SECTION IV – ADJUSTMENT OF TEMPERATURE REGULATORS
1.The spring tension on temperature regulators is adjusted at the factory to meet design conditions. However, design conditions may vary from actual operating conditions and re- adjustment might be required on this job.
2.Whenever possible, Hubbell uses “fail safe” regulators. This means that if the controlling medium, such as air or water is lost, the valve will close under it’s own spring tension.
3.ADJUSTMENT OF
a.Release all air pressure from the diaphragm.
b.Apply steam pressure to the valve.
c.If at this point, there is pressure on the downstream side of the valve, or if steam can be heard passing through the valve, valve spring tension needs to be increased.
d.Turn the spring adjustment screw slowly to increase spring tension until the pressure on the down stream side of the valve has dropped to “0” and there is no sound of flow through the valve. Do not turn spring adjustment past this point.
If the valve will not open with air on the diaphragm, spring is adjusted too tightly.
(1)Release all air pressure from the valve diaphragm.
(2)Apply steam pressure to the valve.
(3)Loosen tension on the spring until steam begins to seep through the valve.
(4)Slowly, tighten spring tension until flow stops.
(5)Do not turn spring adjustment past this point.
4.ADJUSTMENT OF
a.Turn thermostat down so that no air pressure is on the valve diaphragm. If unit continues to heat, valve spring tension needs to be increased.
b.Shut off heating medium.
c.Disconnect stem coupling (A).
d.Lift lower stem (B) and hold against upper valve seat.
e.Turn adjustment screw (C) until there is approximately a
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