Munters HCUw, Эксплуатация и техническое обслуживание

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Safety controls: NEVER BYPASS A SAFETY DEVICE. DOING SO COULD RESULT IN PROPERTY
DAMAGE, INJURY, OR DEATH.
Pressure switch.
If the draft motor does not start, or if the flue vent is blocked, the pressure switch will prevent
the ignition controls and gas valve from being energized.
Limit Switch. If the circulating air temperature should become greater than 185°F the limit switch will turn off the
ignition controls and gas valve. This switch will automatically reset at approximately 165°F.
Roll Out Switches . These switches will turn the ignition controls and gas valve off in the event of sustained flame
roll out which causes a temperature of 225°F on the top of the appliance. These switches will automatically reset.
Flame Sensor.
This is a flame rectification circuit. This sensor deteiuiines if the burner nearest to it is lit. If the
burner is not lit, the ignition controls and gas-valve will be turned off.
Sequences of events for operation:
1. Thermostat calls for heat.
2. The 24 volt relay is activated to turn on the exhaust blower.
3. The pressure switch proves that the exhaust blower is operating.
4. The temperature switches prove that temperatures are not in excess of their limits.
5. The ignition module is activated.
6. After 34 seconds of prepurge (exhaust blower running), the hot surface igniter (HSI) is activated.
7. After 34 seconds of heat up time for the HSI, the gas valve is opened.
8. The gas valve and HSI remains on for 4 seconds.
9. If flame is proven by the sensor, the gas valve remains open; if flame is not proven by the sensor the cycle
starts at step 5.
10. After three trials for ignition, the ignition module goes into lock-out.
11.
Power must be disconnected from the appliance in order to reset the ignition module.
MAINTENANCE
Periodically clean:
-The flue vent and screen.
-The condensate disposal pipe.
-Air intake Louvers.
-Burners.
To clean the burners, carefully remove each burner by removing the 2- #8 self drilling screws that hold the burner
to the burner bracket. Slide the burner forward off of the orifice. Use a rag or cotton swab to clean any debris that
is in the burner, burner ports, or carryover ports. Replace the burners by first sliding the venturi end (refer to figure
1 on page 6) over the orifice, and using the 2- #8 self drilling screws to attach the burner to the burner bracket
through the existing holes.
Annually inspect the HSI for any cracks or fractures.
The draft motor is permanently lubricated, and requires no maintenance. Annually inspect the high temperature
silicone tubing from the draft motor to the pressure switch to make sure there are no cracks and that the
connections are tight. REPLACE WITH HIGH 'TEMPERATURE HOSE RATED FOR 450°F AND INSIDE
DIAMETER 3/16" ONLY.
Do not pile snow in front of the louvered access panel. If excessive amounts of snow (1 foot or more) accumulate
in front of the appliance remove the snow so that the air openings and venting system are not obstructed.