I am having trouble with an old wall mounted Junkers instantaneous hot water service. I am sure that the diaphragm which operates the gas flow valve is faulty. I do not know where to buy a diaphragm.
the heater is old, but still in good condition. It would be from @ 1960 and has white enamel casing and funnel type flue. Makers plate indicates a 2 gal/min model with serial No. DNG 250 M1/11 S14; It was made at factory No. 503, Germany.
The unit played up recently, would light, give luke warm water until the flame died down after @ 2 minutes. I have pulled the unit apart and found a sticky spool valve needle; regreased it and reassembled. Heater will now run for 3 minutes and water is seeping from the pilot/full light swivel handle control; Obvoiusly the diaphragm in the base water valve is carcked and building up back pressure after several minutes running?
Where would I be able to buy a new diaphragm for this type of water heater? Please advise if known, I live in Melbourne Australia, does anyone know of a supplier of Junker diaphragms. Spool valve is also worn and could do with changing if available also,
Junkers water heaters are very very similiar to those made by Bosch, in fact I have used the same parts between each. I would suggest you contact Robert Bosch Ltd or their agent in your City and see if they can supply a water diaphram and a spindle valve for your unit.
I will warn you in advance they will require the full model details of your existing unit to enable them to match up the parts you need.
Thanks for the lead, I will do so. The information regarding serial number is the only indication on the heater chassis; these units were as common as mud when I was a kid, I should have some luck as many are still in use,