John Wood Commercial - AJWSC - Manual (Page 19)

Safety Shut-off
This water heater is designed to automatically shut-off in the
event of the following:
1. The pilot flame is extinguished for any reason.
2. The water temperature exceeds 96°C (205°F).
Read and understand these directions thoroughly before
attempting to operate the water heater (“Lighting &
Operating Instructions”). 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.
Checking the Draft
After successfully lighting the water heater, allow the unit to
operate for 15 minutes and check the drafthood relief open-
ing for proper draft. Pass a match flame around the relief
opening of the drafthood (See Figure 14). A steady flame
drawn into the opening indicates proper draft. If the flame
flutters or is blown out, combustion products are escaping
from the relief opening. If this occurs, do not operate the
water heater until proper adjustments or repairs are made to
the vent pipe system.
Water Temperature Regulation
The integrated control is adjusted to a temperature setting
of 49°C (120°F) when it is shipped from the factory. To make
a change to this setting, use the buttons on the front of the
integrated control to select the desired water temperature.
Important: Since most commercial installations utilize high-
er temperatures, the use of a tempering valve is strongly
recommended in all domestic hot water lines (i.e. public
restroom sinks, etc). Auxiliary commercial equipment (i.e.
dishwashers, laundry equipment, etc.) may require higher
temperature settings. Refer to instruction manuals supplied
with this type equipment for recommended temperature set-
tings.
Important: Adjusting the integrated control past the 49°C
(120°F) setting will increase the risk of scald injury.
Water Heater Operation
When the integrated control calls for heat, it will signal the
damper to open. Once the damper fully opens, it will signal
the igniter to light the pilot. The pilot will then ignite the main
burners. 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 22 for a sequence of
operation flowchart.
V) OPERATION
WARNING:
Risk of scalding
Hot water can produce third degree burns
in 6 seconds at . . . . . . . .60°C (140°F)
in 30 seconds at . . . . . . .54°C (130°F)
in 5 minutes at . . . . . . . . .49°C (120°F)
Water temperature over 52°C (125°F) can cause
severe burns instantly or death from scalds.
Children, disabled and elderly are at highest risk of
being scalded.
Feel water before bathing or showering.
Temperature limiting valves are recommended.
– 19 –
DANGER
Burn Hazard
Do not touch vent.
Doing so can result in
burns.
Figure 14 Vent Draft Test