State Water Heaters SUF 60120 THRU, Instruction Manual

Page: 53 / 80

53
PRIOR TO START UP
Installation and start up of this water heater requires abilities
and skills equivalent to that of a licensed tradesman in the field
involved, see
Qualifications
(page 6) .
DO NOT USE THIS APPLIANCE IF ANY PART HAS BEEN
EXPOSED TO FLOODING OR WATER DAMAGE . Immediately
call a qualified service agency to inspect the appliance and to
make a determination on what steps should be taken next. If the
unit is exposed to the following, do not operate heater until all
corrective steps have been made by a qualified service agency.
1. External fire
2. Damage
3. Firing without water
Light the water heater in accordance with the Lighting and
Operation Instruction label on the water heater and in this manual
Lighting the Water Heater
(page 54).
The water heaters covered by this manual are equipped with
an electronic control system, which automatically sequences
the Combustion Blower, pre and post purging of the combustion
chamber, the spark transformer, the 24-volt gas valve, Main
Burner ignition, and flame sensing. The control system will lock
out after three unsuccessful ignition attempts. See
Control System
Operation
(page 45).
START-UP PREPARATION
Before attempting start up, thoroughly study and familiarize
yourself with the exact
Sequence Of Operation
(page 57). Ensure
the water heater is properly grounded. Flame sensing requires an
adequate earth ground. If the water heater is not properly grounded
it will cause ignition failure.
Be certain that the water heater is full of water, that air is purged
from the gas and water lines and that there are no leaks in the gas
and water lines. Ensure all inlet water valves are open.
FILLING THE WATER HEATER
Follow these steps to fill the water heater prior to start up.
1. Close the heater drain valve.
2. Open a nearby hot water faucet to permit air in system to
escape.
3. Fully open the cold water inlet valve allowing the piping and
water heater to fill with water.
4. Close the hot water faucet opened in Step 2 as water starts
to flow.
INITIAL START UP
REQUIRED TEST EQUIPMENT
• One U-tube manometer, recommended ranges; 0-14”
W.C. (0-3.5 kPa) and 0-35” W.C. (0-8.7 kPa) or pressure
gauges.
• One digital manometer can be used in place of U-tube
manometers or pressure gauges. Recommended ranges;
-14.00 to +14.00” W.C. (0-3.5 kPa) resolution 0.01” W.C.
and 0-35” W.C. (0-8.7 kPa) resolution 0.10” W.C.
Note: All test equipment must be acclimated to ambient
temperature before calibration and use.
START-UP PROCEDURE
1. Using the control system menus, change the Operating Set
Point to the lowest temperature setting. See
Operating Set Point
and Differential Adjustment
(page 48).
2. Turn the water heater’s Enable/Disable switch to the "Disabled"
position.
3. Close the Main Gas Shut Off Valve, see
Figure 54
(page 40).
4. Wait five (5) minutes for any residual gas to clear.
5. Connect the manometer to the supply gas pressure port on the
gas valve. See
Figure 60
(page 53) and
Figure 61
(page 53) .
Note:
The manometer tubing should be purged before
taking any readings.
Water heaters covered by this manual have test ports for
supply and manifold gas pressure readings on the gas
valve. Using a small flat tip pocket screw driver - open
the needle valve inside the supply gas pressure test port
one full turn only; turn the needle valve screw counter-
clockwise to open the valve. Slide the manometer sensing
tube over the top of the test port. See
Figure 60
(page 53)
and
Figure 61
(page 53) .
6. Open the Main Gas Shutoff Valve.
7. Measure and record the supply gas pressure, this is a “static”
supply gas pressure reading; while the water heater is not firing.
Adjust supply gas pressure as necessary. See
Initial Start Up
(page 53) .
MANIFOLD GAS
PRESSURE
TEST PORT
( Non-Adjustable )
SUPPLY GAS
PRESSURE
TEST PORT
VENTURI
COMBUSTION
AIR INLET
GAS
VALVE
COMBUSTION
BLOWER
CONNECTION
Figure 60. Gas Valve/Venturi Assembly Top View
MANIFOLD GAS
PRESSURE
TEST PORT
( Non-Adjustable )
SUPPLY GAS
PRESSURE TEST PORT
Figure 61. Gas Valve Top Detail View
VENTURI
LOW GAS
PRESSURE
SWITCH
SUPPLY GAS
CONNECTION
GAS
VALVE
COMBUSTION
AIR INLET
Figure 62. Gas Valve/Venturi Assembly Side View
START UP