Welcome from Dwaynes Garage

[Dwaynesgarage]

Hi Y'all, I am Dwayne and I have recently installed a Clean Energy 140 furnace. Its a used unit with 1000 hours and this is my first kick at the can with waste oil heat. I don't really know what to expect from it and I have a couple of questions for the more experienced.
I have what looks to be a healthy flame, fires right up with little to no smoke while running. But..
I have unburnt fuel in the combustion chamber after running and smoke up the stack after shutting down.
Is this normal?
I have the settings for air flow and pressure set to factory and 1 psi of oil pressure.
Any help would be greatly appreciated.

[Russ]

Welcome Dwatbesgarage!

Is this happening after running the heater for a longer period of time?  Like at least a half hour?  It takes a while to warm up the inside of the heater and get everything up to temp so all of the oil burns.  Be sure everything is getting good and hot.  I would think as long as everything is good and hot it shouldnt smoke after shutting down.

[ShopSpecialties]

Hi Y'all, I am Dwayne and I have recently installed a Clean Energy 140 furnace. Its a used unit with 1000 hours and this is my first kick at the can with waste oil heat. I don't really know what to expect from it and I have a couple of questions for the more experienced.
I have what looks to be a healthy flame, fires right up with little to no smoke while running. But..
I have unburnt fuel in the combustion chamber after running and smoke up the stack after shutting down.
Is this normal?
I have the settings for air flow and pressure set to factory and 1 psi of oil pressure.
Any help would be greatly appreciated.

You should have no smoke coming out the stack. So lets start with some basic stuff first.
What is your elevation ?
Firebox clean ?
Clean nozzle ?
12-14 psi for air ?
Clean combustion air blower ?
Flame should be 1/2-3/4 to the target.
Flame should have a bright yellow body with orange tips.

[Dwaynesgarage]

Thanks guys for the quick responses. I have the furnace now working better.
After a thorough cleaning of the burner, nozzle and combustion chamber there was little difference so I thought that the only thing it could be was fuel.
My waste oil is 95% full synthetic. I read that some furnaces don't like that so I lowered the flash point with a little #2 fuel oil (10% or so) and things seem to be ok.
What are your thoughts?

[ShopSpecialties]

Synthetics burn fine but the issue is getting them to ignite. If it fires right up then it is fine. Was all the ash a fine white-tan powder ?