John Wood Commercial - AJWS - Manual (Page 17)

INSTALLATION CHECKLIST
Water Heater Location Requirements
• Centrally located with the water piping system. Located
as close to the gas piping and vent pipe system as pos-
sible.
• Located indoors and in a vertical position. Protected from
freezing temperatures.
• Proper clearances from combustible surfaces maintained
and not installed directly on a carpeted floor. Sufficient
room to service the water heater.
• Provisions made to protect the area from water damage.
Properly sized drain pan installed and piped to an ade-
quate drain.
• Installation area free of corrosive elements and flamma-
ble materials.
Vent Pipe System
• Drafthood and damper properly installed.
• Vent connectors securely fastened with screws and sup-
ported properly to maintain 152mm (6 in) clearance.
• Vent pipe and fittings of approved material.
• Acceptable size, length, and number of elbows on
exhaust outlet pipe.
• Installed in accordance with prevailing provisions of local
codes, or in the absence of such, National Fuel Gas
Code, NFPA 54, ANSI Z223.1-Latest Edition. Canadian
Installations must be performed in accordance with
CAN/CSA-B149.1.
• Drafthood or vent pipe should not be obstructed in any
way.
Vent Termination
Vertical
• Vertical gas vents must terminate with a listed cap or
other roof assembly and be installed according to their
manufacturer’s instructions.
Water System Piping
• Temperature and pressure relief valve properly installed
with a discharge line run to an open drain and protected
from freezing.
• All piping properly installed and free of leaks.
• Water heater completely filled with water.
• A properly sized expansion tank must be installed on all
closed systems.
• A tempering valve should be installed per the manufac-
turer’s instructions.
Gas Supply and Piping
• If using a flexible gas connector, make sure its rating tag
matches or exceeds the input of the water heater.
• Adequate pipe size and of approved material.
• Gas supply is the same type as listed on the water heater
data plate.
• Gas line equipped with full opening shut-off valve, union
and drip leg.
• Approved pipe joint compound used.
• Chloride-free soap and water solution or other approved
means used to check all connections and fittings for pos-
sible gas leaks.
Electrical Connections
• Unit must be “hard-wired” to a dedicated 120V power
supply.
• Proper polarity.
• Water heater properly grounded.
• Installed in accordance with prevailing provisions of local
codes, or in the absence of such, National Electrical
Code, ANSI/NFPA 70 and/or the CSA C22.1, Electrical
Code.
OPERATING YOUR WATER HEATER
Read and understand these directions thoroughly before
attempting to operate the water heater (see Lighting
Instructions on page 20). Check the data plate on the front
of the water heater for the correct gas. Do not use this water
heater with any gas other than the one listed on the data
plate. If you have any questions or doubts, consult your gas
supplier or gas utility company.
L.P. (Propane) Models
Propane gas is heavier than air and in the occurrence of a
leak in the system, the gas will settle on the floor level.
Basements, crawl spaces, skirted areas under mobile
homes (even when ventilated), closets and areas below
ground level will serve as pockets for the accumulation of
gas. Before lighting a propane gas water heater, smell all
around the appliance at floor level. If you smell gas, follow
the instructions as given in the warning on the front page.
When your propane tank runs out of fuel, turn off the gas at
all gas appliances including pilot lights. After the tank is
refilled, all appliances must be re-lit according to their man-
ufacturer’s instructions.
Water Heater Operation
When the thermostat calls for heat, it will signal the damper
to open. Once the damper fully opens, it will signal the ignit-
er to light the pilot. The pilot will then ignite the main burn-
ers. The water heater will operate until the call for heat
ends. At this time the main burners and pilot will shut-off and
the damper will close. See Figure 12 for a sequence of
operation flowchart.
17
Figure 12: Sequence of Operation
ELECTRICAL POWER
APPLIED TO UNIT
THERMOSTAT CALLS
FOR HEAT
DAMPER OPENS
PILOT IGNITES
PILOT IGNITES
BURNER
WATER HEATER
OPERATES TILL
CALL FOR HEATING
ENDS.
THERMOSTAT
SATISFIES
BURNER & PILOT
SHUT OFF
DAMPER CLOSES