Worcester 350rsf

[corgigazza]

ANy ideas were to go on this one

When ch on after 2 hours rads are cold the pump runs and the fan also

replaced ig pcb checked a.p.s checked thermistors, no found ok and fault still happens, hw sometimes also stops. to make bioler run again turn of power and is ok for 2-3 hours. if aps hose is removed and relaced while at fault it starts, have suspicians it may be the driver board

any ideas now been on it fault finding for a total of 3 hours

 

[B.O.B DOLE]

ANy ideas were to go on this one

When ch on after 2 hours rads are cold the pump runs and the fan also

replaced ig pcb checked a.p.s checked thermistors, no found ok and fault still happens, hw sometimes also stops. to make bioler run again turn of power and is ok for 2-3 hours. if aps hose is removed and relaced while at fault it starts, have suspicians it may be the driver board

any ideas now been on it fault finding for a total of 3 hours

what faults did you have before you changed the ig board what i mean is why did you change the ig board

 

[cozzmic]

I had a 350 intermittent problem, would work like yours for a couple of hours or days then start playing up no ch, hw ok the the opposite then nothing atall. Cured with the APS being changed with the main board too, if it's the one with the flashy L.E.D's in it, it was doing things that Worcester say cannot happen.

 

[corgigazza]

Repaced ig boad to cure the ch not working after 2-3 hours this did not work, same fault still present, the biggest problem here is that any fault no gas no ignition , aps not working does not bring up any fault lights and the pump and fun run only, when i arrive to fault find soon as i investigate why up its not running it bloody starts and runs with no faults.

 

[kevplumb]

you did make sure the hoses and venturi etc where ok

 

[corgigazza]

Checked hoses but not not removed fan assembly/hood only blew down them, all seemed ok and aps made and broke contact electrically ok will check venturi tommorrow ta

 

[COG]

The 350 got a couple of bad habits ,one is the main driver board can stick in an anti cycle untill you re boot the board the other is that the pilpot coil goes open circuit after a time (varies from 10mins to 4hours ) when it cools down it will go back to normal ,the trouble is you only have 7.5 seconds to find it thats the time its held open for on ignition.Check the resistanse it should be around 3.5k (i think. i usually check it against a new one )when ok and obviously open circuit when failed .The other minor prob is honywell dont do a replacement coil just the complete gas valve but red pattern ones are available. ps the 350 does not have flashing lights thats the 35cdi mk1 and mk11

 

[corgigazza]

Cheers for that, going back on friday that sounds just like the problem, have allready checked the gas valve. looks like new driver board, will let you know how it goes

 

[corgigazza]

Thursday; Fitted new driver pcb, fault still there even though unable to make it happen whilst on site, customer phoned up to say now starts first time on hw but ch still goes cold.

Friday replaced air pressure switch (took apart found no faults with it.) repaced pilot solenoid (black)240v solenoid 1.5K ohms with new (red)230v solenoid 2K ohms, also found traces of slight black stain on the case cover were the ignition lead is used heat shrink to insulate ig lead cable(baxi 100he suffer from this fault) . Removed fan & checked venturi no faults found. No call from customer yet hopefully all working.

So much for worcester tech help, told to replace ig pcb then driver pcb.
this is the first boiler I have seen that goes to fault with no indication of lockout, or were to start