Air in fuel supply - Tiger looop??

[quattro64]

Hi All
Hope someone with more experience than me can help.
I have problem with an installation the boiler is higher than the tank by about 1.5m and I am getting an almost constant stream of air bubbles in the tiger loop.
I have checked all fittings and they seem good.
Do tiger loops ever fail and would they exhibit these symptoms ?
Regards

 

[Dotty]

What size is your pipe from the tank to tigerloop?

 

[quattro64]

Hi
Thanks for reply.
pipe is 10mm
Boiler has run fine for last 3 years?
Cheers

 

[Best]

You might still have a leak in suction side - check / replace oil hoses or oil filter can leak at seal.
Or tiger loop is knackered

 

[lame plumber]

or return fm pump leaking as well, not sure how a tiger loop can go wrong, arent any moving parts in there are there?

 

[Best]

or return fm pump leaking as well, not sure how a tiger loop can go wrong, arent any moving parts in there are there?

Yea, the tiger loops can & do go wrong. There's a check valve in them & also a sort of float. I don't know what actually happens them, but have seen 2 leaking & also at least one that suddenly wouldn't let the burner work. Certainly if the check valve fails & the oil in tank is at a lower level, then oil won't hold in T.loop. Tiger Loops are recommended by the manufacturer to be replaced every 12 years. I carry a spare tigerloop just incase.
I meant to say earlier that the return hose is a likely cause of sucking in air to a Tigerloop but not showing a leak at hose.

 

[quattro64]

Many thanks for replies I will probably try a new tiger loop and check connections again.
As a side issue, as they are now mixing a percentage of biofuel with the oil could this cause problems with the tiger loop?
Thanks

 

[Best]

Many thanks for replies I will probably try a new tiger loop and check connections again.
As a side issue, as they are now mixing a percentage of biofuel with the oil could this cause problems with the tiger loop?
Thanks

No, don't change the tigerloop yet. Wise to bring a new tigerloop but first try changing the oil hoses & a very likely cause is the return hose from the oil pump to the tigerloop. If it has a pin hole in it then air will suck into T.loop but the other hose would often cause a leak or boiler to fail. Change both hoses if they are not brand new.

 

[quattro64]

Thanks Best, will be going there tomorrow.
Cheers

 

[MarkOil]

school boy error, but have you put the bypass screw in or taken the cirlip out the fuel pump?
be interesting to see what sorts it, tiger loops can be faulty, and yes you can have dodgy hoses, but if your installing a new boiler, I'd like to think that you have 2 new hoses :S

 

[Bunker]

I find that the 2 pipes from the tiger loop are often badly bodged into place with loads of compression joints, no inserts and then all rammed into the boiler - wall mounted system boilers being the worst. Only last week I begged the custard to let me rip it all out and re-pipe it. I even took the expansion vessel out and piped a new 18l one in. Install was in a garage - why the pheck people put system boilers in when there is tons of space around them for the components. Ah, I guess thats the difference between an installer who services and an installer who doesnt..... (rant over)

 

[quattro64]

Many thanks to all whom took the time to post.
I changed the two flexi pipes on the boiler, they looked ok but were nearly 3 yrs old. Unfortunately didn't cure problem but prob worth doing anyway!
I took new Tiger Loop with me and after comparison the one fitted was different obviously an older model. Swapped it out and appears job done. Nothing visibly wrong with old one externally - when Ive got 10 mins I will take it apart just for curiosities sake!
Thanks again, great forum!

 

[Best]

Many thanks to all whom took the time to post.
I changed the two flexi pipes on the boiler, they looked ok but were nearly 3 yrs old. Unfortunately didn't cure problem but prob worth doing anyway!
I took new Tiger Loop with me and after comparison the one fitted was different obviously an older model. Swapped it out and appears job done. Nothing visibly wrong with old one externally - when Ive got 10 mins I will take it apart just for curiosities sake!
Thanks again, great forum!

Thanks for letting us know how you got on. You were right to replace the oil hoses as they could have been faulty or badly abused or fitted & at 3 years they need to be replaced anyhow.
I have seen Tigerloops fail & it does puzzle you at first. The older tigerloop had the connections for oil pump coming from the base, but the new Tigerloops have those connections from one side (which you choose which side that goes towards).
On point about Tigerloops is they are no longer permitted inside ANY building or boiler house & must be fitted to outside because they vent to atmosphere. This IMO makes everything a bit of a mess & over complicates it all, but you can use the more expensive BIO tigerloop inside with a 10mm vent pipe to outside.