Vaillant Turbomax 828 Flue problem - a bit long winded but bear with me
The above boiler was installed around 10 years ago. Have had a variety of replacement parts, diverter valves, new fans, switches, etc. It has been regularly serviced by Vaillant for the first few years and has been under a British Gas contract for the last 6 years. Magnaclean fitted to system a few years back (not by BG). Had a problem latter part of last year and BG sonically cleaned the secondary heat exchanger at the same time. Despite the numerous replacement parts I can't fault the heating / hot water supply.
Unfortunately, on refitting the heat exchanger the seals weren’t good and just had to call BG out as boiler wouldn't fire up. 3 small leaks were identified where heat exchanger had been removed with water dripping into PCB so new PCB, re sealed the leaks and changed a valve just in case.
All looked good but engineer couldn't get it to pass emissions. Came back following day and cleaned it thoroughly but still too high. Thought may be a block in flue so took it to pieces and found a problem with one of the seals. Couldn't get new seals so bought new flue system to pinch seals from it. Still no joy. I'm sure the experts have guessed the next step. Checked the flue length, vertical flue, comprising 2 x 45 degree bends (100cm) , a 90cm and 75cm straight and the straight going out of the roof coming to about 3.6m which is apparently about 40cm too long!
I can't fault the engineer as rather than leave and say the flues too long he then ordered a new fan and fitted it the following morning. Thankfully this did the job and emissions were within the acceptable limit. Left a notice saying not to current standard and all currently OK.
The question is what do you advise I do about the flue. I could probably have the existing 100mm flue moved a few roof tiles and just about lose the 40cm but I would be close to a roof valley and closer to the eaves. Is this a problem and can you cut Vaillant flues.
Would a new 125mm flue be a solution as I understand this can go higher but is it compatible with the boiler. Having seen the cost I think I'd prefer to stay with the 100mm.
I could do nothing as it's been like it for 10 years (Vaillant or BG never identified it as a problem before) and assume the life of the fan is around 3 years although this worries me. We have a couple of detectors near the boiler and in a loft extension but neither has ever been triggered.
Any advice would be appreciated.
The above boiler was installed around 10 years ago. Have had a variety of replacement parts, diverter valves, new fans, switches, etc. It has been regularly serviced by Vaillant for the first few years and has been under a British Gas contract for the last 6 years. Magnaclean fitted to system a few years back (not by BG). Had a problem latter part of last year and BG sonically cleaned the secondary heat exchanger at the same time. Despite the numerous replacement parts I can't fault the heating / hot water supply.
Unfortunately, on refitting the heat exchanger the seals weren’t good and just had to call BG out as boiler wouldn't fire up. 3 small leaks were identified where heat exchanger had been removed with water dripping into PCB so new PCB, re sealed the leaks and changed a valve just in case.
All looked good but engineer couldn't get it to pass emissions. Came back following day and cleaned it thoroughly but still too high. Thought may be a block in flue so took it to pieces and found a problem with one of the seals. Couldn't get new seals so bought new flue system to pinch seals from it. Still no joy. I'm sure the experts have guessed the next step. Checked the flue length, vertical flue, comprising 2 x 45 degree bends (100cm) , a 90cm and 75cm straight and the straight going out of the roof coming to about 3.6m which is apparently about 40cm too long!
I can't fault the engineer as rather than leave and say the flues too long he then ordered a new fan and fitted it the following morning. Thankfully this did the job and emissions were within the acceptable limit. Left a notice saying not to current standard and all currently OK.
The question is what do you advise I do about the flue. I could probably have the existing 100mm flue moved a few roof tiles and just about lose the 40cm but I would be close to a roof valley and closer to the eaves. Is this a problem and can you cut Vaillant flues.
Would a new 125mm flue be a solution as I understand this can go higher but is it compatible with the boiler. Having seen the cost I think I'd prefer to stay with the 100mm.
I could do nothing as it's been like it for 10 years (Vaillant or BG never identified it as a problem before) and assume the life of the fan is around 3 years although this worries me. We have a couple of detectors near the boiler and in a loft extension but neither has ever been triggered.
Any advice would be appreciated.
