplexed. I have since come to believe that, while a nice guy, I think he's strong on the "plumbing" part of his plumbing & heating business.

The draft hood was sitting way too low. I took it off and replaced it with a draft control in the 7" line. The rollout ceased, even when turning the pressure back up. I turned the pressure back down to where he had it, as he was supposed to come back this past Monday and set it at 5 with his meter.

He didn't show, and now I see that there is rollout again. This time, it is just coming from one corner. I pulled off the exhaust and can see that the unit is sooting up again, thus the rollout.

Now, the pressure had been set down on the regulator and when he was here, he said he was changing another setting (I forgot what he said) but he inferred that would also lead to sooting, but he was trying it to attempt to get the rollout stopped.

Does this sound like I have a serious problem or more likely that the unit just sooted up again because of the setting changes he made? I called his cell phone and told him he needed to get here to reclean this thing and set everything to where it should be, now that there is a dual-action draft control in the line.

I should add that, when the system was installed, a 3" liner was put on the boiler, as I have a masonry chimney. It's a Burnham 144,000 btu boiler.

This is driving me nuts. The boiler burns a nice flame, but this sooting thing is aggravating. Can you give me any tips on what else to look for?

Thanks very much!

Cheers,
-Rusty-

Answer
Hello Rusty, lets start with some basics a 144 BTU natural draft boiler, in a 20' tall chimney, 2' lateral from the chimney should be into a 6" round liner (holding 188,000 BTU's) this could have a lot to do with the roll out and sooting up (you say 3" liner was installed?), next do you have any make up air for the boiler? or are you in a dead air room? If so then you will need a "fan in a can" your plumber will know what that is. next did you contact the manufacturer of the boiler?
this unit "rolling out" can be very dangers get it right ASAP
keep me posted
James