Oil furnace losing fuel prime
We have a ThermoPride oil furnace, ~8 years old, that gets a bubble in the fuel line if it sits for more than a few hours. The burner comes on and if the fuel is not available it trips a breaker on the pump.
Is there anything that will cause this other than leaky tubing? We just bought the place and as part of the deal the previous owner was req’d to replace the underground tank with an aboveground. New tubing of course was required for this job.
Thanks for your advice.
Replies
Try clicking on "The Wall" over at http://www.heatinghelp.com/
I'd check for a leak first.
But if the tubing is clogged or kinked (basically obstructed in some way), the pump can stall or cavitate.
End up with similar result.
"Let's get crack-a-lackin" --- Adam Carolla
Try checking the following;
Is the fuel pump piped in without a bypass? If so, any leaks in the supply line will suck in air whenever the pump pulls a vacuum as it draws oil from the supply. Then it will cavitate and lose prime.Use the bypass feature on the pump if it has one, or replace it with a pump that can be piped with a two-pipe system.
How long is the supply run to the furnace and does the pump have to pull against any head pressure. On long runs, even a two stage pump will have problems pulling cold oil, and even a tiny vacuum leak will cause air to be sucked into the fuel line. If the pump can't handle it, then you may need to add a booster pump close to the supply tank with an adjustable bypass feature that will provide just a small amount of positive pressure in the line to the furnace.
Just a couple of things I learned way back when I was servicing oil fired furnaces and heating boilers.