Pomona, CA Clemmons, NC Nashville, TN
Tel: 908-355-7995 www.hayward-pool.com
USE ONLY HAYWARD GENUINE REPLACEMENT PARTS
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To remove/replace the ignition control board:
1. Turn pump, gas supply, and heater power OFF.
2. Remove the front access panel.
3.
Disconnect all wires from the printed circuit board.
4.
Detach the board from the sheet metal panel by compressing the plastic standoffs.
5.
Replace the board, and reverse the above steps to reassemble.
To remove/replace the display board or keypad:
1. Turn pump, gas supply, and heater power OFF.
2. Remove the front access panel.
3.
Remove the 4 screws and remove the plastic bezel & keypad assembly from the sheet metal panel
on the front of the heater.
4.
The display board is attached to the back side of the bezel & keypad assembly.
5.
Detach the board from the plastic bezel by removing the small screws and removing the board
from the (4) spring clips near the center of the board.
6.
Replace the display board or bezel & keypad assembly, and reverse the above steps to reassemble.
BLOWER VACUUM SWITCH:
The blower vacuum switch is a safety device that prevents the ignition sequence from continuing unless
the blower is developin
g suf
fi
cient air
fl
ow for combustion. Figure 15 shows the location of the blower vacu-
um switch in the heater cabinet. When the blower achieves suf
fi
cient air
fl
ow, the negative pressure created in
the blower housing closes the contacts on the blower vacuum switch, indicating to the ignition control board
that it is safe to continue the ignition sequence. A silicone tube connects the blower vacuum switch with the
blower.
To remove the blower vacuum switch:
1. Turn pump, gas supply, and heater power OFF.
2. Remove the front access panel.
3. Remove the wires from the vacuum switch.
4. Pull the tubing from the hose barb on the switch.
5. Remove the (2) screws that secure the pressure switch to the control panel.
6. Reverse the above procedure to install the blower vacuum switch.
HIGH LIMIT SWITCHES:
The high limit is an automatically resetting safety device wired in series with the thermostat and gas
valve. S
ee Figure 18. T
he heater is equipped with two automatic high limits, located on the water header.
If the water temperature exceeds the limit set point, the gas valve will be closed, shutting off gas supply to
the burners.
Erratic high limit operation is often an indication of a problem with water
fl
ow. Reduced
fl
ow may be caused by:
1. Clogged
fi
lter or strainer.
2. Excessive
fl
ow through the external bypass if one is used.
3. Lime scale accumulation in the heat exchanger.