Vaillant boiler vibrating cold start

[jonnyp]

Vaillant ecomax 18e boiler noise at cold start.

Replaced heat exchanger with reconditioned unit and new flue collector as kettling was getting problematic. Works fine except vibrating for around 10 seconds on cold start. Didn't do it before. Any ideas?

 

[ShaunCorbs]

Are you the homeowner?

 

[jonnyp]

Are you the homeowner?

My daughter is.

 

[ShaunCorbs]

My daughter is.

Whose replaced the parts you?

 

[jonnyp]

My daughter is.

Whose replaced the parts you?

No. gas engineer neighbour. He seems puzzled by the noise. He also serviced the boiler about a month ago and was fine then apart from the kettling. Like I say it runs fine other than the resonance vibration for 10secs or so when first starting up. Don't want to throw much more money at it 14 years old now.

 

[ShaunCorbs]

Get the gas engineer to loosen the case mounting hex bolts 1/2 a turn

 

[jonnyp]

Get the gas engineer to loosen the case mounting hex bolts 1/2 a turn

Thanks for the suggestion. It even makes the noise when he took all the panels off exposing the heat exchanger. Does he need to service it again now that he's replaced the flue collector and heat exchanger? Could the gas mixture have changed?

 

[ShaunCorbs]

He should of checked it

I suspect the bolts are tight vaillant did a tb a few years ago saying you need to loosen then and install copper grease due to problems with noise I’m guess as it was second hand it didn’t come with this information

 

[jonnyp]

That's interesting. Do you mean the flue collector bolts, heat exchanger or case?

 

[ShaunCorbs]

Heat exchanger mounting bolts

 

[jonnyp]

Heat exchanger mounting bolts

Great thanks I'll pass that on. Do you have the tb reference that I can give him. I'm tempted to get someone else in to do a service and check the mix.

 

[ShaunCorbs]

Sorry I don’t but @king of pipes @ChrisB1982 might

 

[jonnyp]

Great thanks I'll pass that on. Do you have the tb reference that I can give him. I'm tempted to get someone else in to do a service and check the mix.

Sorry I don’t but @king of pipes @ChrisB1982 might

Very much appreciated. I've messaged them. Fingers crossed.

 

[Deleted member 120897]

Sorry I don’t but @king of pipes @ChrisB1982 might

No, I don’t sorry. If not KOP then @EvilDrPorkChop might?

 

[EvilDrPorkChop]

No, I don’t sorry. If not KOP then @EvilDrPorkChop might?

No sorry I don't either.

 

[jonnyp]

Unable to track down the tb but have had a response from vaillant. The grease is to stop creaking and clicking noise which isn't the problem but the spec for tightening the nuts is only 6nm which I guess he overtightened with the water pump pliers he used. I noticed he also didn't replace the nuts with the new ones supplied with the flue collector. Not sure if that's important enough to get him to change when he loosens them.

Many thanks for your help. I'll post the outcome.

 

[jonnyp]

Unable to track down the tb but have had a response from vaillant. The grease is to stop creaking and clicking noise which isn't the problem but the spec for tightening the nuts is only 6nm which I guess he overtightened with the water pump pliers he used. I noticed he also didn't replace the nuts with the new ones supplied with the flue collector. Not sure if that's important enough to get him to change when he loosens them.

Many thanks for your help. I'll post the outcome.

Boiler now much quieter. Plumber loosened heat exchanger clamps slightly which helped but richening the gas mixture from 8.1% to the specified 9.1% seems to have resolved it many thanks to shauncorbs for his advice

 

[jonnyp]

Very much appreciated. I've messaged them. Fingers crossed.

Boiler now much quieter. Plumber loosened heat exchanger clamps slightly which helped but richening the gas mixture from 8.1% to the specified 9.1% co2 seems to have resolved it. Many thanks for your advice