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Andrew Smith
Andrew Smith, HVAC Technician
Category: HVAC
Satisfied Customers: 3756
Experience:  Heating and Controls engineer
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My Vaillant 428 bangs when achieved set temperature or switching

Customer Question

My Vaillant 428 bangs when achieved set temperature or switching off
Submitted: 4 years ago.
Category: HVAC
Expert:  canuck the pro replied 4 years ago.

canuck the pro :

Hi, my name is Mike and I have been in the home improvement and repair field for 20 years. I will be glad to help you today. I am sorry you are having troubles with your system. Let's work it out. Would you please tell me what your current system pressure is?

JACUSTOMER-r174m535- :

This not a combo boiler

JACUSTOMER-r174m535- :

Sorry I mean combi boiler

JACUSTOMER-r174m535- :

An ecoTEC plus hung open vent condensing boiler

canuck the pro :

I am sorry for my delayed response. I will still be away for several more hours so I will opt out so other experts can help when I am away. If no other expert has responded I will opt back in. Sorry about that. Mike.

Expert:  Andrew Smith replied 4 years ago.
How does it perform normally - are you getting kettling from the appliance when running?
Do you have the approximate age?
Customer: replied 4 years ago.

No, I do not have any kettling, no problem with hot water, on and off, just 'heating ' bangs when system is switching off ! No other problems

Customer: replied 4 years ago.
Relist: Incomplete answer.
Expert:  Andrew Smith replied 4 years ago.
Does the heating still take the normal amount of time to heat, or is it getting longer?
Customer: replied 4 years ago.

No problem with achieving temperature, just bangs when achieved

Expert:  Andrew Smith replied 4 years ago.
I wonder if it is not modulating?
Is there a viewing window on your model?
If so can you see if the flames get smaller when the system is hot?
Customer: replied 4 years ago.

I am sorry for delays in replying, 'working!'

Unfortunately there is no window. The boiler is approaching 5 years old.

Heating takes normal time to heat, it is not taking any longer.

Expert:  Andrew Smith replied 4 years ago.
Ok, I suggest we just monitor for the next 24 hours