Vaillant Boiler burning smell

TomVaillant

All,



First time posting here so please go easy.  I have a Vaillant F70-W-45 oil burner for our hot water radiators, probably about 15 years old.  Been living here for about 5 years and there haven't been any problems with it until this summer.  I took out a radiator during remodeling and when I went to refill it a bunch of water leaked out the pressure reducing valve the day after I refilled it.  Tried this one more time before leaving it until this fall-- I can't say it ran more than 10-15 minutes total when I was bleeding the radiators.  Well I just replaced the PRV and a check valve on the water supply and it is now happily at ~14 PSI.



Unfortunately when I fired up the boiler there was a burning smell... maybe a mixture of diesel and rubber?  the Flue seemed fine so I removed the jackets and saw a vertical crack about 3 inches long on the left side between two of the plates were it seemed like there should have been some fiberglass rope.  Hoping to get this boiler to last one more season I JB Welded the crack shut which seemed to have worked, but there is still a burning smell when the boiler is firing.  It seems like it is coming out near the hot water gasket at the top of the boiler.



I'm wondering has the boiler cracked and exposed a rubber jacket?  Anyone know where I might look to see what is the issue?  There haven't been any water leaks yet.



Thanks!

Alan Welch

May be time for service.

Boilers that have been off for several months generally need to have flue passages cleaned before running.  Renovation/ dust  can affect burner operation. No water in boiler can also cause a smell , I would call for service and leave it shut off.

Steamhead

Vaillants

are an earlier European type of boiler, and they don't like improper burner setup. If the burner is not properly set up, the boiler will plug with soot, then the flue gases will try to escape any way they can. This is probably what you smell. The boiler will likely need cleaning and the missing section seal replaced. Also the refractory in the firing zone may be damaged or missing, and need replacing. Lynn Products makes a refractory kit for this boiler.



Where are you located? Have you tried the Find A Contractor page of this site?

TomVaillant

target wall?

Thanks for your help.  I cleaned out both the bottom and top of the boiler and indeed there was a lot of soot... after your suggestion I also looked closer and found two of the channels that go up from the bottom chamber to the top on the sides completely block with soot.

I checked Lynn Manufacturing and noticed they talk about a target wall.  Is that something I should have in this boiler?  The picture shows the current view in from the front.

I'm actually in the northern Virginia area.  I see a guy in Lorton so I may give him a ring.  I've had this serviced before but all they do is change the nozzle, filter, vacuum and split.

Steamhead

The circular piece in the rear

is the target wall in this boiler. So yours is still there. Also there should be baffles in the vertical passages, but I've never seen a Vaillant that still had them.....

RobG

Boiler Service

The service company in Lorton Virginia is Foley Mechanical. Do not hesitate to call them. You're lucky they service your area.

Rob