AERCO KC1000 Heater 2002 - Manual (Page 38)

SAFETY DEVICE TESTING
5-2
HIGH GAS
PRESSURE
SWITCH
Figure 5.2
High Gas Pressure Switch
5.4 LOW WATER LEVEL FAULT TEST
1. Set the
ON/OFF switch in the OFF position.
2. Close the shut-off valves in the supply and
return piping to the unit.
3. Open the drain valve on the unit.
4. Allow air flow into the unit by either opening
the relief valve or by removing the 1/4” plug
in the top of the unit.
5. The LOW WATER LEVEL message will be
displayed and the
FAULT LED will flash after
the water level has gone below the level of
the probe.
6. Set the
ON/OFF switch to ON. The READY
light should remain off and the unit should
not start. If the unit does start, shut the unit
off immediately and refer fault to qualified
service personnel.
7. Close the drain and pressure relief valve or
reinstall the plug in the top of the unit if
removed.
8. Open the water shut-off valve in the return
piping to the unit to fill the shell.
9. Open the water shut-off valve in the supply
piping to the unit.
10. After the shell is full, press the
LOW
WATER L EVEL RESET button to reset the
low water cutoff. Press the
CLEAR button to
reset the
FAULT LED and clear the error
message.
11. Set the
ON/OFF switch to the ON position.
The unit is now ready for operation.
5.5 WATER TEMPERATURE FAULT
TEST
1. In the normal operating mode, allow the unit
to stabilize at its setpoint.
2. Lower the adjustable temperature limit
switch setting to match the outlet water tem-
perature. (See Fig. 5.3).
209
137
HARNESS
136
FROM SHELL
NC
NC
C NO
C
120
180
150
DIAL
TEMPERATURE LIMIT SWITCH
SETTING
Figure 5.3
Temperature Limit Switch Setting
3. Once the switch setting is approximately at
the actual water temperature, the unit should
shutdown. The
FAULT LED should be
flashing and the message HIGH WATER
TEMP SWITCH OPEN should be displayed.
The unit should not start.
4. Reset the temperature limit switch setting to
its prior setting.
5. The unit should start once the adjustable
temperature limit switch setting is above the
actual outlet water temperature.