Johnson & Starley Eljan 6: solenoid buzz

[Clive Backham]

I have a Johnson & Starley J50 warm air heating unit, with an Eljan 6 water heater built-in. It was installed about 3.5 years ago. Straight away, there was a problem with the solenoid on the Eljan 6 buzzing, so it was replaced under warranty. Recently the buzz returned, and of course the unit is well out of warranty. Sometimes if you switch the water heating off & on again, the buzz is reduced or eliminated, but every time it switches on via the clock, the buzz comes back. It's getting pretty irritating, and having heard horror stories about spare parts prices, I'm wondering if anyone has any suggestions for alternative remedies other than just paying for another solenoid (which we can presume will become noisy again in 2 or 3 years). Is there some sort of modification I can make to the solenoid to quieten it? Could the buzz be caused by a dirty mains supply, in which case would some kind of mains filter do the trick?

[Dave Plowman]

If it were mine, I'd investigate running it off DC - a solenoid which works on AC will also work on DC. But simply rectifying the AC might result in overheating it - I'd experiment to find the lowest DC voltage it works on reliably.

[Pete C]

Hi,

The buzzing is almost certainly due to loose windings in the solenoid. How much is a new one?

cheers, Pete

[John]

The buzzing is more than likely due to poor seating of the moving armature within the coil. If it had been an electrical contactor cleaning the armature and yoke faces would probably have been all that is necessary to eliminate the noise, however this is not normally considered an accessible part on a gas solenoid and you should replace the unit. It might be worth just making sure that the coil is not loose on the mount before you do so.

[Clive Backham]

OK, thanks for the advice.