BAXI 400 heat fault

[Alan12]

I have a baxi 400 heat boiler, was working perfectly then suddenly boiler stopped working
When I go to the boiler, there are two lights on the front of the panel. The RESET light is solid green, and the "chimney status" light flashes with 1 intermittent green flash every few of seconds.
Any one have any experience with this error? I have looked in the instruction manual, and it says this error is due to a "temperature protection issue" - either due to "maximum flow temperature exceed, flow temp rise rate too high, or excessive difference between flow and return temperature". Why would this happen, and what do I need to do to fix it/stop it happening again?

 

[Jurassicspark]

Is there a bypass installed on your system?

Whats the flow temp set at?

 

[Alan12]

Flow temp set at 70
No bypass valve as far as I can see (photo of piping below).
When I turn the controller for heating on, the boiler turns on (audibly and the lights turn on appropriately), then after about 30seconds, you can hear the boiler turn off and the error lights flash as described.

 

[CountryFan]

If it’s overheating (which it sounds like it is) it can point to:

Circulating pump
Motorised valve (not opening at all or fully)
Lack of water in feed and expansion cistern if you have one

 

[CountryFan]

Flow temp set at 70
No bypass valve as far as I can see (photo of piping below).
When I turn the controller for heating on, the boiler turns on (audibly and the lights turn on appropriately), then after about 30seconds, you can hear the boiler turn off and the error lights flash as described.

That doesn’t be show much unfortunately, just the gas pipe and the base of your boiler

 

[Alan12]

That doesn’t be show much unfortunately, just the gas pipe and the base of your boiler
View attachment 372412

Thanks, theres a pic above and below. One is gas pipe, other is water pipes.

 

[CountryFan]

Thanks, theres a pic above and below. One is gas pipe, other is water pipes.

I could only see one photo before. Just make sure those filter isolation valves are ope, if you look at the chrome plated flat bit, should say whether on or off.

 

[gas112]

checking the pump should be your first point of call

 

[Alan12]

thank you.
It was the pump, been replaced and back in business.