Water Heater User Manual

f. Apply air pressure to valve diaphragm so that stem halves are aligned and re-connect

stem halves.

g. If valve will not open with air on the diaphragm, spring tension should be decreased.

h. Adjustment is essentially the same as if spring tension were increased except the

adjustment screw is turned in the opposite direction.

5. ADJUSTMENT OF PILOT OPERATED VALVES

a. Pilot operated valves such as Spence or Spirax/Sarco are not fail safe. These valves have

a liquid or gas filled thermo-static bulb and if this bulb loses its charge, the valve will go

to its full open position and cause overheating of the water heater. This situation should

be considered before attempting to adjust these valves.

b. Spirax/Sarco Valves

are completely pre-set at the factory and there is no spring

adjustment. Set the thermostat at the desired temperature and no further adjustment is

required.