Hubbell STH manual Filling The Heater, Startup

FILLING THE HEATER

1.Begin with all steam, condensate, and water valves closed.

2.Open the isolation valves on the integral circulator line ,if supplied.

3.Open cold water valve, fill unit with cold water. Lift lever on relief valve to relieve trapped air. Release relief valve lever when all traces of air have been vented from the unit. Leave cold water valve open.

STARTUP

1.Turn pump switch to the “ON” position, if supplied. (Do not operate pump without unit being filled with water and isolation valves being opened, as damage to the pump could result).

2.Set control valve thermostat to approximately 30° F below desired temperature, observe unit, if unit operates properly gradually raise set point to desired set point.

3.If unit has a safety system, set hi-limit thermostat to desired temperature. (This thermostat must be set at a higher temperature than the operating thermostat or the unit will never reach the desired temperature). Refer to the enclosed piping and wiring drawings.

4.Gradually open valve to allow heating medium to enter the heating element. (Boiler water lines should be vented to eliminate trapped air). Monitor the tank temperature until the desired temperature is reached. If the temperature regulator shuts off before the desired temperature is reached, or if over-shoot occurs, adjustment of the temperature regulator will be required. (Refer to enclosed O&M manuals for your specific control valve).

5.After control valve adjustments have been made and the desired temperature has been reached, open the valve on the hot water outlet and the building recirculation line.

6.Tightening of some gasketed joints may be required after unit has been heated.

7.Never break any joint, gasketed or screwed on unit until the pressure in the unit has been reduced to zero and the unit drained.

8.Observe operation of unit for 30-40 minutes after initial start up.

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