Vaillant Turbomax VUW boiler won't fire up - tries to but stops and
then on/off light flashing. Manual just says this indicates the
overheat themostat. Is this likely to be a failed part or something
bigger? I can't reset it from the controls.

In article 202009261058296454-nospam@nospamcom,
John Smith wrote:
Vaillant Turbomax VUW boiler won't fire up - tries to but stops and
then on/off light flashing. Manual just says this indicates the
overheat themostat. Is this likely to be a failed part or something
bigger? I can't reset it from the controls.

overheat thermostats do fail - happened to me once - different boiler
though.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

John Smith wrote on 26/09/2020 :
Vaillant Turbomax VUW boiler won't fire up - tries to but stops and then
on/off light flashing. Manual just says this indicates the overheat
themostat. Is this likely to be a failed part or something bigger? I can't
reset it from the controls.

Have you checked to ensure the water is ciirculating through the
boiler? Check the pump actually runs and is not seized. Remove the
shaft end cap and check the shaft is spinning, if not it might be
seized - use flat bladed screw driver to turn it and free it.

On 26 Sep 2020 at 10:58:29 BST, "John Smith" wrote:

Vaillant Turbomax VUW boiler won't fire up - tries to but stops and
then on/off light flashing. Manual just says this indicates the
overheat themostat. Is this likely to be a failed part or something
bigger? I can't reset it from the controls.

Could it be a flame detection device? I haven't looked up what kind your
boiler has, but they are usually more-or-less easily replaceable.

--
Roger Hayter

So boiler guy reckons it's the PCB as all else is working as it should
- just not receiving the right signals.

A new one is £200 from main suppliers. But ebay has new ones at about
£40 - are these really genuine parts. I guess I'd have to fit it myself
as company probably won't touch them.

https://bit.ly/3kVFOx2

https://bit.ly/3j6ugqi

On Mon, 28 Sep 2020 18:03:50 +0100, John Smith wrote:

So boiler guy reckons it's the PCB as all else is working as it should -
just not receiving the right signals.

A new one is £200 from main suppliers. But ebay has new ones at about
£40 - are these really genuine parts. I guess I'd have to fit it myself
as company probably won't touch them.

https://bit.ly/3kVFOx2

https://bit.ly/3j6ugqi

Try this guy. Used to be in this group and is well thought of.

https://www.cetltd.com/



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