I have a Weil McLean Gold Oil Burner (hot water heat) that was installed about 4 years ago. At that same time I had an addition put on our house so we now have 4 zones. Whenever the main zone kicks on, there is a loud rattling/vibration noise throughout the house (essentially where ever there are pipes/radiators for that zone) for about the first 30 seconds. If the burner is still on for a long enough period, the rattling will start up again. In the winter, if the pipes are cold, the rattling is even louder.
I don't know the first thing about how the burners work, but do know that there is a metal "box" at the front of the unit and a little light will turn on when it first starts up. When that light is off, there is no rattling. I think there may be a different light for each zone.
Again, this is only for one zone. No issues when the heat kicks on for the other zones. My oil guy can't seem to figure it out.

Thanks!

Have you bleed the zone with the problem?
What kind of zone valves/ brand?

Hi hvac1000,

I apoligize in advance for my ignorance as I know very little about oil burners. First, my initial description is wrong. Last time I tried to figure this problem out, the "metal box" at the front of the unit did have lights, but checking tonight, it must have been replaced.

This part is currently labeled "EZ Pro Carlin Combustion".
I also see 4 TACO Cartridge Circulators.

The tag on the burner shows that my oil company wrote "New Circ. - main zone" last year when trying to fix the issue. It did not help this problem.

I know I've seen them bleed my radiators in the past. Do you recommend I try this again? Have you seen this issue before?

Much appreciated!

Usually when a water system has a problem with noise it is with in the pipe system. The only thing in the pipe is supposed to be water. When air gets in the system it can cause many different noises. Many people ask how air can get into the system and usually it is from heating the fresh make up water. When that happens it releases air into the system.

((The tag on the burner shows that my oil company wrote "New Circ. - main zone" last year when trying to fix the issue. It did not help this problem))

Usually when a company says it will replace a part and the system will be OK there should be some kind of warranty with that issue. I hate a noise in a system.

I would agree with HVAC1000 that it really never hurts to breed your zones, but be careful not to introduce more air.

Just wondering, and this may or may not be pertinent, but has anyone bothered to check the PSIG reading on the expansion tank?
Improperly regulated system pressure can cause knocking too.
Is it possible that the new circ pump of yours is busily hammering away trying to circulate water while a failed zone valve remains in the closed position?
Normally an end-switch has to make contact once the valve is open before the zone pump will be allowed to energize, but who knows?

HVAC1000,
Would you normally replace a circ pump for knocking sounds? Unless there's grinding noises or lots of cavitation noises(quite separate from knocking noises), I wouldn't usually jump to the pump and impellor assembly. Thoughts?

First step in a knock sound is air removal.
Next step is to use a scope or if you do not have one use a screwdriver and listen to the pump. In very few cases have I found a pump to be defective causing a banging sound.

Knocking is usually caused by the expansion of water in the line. When there is no air the expansion has to go into the expansion tank unless full. If tank full isolate and drain then reopen to the system.

Just to clarify, it's not a knocking sound. It's a loud vibration/rattling when the heat first kicks on (for about 20-30 seconds) during whatever the first "process" is.

Thanks

First we need to separate the two. Is this a Water link noise or a oil burner noise. Sometimes a oil burner that needs a tuneup will sound like all hell is breaking loose for a short time when just starting. It is a sputter back to the burner that usually causes this.

You have had your new oil boiler for 4 years. Have you had it tuned up. This is supposed to happen every year. Just doing this will save you the $$$ on your oil bill.

I've had it serviced every year.
My uneducated guess is that it's an oil burner noise that resonates throughout all the pipes/radiators in the main zone.
The heat kicks on. I hear the blower initially start up first, then a fairly quiet buzzing noise (not quite sure what process is occurring during this). It is during this process that the vibration/rattling is consistent throughout most of the house. Once that process stops (again, it's about 20-30 seconds), everything is quite in the house. The burner is still doing it's thing, but that initial process is complete.
Sorry if I'm confusing the issue...

Buzz= Ignition Transformer Normal sound

Vibration and rattling = bad burner light off
Call for service on your oil burner.