Boiler Bangs loud on startup.

Butch_4

I have a Weil McClain oil boiler WTGO Series 3 and it has a Weil McClain burner QB-180 on it.  It's about 7-8 years old.  For about the last 2 years it sometimes bangs so loud and sometimes it is very quiet.  Mostly loud though.  We have a raised ranch with no basement so we hear everything.  It has been maintained yearly and has a service contract on it.  It was cleaned last Friday.  It was nice and quiet on Friday but yesterday and today right back to the banging.  For about the last 2 years hwe were told that it is because it's starting from a cold boiler.  During the summer we only have it on in the morning for showers, dishes, etc.  I would agree with him on the cold boiler but it does it when it calls for water to heat and the boiler is warm.  It is running a lot in the morning so it is warm.  Friday when I complained to the service tech he called in and they now say it is because the oil line comes up in the garage and inside the ceiling and comes down where the boiler is.  It's been like that for years.  They say the pump is working harder.  I don't believe them at all.  I have to clean off the top of the boiler where the stovepipe goes as it sometimes blows soot out.  Anyone got ideas?  Thank You in advance.

Alan (California Radiant) Forbes

Banging Boiler

It sounds like a delayed firing.  



My experience is mostly with natural gas, but I went out to a job recently that had the same problem.  It turned out that a spider had built a web that covered the orifice of the first burner, the one that the spark ignition is mounted on.  There was no gas coming out of the burner and ignition only occurred when enough gas from the other burners reached the spark which sometimes took in excess of 10 seconds, enough gas to cause a small explosion.

lchmb

pre-purge

It may help to have a primary installed with pre-purge. Not being there it is hard to run diagnostic's on the unit. Have you had the same tech for each call? May help to ask for someone else or ask for a field supervisor..just some thoughts..

icesailor

QB Banging:

There is an unfortunate history to that burner. Weil-lain put a lot of energy into that burner and there was some problem that has never been explained. They stopped making it after insisting that it be installed on their WGO Gold boilers. There are no new parts for it. Only scavenged old parts. They are very specific on nozzle brands, spray angle and shape. The one that work the best for me is not available unless I want to purchase 192 of that exact nozzle.

If the wrong nozzle is in there, and it isn't set up like the manual suggests, it will do bad things. You sound like this has been an ongoing problem. My solution to this problem that has been 100% effective is to get the Carlin OEM burner for the boiler it goes to.  

Replace the burner. Someone may want it for parts.

icesailor

Pre-Purge:

I've done quite a few of these. 402000, 502000 or 602000. If they have the wrong nozzle and aren't set to the specs in the install manual, thet will misfire. 602000 pre-purge and post-purge made no difference.

They were not a stellar burner.

lchmb

..

 

lchmb

personally

I've had excellent luck with all but one of these units (replaced) I have a spec sheet I carry in my truck and dont vary from it. I do know they no longer make parts for it, but I still liked it.. As far as this gentlemans case, your correct, right nozzle and setup is a must, hence why it may help to have someone else (supervisor) check the unit...And yes, it is probably a good thought to consider replacing the burner in the near future. If something fails that cannot be replaced it could be a cold night...

billtwocase

parts can be had

It was a good burner when set up right, like any other. The electrodes most likely need replacing. and can be had thru Sids. #414 should be the part number for those. The burner worked quite well on Golds, others will feel differently about them, but I have never had a problem with them, and have many in the field. You need a serviceman who knows the burner, among other things, and set it up with combustion equipment.

lchmb

correct me if I'm wrong

Bill I've been told the drawer assembly is the big item. You may be able to find used, but no one I've spoken to can find new...

icesailor

QB Parts:

That's why with every one I replace, I find someone who wants the old one for parts. I've never thrown one away for scrap. Someone may need a part.

lchmb

I have 4

I presently have 4 complete burners myself. I just dont like to install used parts or have someone rely on the thought I may or may not have one...Sooner or later, they will need a burner..and it's proven it wont get any cheaper...

STEVEusaPA

air........

The only way to confirm an oil line problem (could be a slight air leak) would be with a vaccuum gauge on the pump.  It could be losing it's prime.

Tell your 'tech' guy, to show you with a combustion analyzer, that the unit is tuned properly--draft CO2, O2, excess air, the ask him to put the pressure and vaccuum gauges on the pump to show you how it's 'working harder' because of the old lines.  Have him pull out an OEM spec book to confirm the right nozzle is in there (size & brand), and the nozzle assembly is at the right setting, and there's no crud on the end cone.  Basically, go over the burner and do it right.

Annual cleaning is the best time to take a burner, and make it worse if not done completely, and correctly.