Oil burner keeps getting air bound

P00nz

Just bought a house a few months ago and we're having issues with the oil burner. It keeps getting air bound and locking out, if I catch it quick I can bleed the air out but a few times I have not been able to and had to call a guy in to help troubleshoot. We know there's air coming in but can't pin point it, he's changed a few lines already since some were kinked pretty badly. Also changed the oil line from being bottom fed to top fed with a check valve at the tank

My system is as follows:

Tank in basement with oil burner the line runs out the top (originally the bottom, but this was changed recently) the line then runs over head maybe 5ft and then across about 10-15 ft and then down the wall through a filter then it T's off, short run to the oil burner and the longer run to water heater. 

My guy says we should run the line from the bottom the tank again but  of going run the line on the ground so there's constant gravity pressure priming the pump.

But my thinking is what if it's getting air bound when both units are on if the water heater is calling for oil and it's strong enough to suck from the oil burner instead of the main feed line couldnt that be creating the air pocket at the oil burner? If this is happening then changing the way the line runs won't matter right? my water heater doesn't lock out maybe it did once or twice but my oil burner happens a few times a week. 

I've researched a tiger loop and I would have to run 2 lines from the tank for each unit since a tiger loop is supposed to run on just one unit. 

I'm thinking about just running another line to separate the units I can add a tiger loop to the oil burner if the problem persists.

Sorry for the long post just tired of bleeding air every other day or so in a cold home. 

Big Ed_4

Why did you change from a bottom feed to a top feed ? A check valve will cause more of a problem then cure . If its sucking in air from air leaks , the added restriction of the check valve would only help suck in more air ... With over head lines , air leaks and trapped air will cause lock outs .

P00nz

What you said makes sense. I guess my oil burner guy missed that day in class? I believe the thinking behind adding the check valve was to prevent product from syphoning back into the tank. 

Jon_blaney

I have a similar setup, a furnace and a hot water heater with the same problem. In your case, I think the overhead run is part of the problem. Also remember that the hydraulics change as the fuel level drops. I think separate line for each unit which run along the floor will work. I went the Tigerloop solution. I installed one like you propose but had to add the second to get it trouble free. My system is totally reliable now. Tigerloops are not just for air leak issues. They help to overcome hydraulic issues.

Big Ed_4

Yes , I was first taught to use check valves until it was explained to me not to use them .. They are only good for direction of flow under pressure . Some old burners needed them , and some old wall oil lift systems used foot valves in the tank to keep the single iron pipe oil line primed ... The inline check valve hung around like a bad habit ....