We ran out of oil for our furnace last week, which I have since discovered is not a good thing. I knew we were getting low, but with oil at $3.85 a gallon, I was trying to nurse it along to the end of the heating season. Obviously we didn’t make it. When we first ran out, I thought we could get by without heat and fill up the tank later when prices are lower. But after a couple nights with the house temperature dropping into the fifties, I quickly changed my mind.
I called some local oil companies to get a delivery of 20-25 gallons just to get us to the end of the season. No go. Every company had a 100-gallon minimum for delivery, and no one was budging. However, a couple of the companies told me that diesel is actually the same fuel as home heating oil. So I filled up two five gallon containers of diesel at the local gas station and poured them into the tank through the outside fill line. The furnace still wouldn’t start.
I did some poking around online and found out why it is not good to let your tank run dry. First of all, you suck all the sludge from the bottom of your oil tank into your oil lines, filters, strainer and nozzle. And secondly, you usually lose your prime. Well, I didn’t know what to do about the first problem, and I am not much of a fix-it-man, but I did some more searching online for how to prime the oil burner pump. Here are the basic DIY (Do It Yourself) instructions:
First, make sure that your thermostat is turned on. Then, 1) turn off your furnace, 2) open the bleeder valve on the fuel pump, 3) turn the furnace back on, 4) allow air, oil and sludge to escape from the bleeder valve until you get a solid flow of oil (be sure to catch the escaping oil in some kind of container), 5) close the bleeder valve, 6) repeat the whole procedure if the furnace still does not start.
I found a couple articles explaining this procedure in detail, but the best one by far was this one at WikiHow: How to Restart a Furnace After Running out of Oil. The other articles instructed me to hold a container under the valve when you opened it to catch the oil that would come spurting out. But this WikiHow article gave me the best tip of all — run a short section of 1/4″ nylon tubing from the bleeder valve to the container. I picked up a two-foot section of nylon tubing at the hardware store for 80 cents and went home to bleed the fuel line and prime the pump. The tubing worked perfectly and prevented a huge mess of oil everywhere.
The instructions online told me this was about a five minute procedure. I multiply estimated times for projects by a factor of six, so I guessed it would take me about half an hour to get this done. And it did! But the furnace is running again, and we now have heat to warm up the house in the morning. I would refer you to the WikHow article referenced above for complete instructions, but here are some helpful hints I learned along the way:
- Don’t let your tank run dry.
- You can substitute diesel for home heating oil in a pinch. (Five gallons of fuel will give you about five hours of running use.)
- The bleeder valve is located on the side of the fuel pump, pointing down diagonally, usually at the 4 or 8 o’clock position. It most likely takes a 3/8 inch wrench.
- Run 1/4″ clear nylon tubing (1/4″ inside measurement; 3/8″ outside measurement) from the bleeder valve to the catch container to prevent a mess. Clear tubing will allow you to see when you get a good flow of oil going from the pump.
- You may have to repeat the procedure several times to get the prime going. I didn’t get any oil flowing until the sixth try.
- If your reset button is in lockout mode (mine was), you will have to press and hold it for about 40 seconds in order to reset it.
- You can take the oil you capture in the container and pour it back into your tank.
If you came to this article looking for information, I hope that helps. I am not very good at this stuff, so I am guessing if I could get my oil pump primed and running again, so can you!