Cleaning an oil furnace?

I usually notice the same smell the first few times I run the furnace for the season. It seems to go away after awhile. I'm not sure why. The burner and air-flow should be completely seperated.

According to the service guy who last looked at it, a persistent smell is indication the burner is starting to go.

if Its running on an old nozzle, it may be getting coked up from residues left from years of burning oil. Im no expert, but it doesnt take much heat to coke them up. If its not atomizing properly, you can get a tiny bit of unburnt fuel in the firebox, and you can get the smell from that. A new nozzle is about $10 and you can change it with a 19mm wrench (on most models that is). Apart from that, I am not too sure.

I use a commercial atomizer burner for hobby metal casting/forge work, so thats where I get what burner knowledge I have, so consider the source. Again, I am no expert, and have no training, this is just shade tree mechanics at its finest.

In reply to Datsun1500:

I've been doing it on my parents house for the past few years. I dedicated a crappy shop vac with a Gore Cleanstream filter to do the job. I went to Home Depot and built a vacuum hose to reach into the heat exchanger. I got some reinforced rubber hose about 1" diameter and sorta stiff about 4-5ft long. I hooked it up to a vacuum nozzle adapter with some shrinktube to make the snake assembly. You clean the heat exchanger by going in through the exhaust. Remove the ducting and you should get access to a big drum, thats the heat exchanger. Your goal here is to clean out all the soot from the walls with the vacuum. I use a long PVC stick to knock loose all the soot from the walls. Insert the hose and try to snake around to the back of the unit.

Word of advice, absolutely do not clean through the view or combustion chamber. If you see a white chamber, do not get tempted to go clean it or near it. You can easily destroy the chamber walls which will then result in burning through the heat exchanger and a chamber relining job. Ask me how I know.

The first time I did it, it was absolutely gross. My parents haven't had a tune up or cleaning in years. Crazy amounts of ash. I would go and get yourself a real respirator too when doing it. It is a very filthy job. Clean out the ducting by banging it on the floor and vacuuming out the debris. The whole system works on "draft" to sorta suck the fumes out. Clean the chimney too, that can contribute to your smell problem. Near the chimney is your draft regulator. Make sure that section is reinstalled level or the way it came out. If you smell persists, then you may need to tune the draft more or you could have a heat exchanger crack or leakage point somewhere.

While cleaning and tuning up, I found all the stuff the tune up guys did hack jobs on. Now for the standard disclaimer, I am not a pro so do this at your own risk and if your house burns down, blame yourself.

I've been doing my own for years. Over a decade in fact. Got the manuals, but not the cool tools.

You can clean the nozzle yourself easily. You can replace it easily (dirt cheap too, like $5 or so). It all slips out of the furnace very easily, usually just by disconnecting the high pressure fuel line.

That said, this year it's all gone to heck in a handbasket, and I think I'm going to buy a service contract. I've had oil pooling on the basement floor, many fireballs, plenty of no-starts, etc. Not sure why, the unit is very unhappy now.

In reply to foxtrapper:

Sounds like an issue with the burner. Does the unit recieve new electrodes, cleaning of stack control, cleaning of the screens in the pump, oil filter clean, all electrical connections good, high pressure line bled?

One of the coolest things i've done when I started to do this work myself is add gauges and add quick disconnects for everything so I can rip the burner unit and the system fans out.

I have a gauge after the oil filter and a gauge right after the burner pump. I can see the nozzle pressure is at spec when I open the service panel.

I thought about doing it myself until last year, when I was dispatched to a house fire that turned out to be a near total loss. He had just serviced his own furnace and, since he had done it many times before, he thought he knew what he was doing.

I'm not sure how much of the damage was covered by his insurance, but I have since vowed to only have mine done by an insured pro.

i just did mine.

step one: unhook oil furnace from chimney

step two: install Vogelzang woodburning furnace and duct into plenum above furnace

step three: never buy oil again