Oil Pipe Run

[Jez]

Trying to get the heating on for my new build.

I've got an underground oil tank that's set 2m into the ground. The tank is fitted with an Atkinson tank top.

The pipe run comes out of the tank top in 10mm qual pipe and runs fairly flat for 34 meters. It then turns into a setvice pit and over the next 500mm connects to a fire value, filter and tiger loop then drops 4m into the basement to the boiler.

After days of trying we can't get the oil to flow. Atkison's say that it shoukdn't be a problem, but it obviously is. The Oftec installer that I've used says I need to buy an oil lifter. I'd rather not as its electrical and one more thing to break down.

The boiler runs if we rig up a tempory tank before it drops into the basement and using a wet vac we can feel suction down the pipe.

Suggestions please as its getting cold!!

Thanks in advance,
Jez.

 

[EPH]

Can you not get any oil at all to the Tiger Loop?

 

[SimonG]

You have air being pulled innat joints. Redo them all.
Check that you have the flow and return correct on the tiger loop. Try another tiger loop, it could be buggered.

 

[SimonG]

Whats the qual pipe laid in?

 

[EPH]

Try putting the feed pipe to the Tigerloop into a suitable container with oil in, at least you can verify everything after that is working ok.

 

[Jez]

Blimey fast responses, thanks.

qual pipe is run in 50mm ducting and will be back filled in the future.

we put the feed for the tiger loop into a 25litre oil container and it ran fine till the oil ran out.

can't get oil through to the tiger loop.

cheers, Jez.

 

[lame plumber]

did you use flared joints or olive connections with inserts, flared are by far the best option.

Another thought is that you should be using 6mm supply pipe as you have a suction head of 2m to get oil out of the tank over 34m run, which requires a 6mm pipe diameter, I know it then drops another 2m to the basement but I am assuming the fall isnt an issue. So 10mm pipe wont work as theres too much space to get the correct suction effect get your technician too look at his books, section 2.2.6 of tech book 3.

I hope your tank is secured down well in its hole with strapping, if it isnt, youll be amazed how well it floats down the line

 

[Jez]

Pipework was done by the oftec plumber. Normal compressions, no inserts.

Their solution is to buy an oil lifter, but to my mind is the power of a wet vac can't get the oil through I don't see how an oil lifter will.

None of the joints are weeping, but I guess that doesn't mean they are air tight. What the best way t ensure they are air tight?

 

[lame plumber]

reread my other edit re pipe sizing, more likely to be the problem, re checking the pipeline for leaks, it should have been pressure tested as part of the commissioning process!!!!!

 

[tamz]

At the risk of sounding obvious............Bypass screw?

 

[Jez]

Plumber assures me he fitted the bypass screw and we did have the bolier running from a temp tank.

 

[MarkOil]

tank valve is turned off.
tank top ones work a bit different, try blowing down the pip, if you cant, valve is off.
Bu with it going up 2m and along 34m you will need to following the priming instructions in the boiler manual to get it to the tigerloop, or manually suck it to there first, but bare in mind it may nearly be there and if you let air in the end the oil will very quickly return to the tank.
Turn tank on and use vacuum pump to prime, then job done.
But check the bypass screw is in and the tigerloop is actually filling up when you attach 25l container to feed, if it does collect oil in the tigerloop then it isnt creating a vacuum to pull the oil.

 

[Jez]

Been looking around and long lengths of 6mm pipe is hard to find.

anybody know where I can get any?

 

[tamz]

Your 10mm qual will be fine. Follow Marks advice above.

 

[lame plumber]

Your 10mm qual will be fine. Follow Marks advice above.

out of interest Tamz, why do oftec say otherwise? I know the world never bothers but have had issues and resolved them by following pipe sizing guide in the past

 

[tamz]

What works in practice is often different to the theory.
Qual pipe has an id of 6.8mm. A baw hair bigger than 8mm copper.

 

[lame plumber]

never used qual pipe , only ever used copper, dont trust plastic stuff

 

[tamz]

Neither do i :lol:

 

[Jez]

Mark,

just to check, we put the feed pipe to the tiger loop in the 25l container. Boiler then ran for a couple of hours, so presume that proves the tiger loop works?

We are using a wet vac to pull the oil though, but when we stop to connect the pipes back up the oil runs back. Only ever seem to pull oil to the end of the qual pipe, sucking after the fire value and filter doesn't see to work.

don't suppose you fancy a trip to Dunmow?

Jez.

 

[MarkOil]

It will have oil in the clear bowl when it is working correctly.
Is the firevalve open? button pushed in or pulled out depending on which one you have,
When you pull it through and have oil coming through with the vac, shut the tank valve, turn vac off, then connect all pipes tight, open tank valve and fire boiler.

 

[lame plumber]

got a leak then havent you, could slip a non return on tank outlet but only real option is to cure your leak.

 

[Chalked]

Definitely an air leak.or kinked!

 

[MarkOil]

Chelmsford Plumbing and Heating Ltd Aren't a million miles away, on the Which trusted traders website.

 

[lame plumber]

Pipework was done by the oftec plumber. Normal compressions, NO INSERTS!!!!!!!!!!!!!!!!!!!!.

Their solution is to buy an oil lifter, but to my mind is the power of a wet vac can't get the oil through I don't see how an oil lifter will.

None of the joints are weeping, but I guess that doesn't mean they are air tight. What the best way t ensure they are air tight?

just reread this, try using inserts, you might get a decent seal, better still do it properly with flared fittings

 

[Chalked]

Qual pex fittings require inserts.