Utica Combi Boiler (MAC-150)-Error 133- Causing big bang noise after few trial of combustion

hcpatel78

Hello All,

I have Utica combi Boiler ( Model # MAC-150) installed few years ago. Lately it is throwing 133 error . I just cleaned the Flame sensor but still it is throwing 133 error after few times trying to get ignite when hot water calls.

Heating is off by the way.

Also when it ignites after few trials it makes a loud ignition bang noise that is scary .

Please advise what needs to be done to resolve 133.

Condensate line checked— Not clogged

Gas line—-3/4" sized…

Thank you,

109A_5

Was everything on the list for that error verified ? If the spark is poor OR not where it needs to be it won't work correctly.

https://uticaboilers.com/wp-content/uploads/2022/02/MAC-Boiler-Manual-REV-A-WEB.pdf

HVACNUT

Yes, its scary. Which is why there are qualified people in the trade to make sure your extremities stay attached to the rest of you. A few years is 3,4? Has it ever been serviced? Has it ever met a combustion analyzer?

SuperTech

I would definitely check the vent pipe and air intake. Tuning it with a digital combustion analyzer is crucial. These things are not good to go out of the box. Professional installation and maintenance are needed for reliable operation.

hcpatel78

hello all . Thank you for all suggestions. It turned out that Igniter was not working properly. Replaced Igniter and Flame Sensor solve the problem.

hcpatel78

"

Was everything on the list for that error verified ? If the spark is poor OR not where it needs to be it won't work correctly.

"

Yes you are absolutely right.