Tank outside, cold affecting psi?

[BryanDowdy]

I am setting up a used waste oil shop heater I bought and have the oil tank outside. During the day the heater runs fine, but at night it trips the flame sensor because the pressure drops. I'm assuming this is due to the oil getting colder at night (around 0°F). Would going to a metered pump solve this issue or must the oil be kept warmer?

[Russ]

Is this a siphon system?  If so, I suppose the oil is thickening up and not flowing inside as quickly as it should when the temp drops and your heater isnt getting enough fuel.

I dont have any experience to say for sure, but I would sure think that putting a metering pump on would help keep the flow of oil consistent even with oil temp fluctuations.

[BryanDowdy]

The heater is Shenandoah 315,000 and the pump does siphon from the tank. Thank you for the feed back.

I've also thought of fabricating a smaller tank to put in the shop that would stay warm.

[doug]

http://www.centralohioheaters.com/DSCN9645.JPG

does your heater look like this? where is your pump located?

[BryanDowdy]

Yes, that's the heater I have. The pump is mounted outside on the tank. The suction line is roughly 8' long of 3/4" pipe. The pressure side is roughly 32' of 1/2" pipe.

[doug]

what regulates your pump? how do you know the oil volume/pressure at the burner. if you look down on the red tank the gray box is a metering pump. I believe it's needed to be used with your burner.

[ShopSpecialties]

You need a burn tank inside and the bigger the better to make life easy. The pump can pump the cold oil it just cannot pull it through the filters.

[BryanDowdy]

A regulator at the burner sets the pressure.

So if I move the tank inside, I should be able to use the pump I have?

[ShopSpecialties]

Yes and also keep your suction side short and simple.

[BryanDowdy]

What's the minimum temp I should keep the oil at? At night I let the shop get down to 38*-40*

Thank you for the help.

[ShopSpecialties]

Those temps should be fine.

I know these heaters very well and if you have any questions at all just ask away.

[BryanDowdy]

What is the normal operating fuel pressure for this burner? I was told 2-5 psi, but in order for mine to achieve the flame length of 1/4-1/3 down the chamber that is called for in the manual; I'm closer to 8-10 psi. Do you know what the temp range is that is normal for the heated air coming out of the blower? Thanks

[ShopSpecialties]

Oil pressure is going to vary depending on a few factors. Weight/temp of oil, inches of vacuum you are pulling at your Lenz filter, how clean the preheat block is, nozzle size. You should always adjust your flame by sight and then look at the gauge to see where it is. Also you should have zero smoke coming out the stack.

Air temp is determined by both the room air temp and size of flame but you should be able to maintain 150*. That firebox design is not very good for hot air temps.

[BryanDowdy]

Ok great, thank you.

Yeah, my box temp currently at 6 psi is only 100-105*. I'll get the tank moved inside and get the pressure re-adjusted.