Powermax 155x Flue Problem

[Phil_M]

Hello all!
I've spent quite a while searching through the forum to find an answer to my problem with my boiler, but had no joy. Wonder if anyone could help me out?

I moved into my new flat back in November. All was well with the boiler apart from the programmer didn't work, which after reading through various posts on here, wasn't a huge suprise. Still, the boiler would work using the rocker switch and I could get hot water and heating as required.

Anyway, just before New Years' Eve, the boiler started making a strange "splashing" noise then would lock out after about 20-30 seconds. After phoning Baxi up, they sent an engineer out as it was still covered by the guarentee, which was nice. When he got here, he'd discovered about 1/2 a bucket of water sat in the flue extraction pipe which was causing it to lock out.

Now the engineer said that there was water somehow getting into the flue either through condensation or from rain water making it's way in some how.

So I was wondering, do the flue pipes that go through my loft need lagging? I asked a work mate about it and he said that not all systems need lagging, but he's a bit of a know it all, and would like to know if he's right? The flue is a vertical one.

Sorry for all the spiel, but it may come in handy if someone else has the same problem

Cheers in advance

Phil

 

[Agile]

For anyone to be able to advise you we would need a fully dimensioned description of the flue routing ideally as a drawing.

Does your boiler ever do "short cycling" ?

I once met a very mean owner who put his boiler on for only five minutes at a time to "take the chill" off the hot water before his wife and kids washed. The boiler was all rusty from the condensation!

So what did the Baxi engineer say and do?

Tony

 

[baxpoti]

When he got here, he'd discovered about 1/2 a bucket of water sat in the flue extraction pipe which was causing it to lock out.

The flue is a vertical one.

This dosen't add up in my book
How could half a bucket of water sit in a vertical flue

''The efficient operation of Powermax 155x will naturally give rise to condensation in the flue gases and pluming will be visible during adverse atmospheric conditions. In installations with long flue runs some condensate may be discharged from the terminal. The terminal must, therefore, be sited to avoid nuisance from either phenomenon''.

If you do have a horizontal run, it needs to be adequately supported and should fall to outside

 

[baxpoti]

Extract from the installation instructions

''Flue Pipe lnsulation
Lagging is recommended when the flue pipe length within a roof space exceeds 3m or if the flue pipe is nearly "horizontal" for more than 3m. The insulation used must be non-combustible and suitable for operating at temperatures up to 200°C. Class `O' foil backed glass wool or mineral wool duct/pipe insulation wrapped tightly around the flue pipe only will be satisfactory''.

 

[Agile]

If you do have a horizontal run, it needs to be adequately supported and should fall to outside

Does it really advise falling towards the outside? That would seem unusual for a condensing boiler.

Tony

 

[baxpoti]

Yes of course this would be unusual for a condensing boiler.

I believe we're dealing with a 155x tho!

 

[Agile]

Could this have been a mistake in the MI or would you have known if that were the case!

 

[nickso]

mine looked like it had a fall to inside.

saying that i never took the cover off in 2 years

 

[baxpoti]

Agile You've lost me!

The 155x is not a condensing boiler

There is a 150, that is a condensing powermax boiler.