CHAPTER 6
SAFETY DEVICE TESTING
PR1: 10/18//12 AERCO International Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
•
Ph: 800-526-0288
Page 71 of 166
GF-120
OMM-0041 0E
Benchmark 1.5LN Low NOx Boiler
Installation, Operation and Maintenance Manual
The unit should shut down and display a
HIGH GAS PRESSURE
fault message when
6.
the gas pressure exceeds 4.7” W.C. The
FAULT
indicator should also start flashing.
Reduce the gas pressure back to 3.0” W.C.
7.
Press the
CLEAR
button on the Control Box to clear the fault.
8.
The fault message should clear and the
FAULT
indicator should go off. The unit should
9.
restart.
Upon test completion, close the ball valve and remove the manometer. Replace the
10.
1/4“ plug removed in step 1.
6.4 LOW WATER LEVEL FAULT TEST
To simulate a low water level fault:
Set the
ON/OFF
switch to the
OFF
position
1.
Close the water shut-off valves in the supply and return piping to the unit.
2.
Slowly open the drain valve on the rear of the unit. If necessary the unit’s relief valve
3.
may be opened to aid in draining.
Continue draining the unit until a
LOW WATER LEVEL
fault message is displayed and
4.
the
FAULT
indicator flashes.
Place the unit in the Manual Mode and raise the valve position above 30%.
5.
Set the
ON/OFF
switch to the
ON
position. The
READY
light should remain off and the
6.
unit should not start. If the unit does start, shut the unit off immediately and refer fault to
qualified service personnel.
Close the drain and pressure relief valve used in draining the unit.
7.
Open the water shut-off valve in the return piping to the unit.
8.
Open the water supply shut-off valve to the unit to refill.
9.
After the shell is full, press the
LOW WATER LEVEL RESET
button to reset the low
10.
water cutoff.
Press the
CLEAR
button to reset the
FAULT
LED and clear the displayed error
11.
message.
Set the
ON/OFF
switch to the
ON
position. The unit is now ready for operation.
12.
6.5 WATER TEMPERATURE FAULT TEST
A high water temperature fault is simulated by adjusting the automatic over-temperature switch.
This switch is accessible from the front of the unit as shown in Figure 6-2.
Start the unit in the normal operating mode. Allow the unit to stabilize at its setpoint.
1.
Lower the adjustable over-temperature switch setting to match the displayed OUTLET
2.
TEMPERATURE.
Once the adjustable over-temperature switch setting is approximately at, or just below,
3.
the actual outlet water temperature, the unit should shut down. The
FAULT
indicator
should start flashing and a
HIGH WATER TEMP SWITCH OPEN
fault
message should
be displayed. It should not be possible to restart the unit.
