Baxi no heating, Hot water ok ???

[coltheplumb]

OK here's one for you all, Baxi Duo Tec 28 Combi, Hot water works fine no change, Heating wont kick in ?( first time trying heating after summer), NO Error codes, Programmer checked, pump checked, diverter checked, changed Heating Thermistor, keeping in mind hot water works fine, Green heating light comes on for about 30 seconds but boiler doesn't fire up, I did try turning up room stat and run hot water for a short time, This did work once only and heating ran on working once tap was turned off, but this trick hasn't worked since ?? any ideas anyone??

 

[CountryFan]

Who's checked the diverter? Is the selector switch on heating and hot water?

 

[gas112]

from rest when you turn up room stat does the c/heating demand light come on , you say it does for 30 seconds
Does the boiler do anything in that 30 seconds ie pump fan run ?

 

[coltheplumb]

I stripped the diverter down and checked it wasn't stuck, i also turned it on to make sure the motor ran and watched the pin in the motor move up and down.
Yeah once the green light comes on for 30 seconds the boiler goes into fire up mode and the pump runs, plus you can hear the motor for diverter working, i even changed the thermistor ,

programmer and room stat work as i use those to get it running ????

 

[CountryFan]

Does the temperature ramp up?

 

[gas112]

I stripped the diverter down and checked it wasn't stuck, i also turned it on to make sure the motor ran and watched the pin in the motor move up and down.
Yeah once the green light comes on for 30 seconds the boiler goes into fire up mode and the pump runs, plus you can hear the motor for diverter working, i even changed the thermistor ,

programmer and room stat work as i use those to get it running ????

you say fire up mode , so does it actually fire .
not by any chance turned off the boiler isolating valves by mistake when filling up also sometimes if they have been used lever just spins on spindle and needs taking off and turned on with pliers

 

[coltheplumb]

No when i call for heat on the room stat, the green light comes on for about 30 seconds , pump starts, fan starts, pizo clicks but boiler doesnt light, while thats taking place the green light goes off, all valves are on,
The heating was working fine last year, then we didnt use heating during summer, but still used hot water, when we turned heating on this year I had the problem ????, Just drained down and removed it as decided to but a new one tomorrow, ( it was 10 years old) , cant cope with wife bashing my ear every morning telling me she's cold (we have a woodburner in the lounge anyway

 

[CountryFan]

No when i call for heat on the room stat, the green light comes on for about 30 seconds , pump starts, fan starts, pizo clicks but boiler doesnt light, while thats taking place the green light goes off, all valves are on,

After that does the sequence restart or just go idle?

 

[gas112]

No when i call for heat on the room stat, the green light comes on for about 30 seconds , pump starts, fan starts, pizo clicks but boiler doesnt light, while thats taking place the green light goes off, all valves are on,
The heating was working fine last year, then we didnt use heating during summer, but still used hot water, when we turned heating on this year I had the problem ????, Just drained down and removed it as decided to but a new one tomorrow, ( it was 10 years old) , cant cope with wife bashing my ear every morning telling me she's cold (we have a woodburner in the lounge anyway

if piezo clicks and lights for HW IF it doesnt for CH it could only be a board fault

 

[CountryFan]

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