I just moved into a new house and it has a Baxi 105e boiler. The hot water works fine but the central heating doesn't. There are no warning/fault light being displayed. I had a plumber look at it and he couldn't find anything wrong but said that the fault cold be the circuit board. He did manage to get the boiler to fire up by removing and then reconecting one of the sensors but the boiler stops after the 30 degree led illuminates???? Has anyone experienced this issue? Someone please help.
Baxi 105e HW works fine but CH dosn't??? HELP!!!
- Thread starter guvnagra
- Start date
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OK so it isn't external controls it works up to 30 degrees.
It isn't oh stat because if he undid that the boielr wouldn't work.
He must have undone the thermister, I never knew they would work without a thermister most boilers must have one in an expected range or they won't even begin to work.
Looking like new thermister for starters.
gtpe will know better
It isn't oh stat because if he undid that the boielr wouldn't work.
He must have undone the thermister, I never knew they would work without a thermister most boilers must have one in an expected range or they won't even begin to work.
Looking like new thermister for starters.
gtpe will know better
N
namsag
The sensor that is fitted beside the plate heat exchanger is the usual cause of a no heat fault and requires changing
When i disconect the central heating sensor and reconect it the boiler fires up and heats the water to 30 degrees before the boiler turns off. I tried switching the DHW sensor with the CH sensor by just swaping the conections around to see if the CH sensor was faulty but the problem still remained. One thing i did notice is that if i remove the connection for the DHW sensor the Fault on Hot Water Sensor led sarts to flash but if i remove the connection to the central eating sensor no led flashes. Could this be a fault on the circuit board??? A local shop sells the PCB for £78, i'm wondering if i shold just change it and see.
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N
namsag
Instead of changing the leads swap the sensors over . This will confirn fault usually.
This is true but in this day and age it is sensible to stock thermisters and just change them, by the time you darin boiler just to swap them you might aswell change them for the few quid they cost.
On many boilers that is very likely all you need to do.
On many boilers that is very likely all you need to do.
N
namsag
Agreed Paul only told him this to cofirm fault and not change pcb without it being boll#xed. Personally would change sensor for reasons you give.
Sorry to butt in, i am having grief too.
Can you confirm that when you talk about 'sensors' and 'thermisters' you are talking about the same thing?
Cheers
Can you confirm that when you talk about 'sensors' and 'thermisters' you are talking about the same thing?
Cheers
You are butting into a 12 mointh old discussion!
On most boilers an NTC thermistor is used as a temperature sensor.
The problem in this thread may have been a faulty PCB although the gas valve minimum gas setting should have been checked first as many PCBs are changed when the only problem is the gas valve setting.
Tony
On most boilers an NTC thermistor is used as a temperature sensor.
The problem in this thread may have been a faulty PCB although the gas valve minimum gas setting should have been checked first as many PCBs are changed when the only problem is the gas valve setting.
Tony
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