GF
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128
Innovation Series Water Heaters
Chapter 3
OMM-0079_0B
USER MANUAL
Operation
Page
36
of
200
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
•
Ph.: 800-526-0288
07/21/11
3.8
START SEQUENCE
When the Control Box
ON/OFF
switch is set to the ON position, it checks all pre-purge safety switches to
ensure they are closed. These switches include:
•
Safety Shut-Off Valve Proof of Closure (POC) switch
•
Low Water Level switch
•
High Water Temperature switch
•
High Gas Pressure switch
•
Low Gas Pressure switch
•
Blower Proof switch
If all of the above switches are closed, the
READY
light above the
ON/OFF
switch will light and the unit
will be in the Standby mode.
When there is a demand for hot water, the following events will occur:
NOTE
If any of the Pre-Purge safety device switches are open, the appropriate fault message
will be displayed. Also, the appropriate messages will be displayed throughout the start
sequence, if the required conditions are not observed.
1. The
DEMAND
LED status indicator will light.
2. The unit checks to ensure that the Proof of Closure (POC) switch in the downstream Safety Shut-Off
Valve (SSOV) is closed. See Figure 3-3 for SSOV location.
Figure 3-3. SSOV Location
3. With all required safety device switches closed, a purge cycle will be initiated and the following events
will occur:
(a)
The Blower relay energizes and turns on blower.
(b)
The Air/Fuel Valve rotates to the full-open purge position and closes purge position switch. The
dial on the Air/Fuel Valve (Figure 3-4) will read 100 to indicate that it is full-open (100%).
(c)
The
VALVE POSITION
bargraph will show 100%.
