Beckett AFG boiler - rumbles and vibrates

Ann

A Beckett boiler (model # CLW-4-P) and burner, AFG series, model #1GPHN22LE were installed in May 2003. Everytime the boiler comes on, it rumbles and vibrates throughout the entire 2-story structure. There is no pre-purge and was recently cleaned.

What could be the problem?

Also, the second floor return vent emites a loud, grinding, metallic sound everytime the heat or A/C comes on. This has occured from the date of installation. The HVAC people told me that they pulled out plastic packing that was left in the vent and also discovered that the motor fan was operating in the wrong direction.

Any idea about what could be the cause for this continuing problem? During the summer months, it was also impossible to keep the second floor cool. The HVAC people told us that was to be expected in the hotter months (their explanation sounds suspicious). The system is First Co., model # 36MBXBHH hydro coil heat and air conditioner (3 ton).

Any ideas out there?

Thanks!!

ThermalJake

Anne,
I found some more info. I'll bring it in to Larry tomorrow.
John

ThermalJake

To everyone else:
Anne is looking for info on the causes of a rumbling and vibrating boiler. I think it is related to too much fuel or too little air.
I think it is a W-M with a direct vent and an AFG.
The purge question was asked by the contractor who did the routine cleaning recently. He thought that the vibration could be fixed by adding a pre-purge.

Ask whatever questions you have. She could use some expert opinions.

Thanx

Jake

Jim Davis

Rumbling boiler

The problem sounds more like air in the oil lines and nozzle assembly. If in fact this is a direct vent then it would be post-purge (8-10 minutes) that would be necessary but that is not the only cause of the rumbling. Low pump pressure, bad nozzle or selection, electrode settings, weak transformer, two line system are a few more things that cause this problem. Fuel-air mixture problems would quickly fill the house with smells and smoke in most cases.
Post-purge is necessary to keep all the oil in the drawer assembly from dripping out after shutdown from excessive heat. This would definitely cause poor ignition and noise.