Operational Checklist - A.O. Smith BTI 120 Installation & Operation Manual

This checklist in conjunction with "TROUBLESHOOTING" and the "SEQUENCE OF OPERATION" should be used as an on-the-job
troubleshooting guide to identify the cause of incorrect system operation and suggest a remedy for its correction. Because
improper piping and wiring can result in unsatisfactory system performance, it is suggested that the installation be examined
before using the checklist. Be sure to refer to the correct piping and wiring diagram for the type of system that is installed.
The system should be filled with water, purged of air, valves properly set and utilities connected and ready to operate.
COMPLAINT
*Water not hot enough.
*Insufficient hot water
*See WATER TEMPERATURE
CONTROL WARNING (on
Page 5).
Water temperature too hot.
Heater makes sounds: sizzling. Condensation on outside
Rumbling.
Ticking or metallic sounds.
Pounding.
Combustion noises.
Water leaks.
Gas odors.

OPERATIONAL CHECKLIST

CAUSE
Thermostat set too low.
Thermostat out of calibration. Call serviceman
Thermostat set too low.
Thermostat out of calibration. Call serviceman.
Main manual gas shutoff
valve partially closed.
Heater too small for demand.
Thermostat differential is
too wide.
Heater recovery is slower.
Drafthood not installed or
one or more flue baffles.
Thermostat set too high.
of tank, normal.
Sediment accumulation on
bottom of tank.
Expansion and contraction-
normal.
Air chambers in piping have
become waterlogged.
Too much primary air.
Overfired heater; Incorrect
burners or orifice for type
of gas used.
Drain valve not closed
tightly.
If leakage source cannot
be corrected or identified,
call serviceman.
Heater is overfired.
Possible gas leaks.
USER
Set thermostat dial to a higher
temperature.
Set thermostat dial to a higher
temperature.
Open main manual gas shutoff
valve to fullest extent.
Space usage to give heater time
to restore water temperature.
Call serviceman.
Call serviceman.
Call serviceman.
Set thermostat to a lower setting.
Drain a quantity of water through
drain valve. If rumbling persists,
call a serviceman.
Drain piping system and refill.
Heater must be off while this is
being done.
Adjust shutters.
Call serviceman.
If drain valve cannot be closed
tightly, replace.
Shut off gas supply to heater
and close cold water inlet valve
to heater.
Shut off gas supply to heater
and call a serviceman.
Shut off gas supply to heater and
call gas company at once.
31
REMEDY
SERVICEMAN
Recalibrate thermostat. If thermostat cannot
be recalibrated, replace.
Recalibrate thermostat. If thermostat cannot
be recalibrated, replace.
Replace dual bulb controller if differential is
greater than 4°F.
Check gas input. If incorrect, adjust gas
pressure or replace main burner orifice.
Install drafthood or baffles as furnished
with unit.
Delime heater.
Check and correct as necessary.
Repair or in case of suspected tank leakage,
be certain to confirm before replacing heater.
Check for sooted flue passage.
Check for obstructed vent line.
Check backdraft or lack of draft.