My underground oil tank fittings: anything like this in the States?

belham

Well, guys, things get even more interesting here. I went out in my yard, beside the house, where the 3000l underground tank 2ft square (aluminum grate sealed-covered) manhole is, and spent more time laying on my belly & looking in there at the fittings on the top of the tank. Turns out I have an early version (1998-2001) of one of these (below). All this time I thought (or assumed) I had straight copper going down into my tank for both "suction" and "return" lines.

Since I have the early 1998-2001 version of this Afriso Miniflex, more than likely I bet I have only the one thick NBR "suction" line hanging down in my tank, and the smaller measuring line is not present. I also think the "return" line probably just dumps in at the top of the overall Afriso fitting, running down the outside of the suction hose. Kind of ingenious, these Germans. Solves all cavitation questions right there.

All the fittings in this manhole area are those German compression things I've previously spoken (and provided pics) of in other threads. Wow, the inner manhole area is clean as a whistle, no gasoil lying anywhere---even from the 15 years of fillups, with the fillup port right there. My gasoil guy/company has to drag that heavy fillup hose from his truck some 50 yards from the road. Wonder how he is keeping this inner manhole area so clean? Overall, this Afriso German stuff is interesting indeed.. .....but the "red" manual tank shutoff/on handle-valve? Lol, sprinting outside to shut down the flow, are they kidding me?? Cripes, what happens if we aren't home. Answer? Burn down the home. Oh, wait, can't burn down because there's no wood used to build homes---it is all brick, stone, concrete and tiles. God I love this country...think our homes here would be great nuclear shelters, haha (actually, no joke). Anyway, here's that Afriso Miniflex mentioned above: (any thoughts on it?):









Can't tell, whether like the later version (which is the pic above) if I have a check-valve built into my early version or not. Either way, its a darn good thing I never decided to use my Hausfield compressor to blow out both the 'suction" and 'return' lines back into the tank (starting from inside the utility room where the oil burner sits & blowing them back into the tank). I was actually thinking about it, given the (-0.5 bar) vacuum readings I am currently seeing while the burner runs. You know, like maybe starting at low pressure and building up to 60-70psi tops. Would have been quite the dumb thing to do.

Looking at the top tank settings (in this outdoor manhole area) is the craziest setup I have ever seen. Can't stop staring at that red shut-off handle (the red handle in the pic above). They don't spec firomatic valves here, so what do they think, so if something major happened---and I am not dead from it---how in heck did they think I am going to sprint out there and "manually" shut the tank flow down? Classic German over-thinking/engineering.


P.S. The third connection opening on the above Afriso Miniflex is for if you want to install a pneumatic gauge, even run it into your home if you want. My manhole area has a manual Afriso float-type gauge, and it quit working long ago. I stick it, using a marked 2 meter dowel, and I trust this way more than reading any gauge (in home and/or out there).

Ignatz

I'm retired now but was a Pa. DEP underground tank inspector. I also did Tank Tightness Testing, line testing, corrosion testing, ect. The on-off valve would be nice for a tank tester to flip one valve to isolate the lines and the level gauge.
Saw some weird stuff, but nothing like this. Over here many homes need a TTT when they get sold. Or change insurance companies.

Grallert

Ya good thing you didn't blow those line! Blowing out lines is considered a no no by many if not most techs here in the northeast any way. That tank fitting looks a lot like the fitting that come with the Roth or other similar imported tanks tanks here in the states. One thing I've run into with those flexible rubber subsection lines is collapse of the line. or a crack at the point where it connects to the brass fitting its self. Never really figured out why the rubber would collapse though. Might be worth removing that tank fitting and inspecting for issues.

belham

@ignatz, I bet you've got some wild stories from the PA heartland concerning tank conditions. I have zero idea of the age of this tank in the ground, previous homeowner didn't supply, and no one mentioned it to me. They only showed me the fuel lines and burner setup, which was all documented and installed in 2000 (I bought the home in 2005). I was too stupid to ask about the tank. Plus my German-French stank at the time (awe, who am I kidding, it still stinks). Dam# When I lay new copper fuel and return lines this spring/summer, sure hope I don't find years later I should have had the tank removed & gotten a new one. How can one test an in-ground tank without subjecting it to harm??

@Grallert hmmm, you've got me thinking. I wonder if that (the suction hose collapsing and/or partially collapsing) is why I am seeing that definitely not-so-good -0.5 bar (-7.3psi) vacuum reading during burner runs (everything else has been tested/replaced, save for the fuel lines, which I can't touch without a lot of digging plus ripping up the concrete utility room floor)? I've never seen gunk or residue in my lines, filters or anything, for 15 years now---- though I do stay on top of that stuff, plus cleaning the flue, chimney, and scrubbing the inside of the boiler yearly (which I am not sure why I do, as there's barely anything in there).

Let's see here: if I remove the Afriso Miniflex currently on there, that means I have to un-screw and disconnect both the "suction" and "return" line coming in there. Those are the German compression fittings. Crap, they left me absolutely no (zero) room to cut a 1/4" off both lines so I could re-seal them back up with new compression fittings. So how do I I get at the rubber hose if I can't get the Afriso Miniflex out?

Hey, think I could pull that b#sterd NBR hose up through the fuel fill port on the tank, and get a partially look at it there?? Use a steel snake line to gently bring it towards the fuel fill hole? Or is moving it after all this time going to cause damage to it, maybe even damage that is not currently there? I mean, it's NBR---doesn't NBR love to remain submersed in gasoil?? It should still be flexible and stuff....or, wait, you said you've seen rips/tears/cracks at the "top" near the fitting. Well, nuts, that is where it would have been "dry" all this time and prone to fail.

Not sure what to do now...haha

Ignatz

I'd ask your oil supplier or someone else to see what kind of tank you have. Not many home heating oil tanks over here with a manhole access. That doesn't mean its a special protected tank, but it could be a double-wall tank, or a tank with corrosion protection. Might be worth having someone look at it.
Also, over here, Tank Tightness Testing is a certified activity. Even though heating oil tanks in Pa. are not DEP regulated, a tester follows a protocol to their testing equipment. Generally I would pull 1 to 2 psi of negative pressure for a test.
I also would test the tank a much lower pressure to make sure it tested ok, before I pulled it down to the official test pressures.

Ignatz

BTW, a heating oil tank in Pa. can be regulated, but an example would be a gas station selling heating oil that left the premises. If its consumed on site, and doesn't leave the property...its not regulated.

STEVEusaPA

@belham I think its time you buddy up with a heating professional in your area. Buy him a bier or 5. They would be better to tell you about what is going in your area. You have things no one here in the states are familiar with (special hoses, fittings etc.). For all I know, that's what is code, that's what is standard in your area. If you try to 'Americanize' everything, you may make it worse.
Floating suction lines enjoyed a little spot light here for a while, but it seems like the old tried and true ways are still the best.

belham

Steve,

Everyone here is mostly DIYers, myself included----much like I tried to explain to you before for various reasons. Since I am an engineer by training, I tend to do everything myself. Recently just re-built a BMW 528i engine, which if you know anything about modern BMW engines, is no small feat. Home heating is no different. I thought that is what these forums were about, no? Several here (even today) have posted good stuff---like gellart and the hose thing. You did too in the beginning and it is much appreciated. But since you're out of your comfort zone here, you don't have to reply and advise something--like considering buddying up---- which I (or no one here) will ever do. This isn't the States. It's Germany/French/Belgian lands, where the villages are populated by people just like me. Everyone I know here is either an engineer, skilled trade technician or a mechanic of sort (hydraulic, trains, etc).

Oh, wanted to tell you that I talked to Danfoss people, told them what the burner is reading vacuum-wise during a cycle run (-0.5 bar). They told me directly that they test all their fuel pumps (for any type of failure) for equivalent of 2 year full cycle runs at near -0.9 bar. In other words, they said it won't be the pump that fails on my system if something goes wrong. Was even told if it does, to contact them again & they'd send a new free one out with same-day delivery. We both know trusting company techs (spoke to an engineer guy, not marketing) can be problematic, but maybe this might allow me to back off on the "worry" dial a bit & make it till summer where I can lay all new pipe all around.

And, also, learn about and put in new top-of-the-tank stuff like I am learning about in this thread. This Afriso stuff and NBR hoses in the tank, with manual and auto stop fittings on top of the tank, is truly something else

belham

@ignatz, thanks for the info on ways to test a tank. They regulate, actually over-regulate the crap out of everything here in Europe. Makes one realize how we in the USA (between State & Federal agencies) are still somewhat ok, not totally, but somewhat.

I don't think my tank is double-walled, but I am wondering if they installed it in its own cement, and lined pit. That seems to be popular around here. But given the age of my house, and I've been here since 2005, I have my doubts. I'll know more when I can get at the ground around it---when it thaws a bit.

Good news is I have several workers around the tank right now, been working their butts off the past 2-3 months. Translation: moles. The darn things are impervious to getting rid of them, and jeeezus do they move copious amounts of dirt in my yard (my yard is about 3/4 hectare, or 1 acre). At the rate they're going, I really think---if they wanted to---they could have the darn tank dug up in 2 months tops...or at least a deep trench all the way around it.

I need Marlin Perkins from Wild Kingdom here to talk to them

STEVEusaPA

belham said:

... But since you're out of your comfort zone here, you don't have to reply and advise something--like considering buddying up---- which I (or no one here) will ever do...

I'm not out of my comfort zone at all. I gave you the proper advice to solve your problem. You're suction line is either clogged or has partially collapsed-that's the reason for your high vacuum.
Myself and others explained the downside of a 2 pipe system, you seem to want to ignore that. Don't know what else to tell you.
"Buddying up" simply meant there must be someone around there that knows about oil systems.
All those skilled people where you live and no one likes to help each other?

EBEBRATT-Ed

Over here it is best too run the return line close to the bottom of the tank. This "seals" the oil line system so no air can migrate back through the return line to the burner pump.

belham

Hi Ed,

Wish i had this option, but with an underground tank, I am SOL when it comes to doing that. I've gotta live with the return line pouring in at the top, right over & down the NBR suction tube hanging 1 1/2 meter down into the tank.

Out of curiousity, yesterday I tapped on the Afriso suction-return lines brass fitting at the top of the tank, while the burner was running, and a little bit of black stuff headed promptly sailed straight up through the suction-line and into the see-thru glass filter (hanging on the side of the boiler, filtering fuel coming in...the Danfoss fuel pump also has another fuel filter inside it). And lo and behold, the vacuum gauge dropped straight from -0.5 to -0.45 to -0.40. Since they (Afriso) put a check valve in that brass fitting (on the suction line at the top of the tank), I am wondering if that check valve is "gunked" up after all these years, and that is what is causing my horrible vacuum and/or air problems. I've no clue how to clear up a check valve built into a tanktop device like this---other than removing it & replacing it, which means (again), screwing with oil lines & their over decades old German compression fittings (the fittings look in great shape, but still, I am loathe to screw with them until I actually lay all new pipe & new fittings. Is there a trick to ungunk a possibly clogged up check valve on a suction-line like this, that's on top of the tank sharing also the return line coming in?