Baxi 80e combi boiler hot water no heating pls help!

[coldtofreezing]

Hello everyone, I have found this forum and hope someone may be able to help me...
I have a baxi combi boiler 80e , it has always been fine it is 7 years old, i turned the heating off in the spring and have been on DHW ever since, last week put it onto water/heating mode and absoutely nothing.
The hot water is still working fine on both settings ie on tap symbol and tap/heating symbol, there is just no sign of heating, no failure lights are flashing, pressure is fine, the thermostat in the room has been checked by an electrician and is calling for heat with correct voltages, theres just nothing happening on the boiler, the main green on switch is lit, i wondered if anyone had any suggestions before i spend out on a pcb board/engineer as i have read so many posts that say changing the board didnt help, many thanks for your time, as my user name suggests we are getting very cold! thanks mandy.

 

[coldtofreezing]

just to add only the green 'on light is coming on, the green radiator light is not.

 

[coldtofreezing]

also the pump seems to be free, we took the screw out and could turn it by hand freely, anyone pls help?

 

[coldtofreezing]

We have checked some micro switches but are not sure where everything is located and it is so fiddly to get your hands into the bit where the pipes are, any help would be much appreciated.

 

[baxpoti]

just to add only the green 'on light is coming on, the green radiator light is not.

Have you a room stat or other time controls external to the boiler?

What time controls do you have?

 

[coldtofreezing]

Hi in the hallway there is a 'baxi heating' external thermostat box, new batteries in it, and it clicks and the flame symbol appears (caling to the boiler for heat right??), once a while back the boiler wouldnt start was dead and it was because the box was on auto (this was when i had just moved in and didnt realise the previous owner had set it to come on and off) i pressed it to manual and straight away it came on...that was back then, so this time the first thing i did was check it was on manual and it is definately cold enough in here for it to ask the boiler for heat, i have just looked at it again and the flame symbol is still there but the boiler is doing nothing, no fan noise, no pump noise just nothing. thanks so much for replying.

 

[baxpoti]

You need to eliminate external timers/controls and roomstats

Get a competent person to switch off power to boiler remove outer case and drop down the front panel.

Remove small white panel on the left hand side where the mains wire goes in.

Locate terminals 1 and 2

Remove any wiring on these terminals and link 1 and 2

Put back together and switch boiler on for heating

 

[coldtofreezing]

we have done exactly as you said, step by step - absolutely nothing, just as i described earlier the green neon 'power on' button is illuminated but nothing else is happening at all.

 

[kevplumb]

View media item 14646
wiring

 

[baxpoti]

I presume the hot water light does go off when tap is switched off?


If you have linked together terminals 1 and 2 and hot water is Ok in both positions then (unless someone has had their fingers in messing about) a PCB is probably required.

 

[coldtofreezing]

many thanks for the diagram, it confirms we have put the link wire in the right place as advised, but it hasnt made any difference , the boiler is still the same, just the power light is working, i switched it to DHW in the spring and has not been put onto CH until now, the boiler has been undisturbed not knocked or banged etc through the summer months.

 

[coldtofreezing]

thanks again for taking the time to reply i really appreciate your help, right, the link is still in place i put the hot water on in both positions, in both positions the green light comes on boiller activates etc, turn the tap off the green light goes out, no one has pulled any wires off etc (only this link thing now) and the boiler has been untouched all summer only on DHW, i did wonder if it might be that pcb board as there are so many little wires-transisters etc on it, do you think it has just burnt out on one section hence why hot water no heat??
Thanks again.

 

[Jezzy]

Manual is saying its the pcb, but it is usually the diverter valve stuck in the hot water mode in most cases. Just thinking that it could be the diaphragm split and giving hot water only. HW will be the default position. Page 35 and 36 in the manual.

 

[baxpoti]

usually the diverter valve stuck in the hot water mode in most cases.

But the hot water light goes on and off with demand and the c/h light does not come on

 

[coldtofreezing]

Hi again, we seem to be on a downward spiral with this boiler, have today been and bought a new pcb board and fitted it (£97!)- it is slightly different to my old one as the part number changed from 248074 to 5112380 (it is meant for baxi 80e combi) have switched it on and now the following has happened,
the power green light is on, when turning the tap on the water symbol comes on and immediately after this the lights under numbers 30 and 40 flash together, i put it to central heating and water it tried to kick in and made the noise like when it usualy starts up, then cut off and the lights under 30 and 40 flash, now both neons under 30 and 40 stay flashing when you are not asking the boiler to do anything.
Have turned the re-set button and it doesnt change anything as soon as you ask for water or heat they flash again, i have dug out the manuall and it says safety heat thermostat activated ????, pls help was so disappointed when the heating didnt come on, thanks to you all for your time and help with this.