Oilburners , Figure 5 , or the Fuel Systems Handbook ( FSH ). In this case we ’ re using ( FSH ) so the numbers will reflect that text .
In the New England states , most of the places where we must deal with outside tanks are primarily commercial applications , seasonal homes and mobile homes . In the mobile home application , the solution to cold oil problems has always been to “ switch them to kerosene .” Let ’ s set up a little scenario from 1993 and reintroduce you to a couple of my fictitious characters , Bubba and Bruce of B & B Burner Service . Bruce has been in the business for 22 years and has seen some problems over the years . He is a good diagnostician and a first-class burner tech . He is the owner of his own service firm . Bubba is another story . He is Bruce ’ s nephew , has been in the business five years and is coming along , but he sometimes is in a rush to fix things . Sometimes he comes up with ideas that boggle the mind , what some might call a “ rocket scientist ”, a “ space cadet ”, a “ moon shot ”; well you know what I mean .
We find our heroes on a service call where they have been unable to get the burner running . Outside the temperature is + 5 º F and dropping . The customer is getting upset because he has his sick 90-year-old mother upstairs in bed and the kids all have the flu . ( Ever wonder if these people follow you from job to job or has this just become the standard excuse ?)
Bubba has been on the job for a couple of hours and Bruce has decided to drop in on him to see whether he has a problem or has merely gone comatose .
“ So Bubba , what ’ s the problem , are you gonna make a career of this job or what ?” asks Bruce .
“ I got cold oil Uncle Brucie , I mean industrial grade , high viscosity , move over Jell-O , heavy duty Vaseline , won ’ t come out of the tank . Cold oil !” answers Bubba . “ You mean you can ’ t get it to flow at all ?” “ No , not at all , but I ’ ve been thinking , what about an oil nozzle preheater , Brucie ?” “ First , you got to get it out of the tank , Bubba !” “ What about a tank heater ?” “ Good , what an idea ! Where do you think , you are , the Arctic
Circle ? What ’ s the firing rate , and where ’ s the tank ,” Bruce continues .
“ The firing rate is 0.65 ( gph ) and the tank is outside against the garage , and before you ask it ’ s a one-pipe gravity job with ¾ inch line and all the valves are open . The filter is on the wall here in the utility room and there are no compression fittings , Teflon or any other outlaw materials in the line ,” continues Bubba . “ Also , the one thing that I can get to happen is that if I fill the filter bowl with fueloil , I can get the burner to run .”
“ Hmmmmm ,” answers Bruce . “ You know that gives me an idea ! Have you got any 2-inch fittings in your truck ?” “ Sure ,” answers Bubba , “ but what do you have in mind ?” “ Well , let me draw you a little picture . Let ’ s say that you could heat up the oil and only draw from the tank what you needed to burn . What you need here is a flow rate of about 0.01 gallons per minute . Pretty small , right ?” questions Bruce . “ Boy , it sure is ,” answers Bubba . “ So , look at this drawing , Figure 6-3 . Let ’ s say that we put the pump on two-pipe operation , and heat the oil using the heat of the room and friction . We take a piece of pipe and create a sump or reservoir for heat transfer , we get the pump to produce its maximum vacuum and get it to pull all it can against
Figure 6-3 that cold oil in the tank and see what happens . Well , let ’ s get what we need together ,” continues Bruce . “ Let ’ s see , we ’ ll need a piece of 2-inch pipe , a duplex tank fitting , a tee , a coupling , a reducer , some copper tubing , some flare fittings and a flaring tool .”
“ How long does that piece of pipe have to be anyway ,” questions Bubba . “ About 3 feet of 3-inch pipe will hold about a gallon of oil , and about 3 feet of 2-inch pipe will hold about a half-gallon of oil ,” answers Bruce , “ but , I would rather use the 2-inch because of the fittings . Here Bubba , look around and see if you can find some 2-inch pipe clamps too .”
In Figure 6-4 is the preheater that Bruce and Bubba put together . As you can see , it is a piece of 2-inch pipe with a ⅜ inch ips eccentric reducer to feed the pump supply port on one end and on the other end they have put a 2-inch tee with a drain and a duplex tank fitting which allows for both the supply line from the tank and the return from the pump to get to the reservoir .
“ Why are you putting a level on that pipe Uncle Brucie ?” questions Bubba . “ And you ’ ve got it pitched towards the tank supply line .”
“ Well , I ’ m concerned about water . You see , we will bring in oil which is about 70 degrees colder and heat it . With this pump , we will be moving quite a bit of oil around the circuit . The pump will only draw from the tank what goes out the nozzle , but with the pump on two-pipe we ’ ll have quite a bit of oil going around the loop ,” answers Bruce . “ And , with the drain , if we do condense the oil , we will be able to drain it . Let ’ s fill up the loop and see what happens .”
“ About how much oil do the different pumps move anyway ?” asks Bubba .
“ Well Bubba ,” answers Bruce , “ if memory serves , the Danfoss pumps move about 15 gph , Suntec pumps about 17 gph ( now 15
Figure 6-4 www . fueloilnews . com | FUEL OIL NEWS | JUNE 2019 47