Pressure Switch Removal/Replacement - A.O. Smith GPVL-50 Service Handbook

PRESSURE SWITCH REMOVAL/REPLACEMENT

PRESSURE SWITCH
Important: Use only factory authorized replacement parts.
If you lack the necessary skills to properly perform the
installation, you should not proceed, but get help from a
qualifi ed service technician.
Tools required:
•
Phillips Head Screwdriver
•
Ratchet with 1/4" socket or 1/4" nutdriver
Removing Pressure Switch
1. Set the gas control valve/thermostat to its lowest
setting by turning the knob counter-clockwise to the
VAC point (see Figure 3).
2. Turn gas control switch to the "OFF" position and turn
"OFF" the gas supply to the unit (see Figure 3).
3. Disconnect the electrical power to the water heater
from the wall outlet.
4. Use a 1/4" nutdriver or 1/4" socket & ratchet to loosen
the screw on the junction box. Remove and retain the
screw and junction box cover (see Figure 30).
5. Remove the air pressure tubing from the air pressure
switch by pulling upward on the tubing at the
connection to the air pressure switch.
6. After noting the position of each electrical fl ag terminals,
remove the two (2) electrical fl ag terminals from the
switch by pulling outward and off the switch.
7. Using a hex head screwdriver, remove and retain the
2 screws securing the bracket to the junction box (see
Figure 30).
8. Using a hex head screwdriver, remove and retain the
2 screws securing the pressure switch to the bracket
(see Figure 30).
26
Installing Pressure Switch
1. Using a hex head screwdriver, secure the new pressure
switch to the bracket with the screws removed in step
8 above. Care should be taken to ensure the proper
orientation of the bracket and pressure switch (see
Figure 30).
2. Using a hex head hex screwdriver, secure the bracket
to the junction box with the screws removed in step 7
above (see Figure 30).
3. Reattach the two (2) electrical flag terminals by
pushing the flag terminals onto the switch. Care
MUST be taken to ensure that each of the electrical
fl ag terminals is in its original position.
4. Reattach the air pressure tubing to the air pressure
switch by pushing the tubing onto the connector until
the end of the tubing reaches the shoulder of the
connector.
5. Replace the blower's junction box door by reusing the
screw removed in step 4 above.
6. Reconnect the electrical power to the water heater in
the wall outlet and turn the gas supply back "ON" to
the gas control valve/thermostat.
7. Restart the water heater by following the directions on
the "Lighting and Operating Instructions" label located
on the front of the water heater.
PRESSURE
TUBING
JUNCTION
JUNCTION
BOX
BOX
AIR
COVER
PRESSURE
SWITCH
BRACKET
SCREWS
SCREW
Figure 30
AIR