Tigerloop issue....baffling

dav

Hello,
I have a buderus g115/28 with a riello burner. There are 2 330 gallon tanks, in parallel with 1/2 inch pipe and union connecting them into the bottom. From there, a filter, the a Webster osv 50. Into a 3/8 inch copper line ran up to ceiling and over to the burner. Another general filte, then a tigerloop ultra. Here is my issue, the vacuum gauge that is installed reads 8 inch hg. If I press the manual bypass on the osv, the vacuum reading goes down to about 2 hg , as expected without pushing the bypass. Here is what I have done, I removed pump bypass, made it a single pipe system, removed tigerloop ultra and ran, vacuum reads right at 2.7 inch hg . That is what webster claims is the correct vacuum reading for their os valve. If I remove osv and reinstall tigerloop, it run at 0 to very minimal vacuum, as expected. There are no air leaks, oil line has been pressure tested, and vacuum tested, filters have all been replaced. What appears to be happening is the tigerloop can not open the oil safety valve all the way. It is a new tigerloop. What baffles me is when the manual bypass on the osv is pushed vacuum gauge read right around what it should. Suggestions or ideas would be appreciated,
Thanks
Dave

dav

Also, the tanks and boiler are both located in the basement, total run of 3/8 inch copper is 30 feet.

STEVEusaPA

Your tanks being connected at the bottom is not parallel.
The Tiger Loop makes your system 'ED' piped (2-piped, shout out to @EBEBRATT-Ed ). With the bypass plug installed should give you a higher TGSC (total gear suction capacity). If you held the OSV open for 5 running minutes (get the air out), does it improve your situation?

Get rid of the osv. Once you go up it's useless. It's only 'protecting' your oil line from the end of the osv to the level of the heating oil in your tanks.
I'd also do from tank-firomatic, general, spin on, tiger loop (firomatic at the inlet of the tiger loop).
But because your tiger loop has a filter, then just tank-firomatic-general-tiger loop w/filter (at burner of course).
You don't need 2 generals in a row or in series. And you don't need two spin on's in a row.
Multiple high micron filters need to be piped in parallel, not series.

If everything is vacuum leak free, and tight, you wouldn't even need the Tiger Loop (and no OSV either way) after a proper power vacuum bleed.

dav

yes they are in paralel, they are plumbed at bottom with 1/2 union going to a tee to general filter, they are plumbed at top with 2 inch pipe and union. so when filling the oil will flow to other tank over the top of tank through 2 inch pipe. because fill will fill tank faster than 1/2 will move to other tank. now as far as the tigerloop goes, here is what i found. it appears to me a design flaw, tigerloop will not not pull enough oil to flood the lines because the burner only uses .9 gph and the tiger loop will not allow more oil to come in than what is being used. to overcome this i opened the bleed screw on the pump, jumper the riello to run without flame, and then while running hold in manual bypass on osv. the gauge now reads 5 inch vacuum. still not great but better. i am assuming there is still air in the line that is compounding the problem. as far as the osv goes, i like it because if i lose a pump seal, or get a leak in a fitting or lineit will not siphon 660 gallons of oil onto the floor or into my boiler. as far as the filters go, i use a general filter at the tank and another general before the tiger loop because i mix used restaurant cooking oil and it can get pretty nasty. so i like to triple filter.

dav

to me, it stinks to have to bleed a tiger loop to get air out of the lines, it is possible, i guess, that the tigerloop will eventually do this, but how long? 1 year, 2 years? the idea behind the tiger loop was to not have to ever bleed the oil lines, because it can get messy. this seems to me to be a draw back of the tiger loop, because i use the gauges to determine if filters need to be changed. this means that the gauges are useless.

STEVEusaPA

There is no flaw in the Tiger Loop design if properly installed. Not saying they never break or fail. If you look at the Tiger Loops instructions, it tells you to bleed into a bucket for 5 minutes. To tell you the truth, I've never done that. It should work as advertised.
Your tanks are plumbed in parallel for filling, but not parallel for distribution. If they were parallel for distribution, one tank would empty into the other, and the fuel line would come out of that second tank. I wouldn't get hung up on the nomenclature.
You shouldn't be mixing in used cooking oil unless you're burning in a waste oil heater. You're asking for far more trouble than what it's worth, which you are now experiencing.
As I mentioned earlier, with a 2 pipe setup, you are pulling in and circulating thru the loop the entire TGSC, probably around 20gph. .9 gph @ 100psi gets burned, the balance goes back to the loop.
Any tiger loop system I worked on, the pump strainer is always blackened, which tells me it's seeing that 20 gph thru the fuel unit.
The OSV at the tank will do nothing for you if a pump seal fails and you have a tiger loop.
Your triple filter situation is wrong. After the first filter clogs, you'll lose flame. Based on your set up, I wouldn't be surprised if your oil line is full of crap, especially from tank to first filter. Also as your vacuum goes up, the more likely you will damage the pump and pump seals.
Most of your problem is probably viscosity related and introducing the cooking oil is the main problem.

I just gave you pretty much all the facts to properly pipe your oil system. You can do whatever you want.

dav

I do not mean to challenge your expertise. The setup I have right now is 2 330 thanks (yes in parallel, series would be in one tank through the next then onto the burner), a firomatic at the tee on bottom, then general filter, then osv, then 30 feet of line, then general filter then tigerloop ultra. I agree with you that there may be viscosity issue compounding the problem. As far as any filtration goes anytime the first filter clogs, you will lose flame. As far as cooking oil goes, it really is not different than 20 percent bionic. I have not had issue doing cooking oil for years now. I have proved to myself that the tigerloop is not able to.pull enough oil th through the lines to flood them. The pump in a single pipe system with no tiger loop easily does it, the only explanation can be the tiger loop can not release air fast enough to bring pressure down to reasonable. The burner still runs but I do not like the build up of vacuum, until all air is released. But thank you for your advice, it was definitely not bad advice, and I appreciate your help.
Dave

STEVEusaPA

You're right, not series. I hope you meant bio and not 'bionic'--the fuel of choice for The Six Million Dollar Man!
I think you problem is your application. The burner, nozzle, fuel pump, all the related seals & gaskets, the Tiger Loop & the OSV are not rated/approved for a (true) 20% bio mix, or as a waste oil heater application. Probably a lot of moisture in those tanks too.
Can't imagine the cooking grease counts as true/approved bio.
If I had to do it your way, I'd separate the tanks. I'd think I'd filter the waste oil before I put it in one tank. Then pump that thru a filter(s) again into the other tank and mix with clean heating oil.
Then try to run off of that. I think your problem boils down to viscosity, and clogging components from the tank to the burner. Something is causing a restriction.

In an up and over and down oil system, what goes up has to come down. I assume when you put the tiger loop back on you inserted the bypass plug? If you did, the tiger loop will pull a higher vacuum like a 2 pipe fuel pump, and once bled the vacuum should drop and stay dropped.
Does the bowl in the Tiger Loop fill up all foamy and eventually settle out, or stays foamy? Foam can be air or foam can be extreme vacuum.
You can try a power vacuum bleed. Usually cures the problem. Or simply remove the tiger loop, remove the bypass plug, power bleed the system.

Keep in mind, in the event of a disaster, a pretty keen insurance investigator might decide that you get to assume all the liability for using these components in a way not recognized by the respective manufacturers.

EBEBRATT-Ed

Get rid of the "Band Aid" tiger loop & the osv. Make the system two pipe and run a return line. Put the bypass plug in the pump. Make sure all the oil lines are 100% tight. Submerge the return line to the bottom of the tank.

Your burner will then run

dav

Yea bypass is in. There are no restrictions in line. Pressing the manual bypass on osv sets vacuum to 2.7 inches. That is all restrictions in osv, firomatic, lines and 3 filters. Run the system with no tiger loop and bleed and the system runs at 2.7 inches vacuum. Burner runs fine as it is, even at 8 or 5 inches but I did want to get the vacuum down to within reason. I will keep an eye on it. I may try to run single pipe bleed lines and shut off valve last filter, then install tiger loop again. We shall see. I am still convinced that the tiger loop is not flooding the lines with oil with the osv valve in. Without osv and tiger loop installed system runs at 0 to less than 1 inch. I may trash the osv,. And no the tiger loop never fills with foam just some air and disposes that as it should

EBEBRATT-Ed

@dav oil doesn't foam at the low vacuum you have it usually good to about 12" of vac. I would suspect air if your getting foam at low vacuums

SuperTech

I'm in complete agreement with Steve on this one. I've never had a problem with a Tiger Loop ultra, I think it is a fantastic product. I'd ditch the osv, 2nd general filter and I would definitely not recommended the cooking oil.

SuperTech

Also, if you want to continue using the cooking oil I would recommend using a nozzle line heater like the ones used on waste oil burners. May help with getting better combustion, but I don't think it will do anything for the vacuum issue.

EdTheHeaterMan

For my garage I have a used mobil home furnace blowing into a home made cottage base to blow across the floor for the last 12 years. I take the waste oil from changing oil filters, pumping out old oil tanks making other repairs and the like, put in a 275 Gal fiberglass tank and let it sit there. Using a Scully snorkel gauge I draw off the surface of the oil into a 10" Ful-Flo oil filter with out a filter cartridge. From there it goes into a 4" Ful-Flo with a metal screen cartridge. (I can't find them anymore so I clean this one) From there the oil goes into a tigerloop ultra. Firing a .50 gph nozzle... Each season I do the tune up and the 4" Ful-Flo screen on the second filter has next to nothing on it. Some water in the 10" used as a separator, but not much. The cindered filter on the nozzle looks like any other burner I maintain. slightly blackened but mostly clean.
SOOO.... I think getting rid of all the filters in series and loosing he OSV will resolve your issue. From the tank have the first filter empty to collect heavy sediment, The second filter should have a metal screen, (but I can't find a supplier for them anymore so you may need to make one) then pipe to the Tigerloop ultra installed near the burner. That is all the filter you really need!