Fuel Oil Connection

Ted_Ryan

Have a smoothly operating two pipe Trane system that was JStar'd in 2012 and 2013. The burner is supplied by a one pipe feed from an underground oil tank. JStar installed a fuel oil de-aerator in front of the burner and this has worked well. I am transitioning my fuel supply to twinned Roth tanks in the basement. The new plumbing is being done to go back to two pipe feed from the tank and eliminate the de-aerator. Is this a knucklehead move and should I request one pipe feed and maintain the de-aerator? I know this is not specifically steam related, however, I am hoping to get some honest advice like I used to get from JStar. Thanks.

deadmansghost

I would go to the two line system.

Steamhead

You don't need to hook the new tanks up with two pipes. A single pipe and the de-aerator is fine. The advantage of this method is that the filter doesn't handle nearly as much oil flow, and there is less chance of a leak from a return line (which runs under pressure rather than vacuum).

Depending on how far the tanks are from the boiler, you may not even need the de-aerator when running single-pipe. A single pipe running up from the tanks and back down to the burner will work as a siphon, and if the pipe run isn't too long, will overcome the friction in the pipe without any help at all.

On a longer run, however, you may need the extra suction capability that the de-aerator will provide.

I don't have my chart handy that shows the critical pipe lengths, but I'll either dig it up later or one of the other experts will chime in.

Ted_Ryan

Steamhead and deadmansghost, thank you for the input and varying views. The pipe lengths are about 13 feet (a foot up, six feet across to the burner and six feet down).

Steamhead

What is the firing rate of the burner?

Ted_Ryan

Steamhead, my notes from JStar indicate a .85 70A nozzle. Is that what you are looking for?

Robert O'Brien

What Steamhead says!

Steamhead

Ted_Ryan said:

Steamhead, my notes from JStar indicate a .85 70A nozzle. Is that what you are looking for?

Almost. What pump pressure did he use?

RJMCTAFO

I always abandon return lines when I can. One less chance of an issue. Have had 0 issues with using Tigerloops in this situation. It's there and it doesn't cost anything to use it. Why change?

STEVEusaPA

Did I miss something...what happened to JStar?

Steamhead

STEVEusaPA said:

Did I miss something...what happened to JStar?

His company was bought out, and the buyer hired him and his whole staff. Haven't heard from him for a while, I hope he's doing well.

Ted_Ryan

Steamhead, Joe S. did not leave me that information. The only other flow related item I could see on the burner was that the input was set at approximately .625 gph. I would ask JStar, but he just disappeared. Thanks.

Steamhead

What make and model is the boiler?

Ted_Ryan

The boiler is a Smith 8s3.

Steamhead

Nice boiler. That boiler can be fired at one of two rates. But even at the higher rate, at 13 lineal feet a single line of 3/8" OD copper line will work fine, even without the de-aerator. The rise from the tank is counter-balanced by the fall to the burner, which forms a siphon.

I would have them install an oil safety valve before the filter, which will cut off the flow if a leak develops at the filter or the burner. Also a Firomatic valve which will cut off the flow if the ambient temperature goes too high, as from a fire.

If we find a two-pipe system on an indoor tank, we change it to single-line, using a de-aerator if needed. This cuts down on service problems.

Ted_Ryan

Steamhead, I think I understand everything you are saying, however, one more question. What is the logic of pairing indoor tanks with a single fuel line? Is it the issue you mentioned about the oil filter handling less oil flow? Also, thank you again. I looked back at past postings and you were equally helpful several years ago when I first started taking ownership of how my trane vapor system was being managed. Ted Ryan.

Steamhead

Glad to help.

Not only do you have less oil flowing through the filter, but you don't have a return line that runs under pressure and can leak.

Two-line systems came into use with underground tanks decades ago, because they could develop more suction and could prime themselves if the tank ran dry. But there's no need for two lines when the tanks are in the basement with the boiler. One line works fine, and if you want to be self-priming, use the de-aerator (a.k.a. TigerLoop).

New England SteamWorks

I second Steamhead. Single stage, single line is all that is needed. Can't fathom why anyone would go with a a two pipe system in your situation. It is all a matter of vacuum. More than 6" of vacuum requires a two pipe.

Every 1' of lift equals 1" of vacuum, every 10' of horizontal equals 1" of vacuum, so based on your measurements you're less than 2"of vacuum. I personally think the Tigerloop would be overkill, and I am not a big van of OSVs in normal conditions.

What worries me is how they came to the conclusion that two pipe was needed? Because of two tanks?! I'd be a little nervous/cautious...

Ask them their reasoning.

Ted_Ryan

Good advice. I will see what they say. I already have the tiger loop, so it seems logical to leave it in place and go with the one pipe. They spent a lot of time staring at the directions for the Roth tanks, so I am not sure how thoughtful they were on the set up between the tank and the burner.

RJMCTAFO

Make sure they are certified by Roth. The warranty does not apply unless they are a certified installer.

Ted_Ryan

Yes, thank you. I checked that box early in the process. That is what was strange about all the time spent pondering the installation instructions. Probably just something they don't do every day. I checked the basics of the install....dead level front to back and side to side and no evidence of leaks...the tanks have been full since November, just waiting to consume the oil in my underground tank left over from last season. Next check will be when they are flowing to the boiler and get refilled again. Cheers.