The reason Riellos seem to have a problem priming is that they don't pull at 100% until they come out of prepurge. Then there are only 5 seconds of running time until the safety times out.

They make a special tool to get around this and there is also a way to fool the burner and keep it running until it has pulled the oil to the pump. It is just as easy to use the push pull pump. Gets the oil ther fast and clears the line. I have the same boiler/burner combo as you and am very happy with his system.

 

Ask your contractor about installing a Tiger loop.

 

1) Is a 1-pipe system pulling from the top of the oil tank an incorrect installation? Note that the oil is pulled up out of the tank, but then drops down to floor level at the boiler. The basement is now finished so it would be disastrous to consider changing anything about the piping run.

2) Can, and should, the second pipe be connected to the Riello pump for a 2-pipe system? The second pipe is already laying there, and so I imagine this could be done with 1-2 hours labor. Is this the proper way to have installed this system, and could you tell me if, in your opinion, this will definitely eliminate any issues with the priming of the oil pump?

I would appreciate it if anyone might provide answers to these two question. I am trying to determine whether this suction issue is easily remedied or not. Thanks!

 

For a reillo its not correct.

Can, but better off with a tiger loop.

 

Thank you. Last question then: Will Tiger Loop solve issues specifically with suction? While I see it helps remove air and gases from the oil, I don't see where helping maintain suction is one of the benefits. Have you personally seen the tigerloop help with this specific problem?

Thanks.

 

Yep. not on that particular burner. But on others.

 

The problem you will continue to have is no one figured out or fixed why the pump lost its prime. Where is the oil filter? I'd bet when the service was done, the tech didn't replace the filter canister properly, and didn't bleed the pump properly. Did anyone put a vacuum gauge on the fuel pump?
You mentioned the oil line is now concealed, which is not good for ever finding a leak.
If I were at your home, I would do one of 2 things.
1. I would replace the line into the tank with a floating suction line. Coming out if the tank I would put a ball valve, then the filter. Along with the device earl mentioned, you are now able to power purge the fuel pump. Also, before I replace the filter cartridge and break the fuel line, I bleed the pump into a container, and save the clean oil to put back into the new filter cartridge--makes bleeding easier.
2. As beenthere stated, install a Tigerloop ultra and you'll probably never have a problem again.

 

a tiger loop with make it keep prime but it won't fix the problem. if it ran fine for 4 years until the tech had troubles then he must have done something wrong. something is leaking somewhere. you could switch to a 2 line system but probably not necessary. plus you need a kit to convert the burner anyway. at least I think you need it. I can't remember if it can be done without it or not. but anyway, it must be able to be fixed. I would ask for a tech who is familiar with these burners. many techs are still scared of these burners because they are not experienced with them. I have only ever installed one tigerloop and it was in my old shop for a hanging heater and I got sick of pulling the ladder out to bleed it and was to cheap to change the pump. they definitely can be handy but I try not to use them. I had a service manager years ago who put them in everywhere, and they aren't cheap.

 

Any burner that sucks out the top of the tank with one line will have problems eventually. Get a Tiger Loop and your problems will go away.

 

why do you say this? I don't doubt you have a reason but I have seen some really, really old one liners with no delivery issues.

 

Thank you all; this has been hugely helpful. Please continue to opine if anyone has anything additional to add. Thanks again, Craig

PS 48 hours since the tech restored my heat... but I am not confident that I won't experience another loss of pump prime, as that occurred about 45 days after my annual servicing in November. It is possible, if the original tech caused the delayed issue by something he didn't do (tighening filters, valves, purging or whatever...), then perhaps that different tech that restored service on Sunday may have remedied the problem. It's hard to know for sure.. I'm starting to wonder if I should get educated on this system and just manage it myself!

 

what and why will it ruin a pump if it has a solenoid? if everything is done right and clean, air should not be in the line.

 

If you put a check valve in and the pump has a solenoid when the burner stops the oil in the line could warm to the point it increases pressure and ruin the seals. Thats what I was told years ago when I was putting in check valves.

 

I guess this could happen, but the burner would have to be running bad and something plugged but I still think it's unlikely. I have 2 boilers out there with check valves,
I'm not a big fan of them because of noise and added moving parts. but they also have a place. I have only had noise with one. other than that no problems. one is in a 2 line system. I am not even sure why it's there but am a bit suspicious of it because the riello pump is starting to whine.

 

if the oil heats after the solenoid it will just pressure the gun line and drizzle out the nozzle.

if the oil heats between the solenoid and check valve that section of the line and pump. i would think that it would take a massive amount of pressure to blow the seal on a pump. after all, you're pushing 150 psi normally.

if the oil heats before the check valve, the check opens and the pressure equalizes up to the solenoid.

 

Can't say for the Reillo oil pumps. But Suntec and Webster oil pump seals blow out if the pressure on them exceeds 10 PSIG.

 

This is from Suntec

Do not use check valves in gravity feed (tank above pump) single-pipe systems, or in a system supplied by a boost or transfer pump. Thermal expansion can cause serious problems

http://www.suntecpumps.com/CheckValves.htm

 

yes, this I knew, you left that part out in your post. lol you are adding pressure and heat. I can't picture a gravity situation where a check valve would be required but, it must have happened if they need to put it in the warnings. lol

 

does riello use suntec pumps now?

 

not that I know of. why, have you heard that?

 

No they don't but they don't have much suction to begin with so a check valve isn't going to make things better. My statement was more of a general type thing towards overhead lines. Take it for what its worth. Just trying to help.

 

it all comes down to good installation practices. bad flares and poor connections will always cause problems. excessive overhead height may also cause air to be stripped out of the fuel oil and it could 'act' like an air leak.

also, if there is no flexible fuel line to the burner the yearly opening of the unit/bending of a 'hard' line may cause a break of seal.

that's pretty much what that document you posted said anyway - check valves are attempts to hide bad piping.

 

Well, a month and a half went by, and guess what? Yes, once again, Riello pump lost its prime.. I pressed the reset a couple of times, and no firing.
Recall that this system worked fine for 4 years, and after the flawed servicing in November, this is the second time I am having oil company come to restart the boiler. Very odd that each time, system operated for 6 weeks before failing / losing prime. Not only odd, but a ***** to diagnose/resolve. Please reread my initial post in January for more detail. Any suggestions? Should I connect up the existing return line (currently unused) to the pump? Should I install a Tiger Loop? Is there a way to "de-gunkify" my oil tank (which is only 10 years old)? Please help!

 

I always use the two pipe system. No problems. Run both lines to near the inside bottom of the tank. Then no splashing from the return line.

 

While I am working through this issue.. does anyone know if there exists a low-cost alarm or other way to be notified when the burner/boiler fails to start? Right now there is no timely way of knowing.. we don't usually find out we have a failure until the house temp gets cold, or someone winds up with a cold shower!...

 

Your electrician can help you out. He can hook up a wire that turns on a light or sounds a buzzer when the burner kicks out. You might have your service man fix your system to use the return line. Most oil pumps can be fixed so this will work.

 

Thanks Lentz.. I may have both of these items done as you suggest.

How would the light or alarm be wired up? ie what changes electronically when the burner kicks out?

 

A good electrician can figure this out for you. By hooking up a switch that closes when the burner kicks out.

 

Back again. So, here's an update.. It appears that the reason the oil pump is losing prime every month and a half or so, is that the oil filter is plugging up more quickly. The expected cause is sludge in the tank. How it got there I will never know.. could have gotten a crappy delivery at some point. Or could just be buildup over the years. The tank is only 12 years old, as I had our inground tank removed in 2002.
Would love to get your thoughts. My current plan is to use a fuel tank additive to slowly thin out the sludge. I am not sure if this is a practical solution or not.. have any of you had experience with sludge, and is there an additive you swear by? How long should this reasonably take? By the way, I plan to use Hot 4 in 1.
As I expect this may take some time, and I will still have continued plugging of oil filter for a while, I was wondering if it might be a smart idea to learn how to change the filter myself. Is this something recommended to DIY, if one is a reasonably intelligent person (I repair my own home appliances). I just think it might make sense to be able and prepared to do this myself instead of calling the oil company whenever I have a no-heat situation. Eventually they are either not going to cover me, or require me to have them replace the tank, which they told me is on the order of $2,000

Would really appreciate your expert advice and recommendations.. thanks!

(Oh - forgot to mention... the reason I expect sludge is that I am now noticing the suction gage at the oil filter slowly creeping up... I never looked at it in the past because I never had these loss-of-prime situations. Does it make sense that a plugged up filter will cause the oil pump to lose prime all together eventually?)

 

Just have the sludge pumped out. The oil company might be able to do this for you. Or you can raise the oil line a little so it will not pick up the sludge.
A little thinging will solved this problem.

 

If it were me, and you truly think this is your problem, I would do a few things things:
1. Replace the supply line with a floating suction line, out of the top of the tank. Here's a link to what one looks like:
http://www.spx.com/en/tigerholm/pd-mp-floating-suction-line/
After the floating line at the top of the tank I would put in the filter, like the standard General A25with the vacuum gauge.
2. At the burner, I would get a tiger loop (or ultra if you want double filtration with a spin on--couldn't hurt), remove the return line to the tank, and put a flex line return from the oil burner to the tiger loop.
3. Remove the copper return line to the tank.
4. Go to the bottom of the tank and pipe in a ball valve with a threaded plug (threaded plug you leave in just incase someone opens the valve.
5. Start treating the tank at every delivery. After a delivery (the next day), bleed some oil out of the bottom of the tank and check for sludge and water, into a small container (old milk jug). Sludge, will look like black goop, water will make the red/black oil look milky. You can even make a short whip out of the left over copper and a fitting to attach to the ball valve.
6. Make sure you tank is full at the start of summer.
7. Treat until the water is no longer present. The sludge really wont be completely removed unless you have your tank cleaned. And by cleaned I mean opened up and sucked dry.
8. Next year, and every year when you get your annual service done, check the filter cartridge (which is why I recommend the General) for sludge and water.
9. When things are looking good, treat tank in the fall with the first delivery.