vokera linea 24 DHW problem

[Maboza-Ritchy]

Hi, I have had the above combi for about 9 years and generally works well. For a little while now the DHW can be cool (luke warm) and at other times the water can be hot (the temp it should be). The DHW seems to less reliable in the mornings rather than at evening time. Can you advise what's wrong and what part(s) needs to be replaced and can someone like myself replace the part without needing a heating engineer? I'm an electrical engineer to trade (not a 6 week trained engineer).
Or should I just call out a heating engineer?

Hope you can help.

Rack

 

[Agile]

Without further information all I could guess at is that the DHW sensor is intermittently changing its value. Its cheap to change and you could do that yourself or just measure its value/temperature and see if it seems correct.

However, there are so many other possibilities, even the gas supply incoming to the house may be low at peak times so a competent CORGI is more likely to find the problem.

Tony

 

[Paul Barker]

i agree with Tony, vokera thermisters are not particularly reliable at least from that era, so well worth a punt in your position.

But we would be checking all the usual things first particulalry burner pressures. We would also have a mind on overheating causing cuting out which results in your water going cold. This could be due to sludge or due to failure of the other thermister on the primary which acts as an overheat stat during dhw function. We can identify the actual fault without trying loads of parts, but in your shoes it isn't simple so parts changing is the name of the game.

 

[nickso]

i agree with Tony, vokera thermisters are not particularly reliable at least from that era, so well worth a punt in your position.

same manufacturer as the alpha ones paul