WT8840 & WT8860 TRADE WATER HEATER CONTROLS
WARNING
Fire or Explosion Hazard.
Can cause severe injury, death or property
damage.
Follow these warnings exactly:
1.To avoid dangerous accumulation of fuel
gas, turn off gas supply at the appliance
service valve before starting installation
and perform the Gas Leak Test after
completion of installation.
2. Always install a sediment trap in gas
supply line to prevent contamination of
ignition system control.
3.Follow the appliance manufacturer
instructions if available; otherwise, use
these instructions as a guide.
WARNING
Scalding Hazard.
Can cause burns, severe injury or death.
Always use a direct replacement sensor
assembly when replacing a temperature
sensor.
Location
The WT88xx controls are mounted on the outside of
the water heater tank. See Fig. 2.
WT8840
Fig. 2. Mounting the WT88xx controls on the
water heater tank.
Install Control to Water Tank
1. To install the water heater control to the water
tank, drain the tank first, and then screw the
assembly into the spud until the bracket is
square. Use a maximum torque of 31 ft.-lbs. plus
one turn.
2. Follow steps in the Connect Gas Supply section.
IMPORTANT
These water heater system controls are
shipped with protection for the inlet and outlet
tappings. Do not remove the protection until
you are ready to connect the piping.
Connect Gas Supply
All piping must comply with local codes and
ordinances or with the National Fuel Gas Code (ANSI
Z223.1 NFPA No. 54), whichever applies. Tubing
installation must comply with approved standards
and practices.
34-00013EF—05
MOUNTING
WELL ASSEMBLY
ACCESS TO TANK
M36123B
1. Use a new, properly reamed pipe free from chips.
If tubing is used, make sure the ends are square,
deburred and clean. All tubing bends must be
smooth and without deformation.
2. Ensure that gas supply is turned off.
3. Run pipe or tubing to the water heater control. If
tubing is used, obtain a tube-to-pipe coupling to
connect the tubing to the control.
4. Install a sediment trap in the supply line to the
water heater control. See Fig. 3.
PIPED
DROP
GAS
SUPPLY
HORIZONTAL
3 IN.
(76 MM)
MINIMUM
DROP
TUBING
GAS
HORIZONTAL
SUPPLY
1
RISER
3 IN.
(76 MM)
MINIMUM
WARNING
EXPLOSION HAZARD.
FAILURE TO FOLLOW PRECAUTIONS CAN
RESULT IN A GAS-FILLED WORK AREA.
SHUT OFF THE MAIN GAS SUPPLY BEFORE REMOVING END CAP.
TEST FOR GAS LEAKAGE WHEN INSTALLATION IS COMPLETE.
1
ALL BENDS IN METALLIC TUBING SHOULD BE SMOOTH.
Fig. 3. Install a sediment trap in the supply line.
WARNING
Explosion Hazard.
Can cause severe injury, death or property
damage.
Check for gas leaks with soap and water
solution any time work is done on a gas system.
5. Apply a moderate amount of good quality pipe
compound, leave two end threads bare. Do not
use pipe dope on the outlet. See Fig. 4
6. Remove the seals over the water heater control
inlet and outlet.
7. Connect the pipe to the water heater control inlet
and outlet. Use a wrench on the square end of
the water heater control. Maximum torque on
the inlet is 40 ft-lbs.; maximum torque on the
outlet is 30 ft-lbs.
8. Position compression fitting in pilot outlet and
engage threads. See Fig. 5 for controls and
connections. Turn until finger tight, then tighten
one more turn with a wrench. Do not overtighten.
4
M29522B