Baxi Solo RS 50/4

[solaman]

Boiler hasnt fired up for over a week. I have checked the pump works the motorised valve works the pilot is lit. I have drained the system and back filled the system and blew it through. there is power to the boiler thermostat(no reset on this model). Tonight I removed the timer(horstmann 425 Tiara) pulling it away from the contacts. I checked that there is power to L 2 5. I put the cover back on and the boiler fired up for about 5 minutes? I removed the timer again and exposed the contacts on the timer,I refitted it and I manually moved the contacts across to make contact but without any luck. I now believe it is the timer but not sure as everything has power any help I would be really grateful. Also some forums mention a fan, but not sure if this model has one and if it does where it is. someone said you can be lucky and free the fan off? Thanks

 

[kevplumb]

there is a reset button at the back of the control box if you remove the lower door

easiest way to check the timer is connect switched live and perm live with a link

AFTER TURNING OFF THE POWER

if the boiler fires its the clock if not its the boiler

no fan on an rs

 

[solaman]

Hi thank you for your reply. there isnt a reset button on this model.apparently it is only on the ss model of this type. I have determined which pins have power. 2 and 5 have power but i am not sure which one is switched live, beside the earth neutral and live there are 6 other terminals. 123456. of which 2 and 5 show power what terminal is switched live. thanks

 

[kevplumb]

terminals on the boiler strip

 

[solaman]

Hi Kevplumb. when I remove the timer there are 9 terminals on the back plate of which the first 8 are used. the first 3 are earth neutral and live but I dont know which other terminal to connect to the live. can you tell me which one of the 6 other terminals is switched live thanks.

 

[twgas]

If there is power to the boiler stat the problem is not likely to be the programmer. I think you'll need a RGI to check the gas side of things.
I would imagine:
term 1 HW on (supply to cyl stat)
term 2 common
term 3 HW off
term 4 CH on (supply to room stat)
term 5 common.

 

[solaman]

why do you think it fired up when I removed the timer front and refitted it. Thanks

 

[expertgasman]

there is power to the boiler thermostat(no reset on this model).

If you have 240V on the stat measured to earth or neytral, the fault isn;t yhe programmer.

i am sure there is a reat button on the back of the control box, have a good luck.

Possible faults:

T'stat not switching
piggy back tags not fully conecte (Gravity system)
Faukty O'h stat (should be by passed on gravity systems, see above
Neutral fault
Gas valve

All pretty straightforward, an RGI should determine within 15 mins

 

[solaman]

Thank you for your help. I shall investigate further

 

[solaman]

Thank you TWGAS and Expertgasman for your help. I had a gorgi guy out and it turns out it was the gas valve. Hopefully have it fitted by Monday or Tuesday.Just as well it hasnt been cold!