OT - Oil Burner Nozzles, Filtration Requirements

[dalmatiangirl61]

This does not sound like a normal furnace.

Define normal, LOL. It is a military surplus H82 furnace in a box, 120v power + fuel = 120,000 btu of instant heat. Dual shaft motor runs squirrel cage blower on one shaft, other shaft drives a Suntec pump, solenoid controls fuel flow to Delavan nozzle. Main difference I see from conventional furnaces is instead of a shutter to control air/fuel mixture, you adjust fuel pressure, according to manual at 6000ft elevation it should run at 80psi. Pictured is the unit in my living space, the unit in shop has ductwork on output side and is not easy to photograph as duct obscures main panel.

I found a NOS fuel oil filter locally that looks like the one linked to in post #17, and I think it will fit without too much modification. Next time I have to pull burner I will instal the filter. Burner is behind the access plate on right side/heated air outlet in pic, since the one in shop has ducting, it requires removing ducting to get to burner nozzle.

Some years back I did run the unit in shop on 50/50 mix of waste oil and diesel, it ran and burned great, but did result in a clogged nozzle. I'm thinking the main problem here is the fuel needs better filtration.

 

[dgfoster]

Just FYI I run my nominally .75GPH nozzle at 11.4 L/hr diesel with the fuel pressurized to 12PSI but restricted by a needle valve. Atomizing air is at 45PSI. These are not according to the spec sheet. But that nozzle has been bullet-proof.

Denis

 

[Superbowl]

Waste oil is a lot thicker than diesel. First, are you aggressively agitating to ensure they are fully mixed so the thicker oil is diluted? Then the question comes up... even if well mixed, will the oil clump later if it sits?

 

[dalmatiangirl61]

Waste oil is a lot thicker than diesel. First, are you aggressively agitating to ensure they are fully mixed so the thicker oil is diluted? Then the question comes up... even if well mixed, will the oil clump later if it sits?

It has been many years since I tried the waste oil mixture, I did agitate it well, no idea what it did after pouring it into fuel tank.

 

[dalmatiangirl61]

Just FYI I run my nominally .75GPH nozzle at 11.4 L/hr diesel with the fuel pressurized to 12PSI but restricted by a needle valve. Atomizing air is at 45PSI. These are not according to the spec sheet. But that nozzle has been bullet-proof.

Denis

That sounds like a different kind of setup, this unit has no atomizing air.
Edit: If you mean combustion air, a percentage (value unknown) of the air from the squirrel cage fan is fed in behind the burner via a 2"-3" dia tube, there is no provision for controlling amount of combustion air.

 

[dgfoster]

That sounds like a different kind of setup, this unit has no atomizing air.
Edit: If you mean combustion air, a percentage (value unknown) of the air from the squirrel cage fan is fed in behind the burner via a 2"-3" dia tube, there is no provision for controlling amount of combustion air.

Yes, the nozzle I am using is a siphon nozzle—-SNA in Delevan’s terminology.

Siphon Nozzle

Works well for my purposes and often used in commercial boilers I believe.

Denis