Vaillant vcw sine CH & DHW luke warm

[Shamus]

Hi everyone

When i turn the tap or the heating on the boiler fires up but the flames inside are noticably smaller than i seem to remember, maybe about an inch instead of inch & half with an orange tinge to the tips. The hot water is luke warm and the rads don't get very warm either. I've bled at all the required places. Any help would be appreciated

cheers
Shamus

 

[chrishutt]

Sounds like it might be a problem with the NTC resistor (thermistor). Simple to check - pull off lead briefly (must be replaced) and see if flames rise to normal size. If so, the NTC resistor is a cheap spare and easy to replace (dry mounting) on this boiler. You'll need the manual if you're thinking about doing this yourself.

 

[DP]

It is not the ntc.

Need to be in front of the boiler to establish the cause. Difficult boiler to diagnose remotely

 

[bripl]

i would be very surprised if it was the ntc as dp has said you need to be in front of it,the clue is in the orange tinge

 

[chrishutt]

OK, so the NTC thing was a shot in the dark (I did say "might"). I guess it's got to be a Corgi job then?

If your looking for an engineer, make sure they are familiar with this type of boiler. A lot won't have a clue and will just tell you to get a new boiler. Do you give your location?