Hi anyone. I have the F28 code on this unit. Gas IN is fine and on start up fires but within a second or two, the gas valve shuts. Taken the valve apart and the diaphram is ok,no splits.
S code runs thru 1, 2 & 3 but will not progress to 4( burner ignited). Checked the low voltage solenoid and getting 35 V1 & 17.8 V2(53 Ohms across 2 outer pins). Vaillant say in their opinion it is the pcb but having changed it, the problem remains. The fan gives 418-420 rpm reducing to 380, again vaillant say this ok for initial start and within 10% range.
I've also changed the sparker & ioniser and had the burner out,inspected & cleaned. The 2 connections to gas valve give me 21.8v reducing to 15 then zero, now. Could this gas valve in fact be faulty, even tho the solenoid readings say otherwise?
continuity runs thru all connections and earth is good!
Anyone know where to look next, other than blind replacement?
I have a noodle, and it's being Baked!
Thanks for any help.
PS.. only just registered so not allowed at this point to access the gsr private advise forum.
S code runs thru 1, 2 & 3 but will not progress to 4( burner ignited). Checked the low voltage solenoid and getting 35 V1 & 17.8 V2(53 Ohms across 2 outer pins). Vaillant say in their opinion it is the pcb but having changed it, the problem remains. The fan gives 418-420 rpm reducing to 380, again vaillant say this ok for initial start and within 10% range.
I've also changed the sparker & ioniser and had the burner out,inspected & cleaned. The 2 connections to gas valve give me 21.8v reducing to 15 then zero, now. Could this gas valve in fact be faulty, even tho the solenoid readings say otherwise?
continuity runs thru all connections and earth is good!
Anyone know where to look next, other than blind replacement?
I have a noodle, and it's being Baked!
Thanks for any help.
PS.. only just registered so not allowed at this point to access the gsr private advise forum.
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