Worcester 28i rsf Overheating switching itself off

[Inverness]

problems with combi, heating control thermostat doesn’t seem to click off when you turn the knob to min after it’s been on for 10mins? Also the customer says the boiler switches off after 20mins but the high limit hasn’t been activated?
Hot water is fine just the heating overheating and switching it’s self off?
I’m a new gas engineer so be kind please.

 

[Aire]

I’m a new gas engineer so be kind please.

I know how you feel so much to learn.

When the customer says the boiler switches off after 20 mins, do they mean the boiler locks out or just the burner only runs for 20 mins then fires back up again after a few minutes?

 

[ShaunCorbs]

What's the flow temp getting too

Is the pump the original?

 

[Inverness]

Standard grundfos pump runs ok.customer says the boiler cuts out so they then need to turn it own manual with the programmer. But the high limit button hasn't been activated. But I noticed the front control thermostat dial doesn't respond with moving it to minimum to maximum?

 

[Inverness]

The flow temperature I can just keep my hand on it and no more. I never checked the temperture but the radiators where heating up good.

 

[Chuck]

I’m a new gas engineer so be kind please.

I think you'll find the installation and servicing manual has the info you need:

https://www.worcester-bosch.co.uk/support/literature/download/release/8716145299/12832

@ShaunCorbs - Should this thread be moved to a closed forum?

 

[ShaunCorbs]

I think you'll find the installation and servicing manual has the info you need:

https://www.worcester-bosch.co.uk/support/literature/download/release/8716145299/12832

@ShaunCorbs - Should this thread be moved to a closed forum?

Didn't spot it was in the open

 

[Inverness]

I figured it out expansion vessel Damned and losing pressure and gauge is clogged up. I think it's been running with low pressure and cutting out? Firstly I'll fix a new guage and expansion vessel and see how thing perform.