Hoffman ELG-4 - Adjusting Steam Pressure Settings; Thermostat Control for Pressure; Replacing the Thermostat Component

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JEL3 TECHNICAL MANUAL
PROBLEM POSSIBLE CAUSE CORRECTIVE ACTION
Water is dark
brown or black.
Rust in Water.
See Section 4.3 – Blowing Down the
Boiler. Rust is a normal occurrence
in steam generator shells. The rust
appearance in the water will slowly
disappear after a few weeks of use. The
steam generator must be blown down
in accordance with instructions given in
this manual. Blowing down will minimize
the visual amount of discolored water.
No steam
comes from the
Solenoid Valve.
Bad Foot Switch.
Check Switch. See Section 5.7 –
Replacing the Electric Foot Switch.
Bad Solenoid Valve.
Replace. See Section 5.10 – Replacing
the Electric Solenoid Valve.
Can not ll with
water.
Breather valve not
open.
See Section 3.0 – Operation.
Check Valve is
stuck.
Lightly tap valve.
Clean valve seat. Disconnect power
and remove pressure from the boiler.
Check no pressure by leaving the
breather open.
Replace valve.
Water Inlet
Solenoid Valve fails
to operate.
Replace Water Inlet solenoid Valve.
Boiler keeps
lling.
Inlet solenoid Valve
is dirty.
Clean seat in Solenoid Valve. WARNING:
Disconnect Power before servicing.
Drain Boiler.
Wet Steam.
Too much water in
Boiler.
Drain tank until water level lls sight
glass approximately 75%.
Hard to see
through the
Sight Glass.
Minerals have
coated the glass.
Clean or replace. See Section 4.2 –
Cleaning the Sight Glass or Section 5.4
– Replacing the Gauge Sight Glass.
5.2 ADJUSTING THE STEAM PRESSURE
5.2.1 THERMOSTAT CONTROL
1. Power the boiler.
2. Turn the thermostat to “10.”
3. Allow the boiler to come up to pressure.
4. Remove the dial from the thermostat.
5. Using a small screwdriver, turn the screw inside the stem clockwise to
reduce the pressure, counter clockwise to increase the pressure.
6. Turn the stem in ¼ turn (90 deg.) increments. Allow the unit to heat or
cool. The nal high pressure is reached when the heating light goes out.
7. Use a dab of nail polish to secure the screw in position.
8. Put the dial back on the thermostat.
9. The maximum pressure setting shall be 90 psig. Attempting to raise
pressure higher will result in relief valve venting.
10. All eld wired units are supplied with a knock-out sized to UL
specications. Inside the electrical panel is a wiring schematic for
power and ground connections.
5.3 REPLACING THE THERMOSTAT
(To be performed by a licensed electrician)
1. Turn the power to the boiler off by pulling the plug or turning off the power at
the branch switch or circuit breaker.
2. Remove the wires on the thermostat.
3. Remove the dial from the thermostat.
4. Remove the mounting screws that hold the thermostat to the enclosure.
5. Remove the temperature sensing probe from the heating element.
6. Mount the new thermostat to the enclosure.
7. Insert the temperature sensing probe into the heating element. The sensing
probe may not go in all the way. This is normal. Insure that the sensing
tube is bent slightly up and out of the way of the heating element electric
connections. Do not kink the capillary tube.
8. Rewire the thermostat.
9. Power the steam generator. Adjustment may be necessary. If the pressure
comes too close to the safety valve rating (within 10 psig) turn the unit off
and adjust the thermostat in accordance with instructions given in this
manual.