New Vaillant Eco Tech Pro 24 clicking

[diyplumber1980]

Hi, a friend had a Vailant eco tech pro 24 installed about 6 months back. Although its brand new, and was installed by a Gas Safe engineer, the boiler makes an odd "clicking" noise when the hot water tap is opened. When central heating is on, theres no noise. Only on hot water. The noise sounds a bit like a cold central heating pipe expanding on cold mornings when you turn the rads on. Does anyone know what it could be?

 

[diyplumber1980]

http://www.youtube.com/watch?v=5lVMHDU8dAY

just found this video on youtube, this is very similar to the noise ive described. Looking at the comments below this video, seems a number of people are experiencing the same problem.

 

[Agile]

Why does your friend not call the Installer and/or Vaillant?

 

[diyplumber1980]

They have called vailant who sent someone out, but the engineer said this was normal. It clearly isnt though. The installer had advised him to call vailant.

 

[Agile]

This problem is usually solved by greasing the heat exchanger bolts and then carefully tightening them to the approved torque!

However that's a job for a gas reg engineer and not a DIY job!

Its not a very common problem on Vaillant boilers though!

Tony