A.O. Smith DIRECT VENTED GAS MODELS Installation And Operating Manual page 43

PROBLEM
INSUFFICIENT HOT
WATER
SLOW HOT WATER
RECOVERY
DRIP FROM RELIEF
VALVE
THERMOSTAT FAILS TO
SHUT OFF
COMBUSTION ODO RS
SMOKING AND CARBON
FORMATION (SOOTING)
CONDENSATION
BURNER FLAME
FLOATS AND LIFTS OFF
PORTS
BURNER FLAME TOO
HIGH
FLAME BURNS AT
ORIFICE
POSSIBLE CAUSE(S)
1. Thermostat set too low
2. Sediment or lime in tank
3. Water heater too small
4. Wrong piping connections
5. Leaking faucets
6. Wasted hot water
7. Long runs of exposed piping
8. Hot water piping in outside wall
9. Low gas pressure
10. Leaks or cracks in dip tube
11. Incorrect plumbing/plumbing crossover
1. Insufficient combustion air
2. Venting/flue clogged
3. Low gas pressure
4. Improper calibration
5. Gas control/thermostat set too low
6. Water heater too small
7. Wrong piping connections
8. Wasted hot water
9. Sediment or lime in tank
1. Excessive water pressure
2. Heater stacking
3. Closed water system/thermal
expansion
1. Defective gas control/thermostat
2. Improper calibration
1. Insufficient ventilation air
2. Flue clogged or vent system blocked
3. Heater installed in a confined area
1. Insufficient combustion air
2. Low gas pressure
3. Venting/flue clogged
4. Defective gas control/thermostat
5. Burner flame yellow-lazy
1. Temperature setting too low
2. Water heater too small
1. Orifice too large
2. High gas pressure
3. Flue clogged
1. Orifice too large
2. High gas pressure
1. Defective gas control/thermostat
2. Low gas pressure
3. Orifice not properly installed
www. hotwater .com
CORRECTION
1. Turn temperature dial to desired setting
2. Drain/flush-provide water treatment if
needed
3. Install adequate size heater
4. Correct piping-dip tube must be in cold
inlet
5. Repair faucets
6. Advise customer
7. Insulate piping
8. Insulate piping
9. Check with gas utility company
10. Check dip tube. Replace if faulty
11. Correct cold water crossover
1. Check vent termination hood and
venting, flueway, flue baffle and burner
2. Clean flue, locate source and correct
3. Check with gas utility company
4. Replace gas control/thermostat
5. Turn temperature dial to desired
setting
6. Install adequate size heater
7. Correct piping-dip tube must be in
cold inlet
8. Advise customer
9. Drain/flush - provide water treatment if
needed
1. Use a pressure reducing valve and
relief valve
2. Lower the thermostat setting
3. See "Closed System/Thermal
Expansion"
1. Replace gas control/thermostat
2. Replace gas control/thermostat
1. Provide ventilation to the water heater.
Check flueway, flue baffle, burner
2. Clean, locate source and correct
3. Provide fresh air ventilation
1. Check vent termination hood and
venting, flueway, flue baffle and burner
2. Check with gas utility company
3. Clean, locate source and correct
4. Replace gas control/thermostat
5. See "Burner Flame Yellow-Lazy"
1. Increase the temperature setting
2. Install adequate size heater
1. Replace with correct orifice
2. Check with gas utility company
3. Clean flue and burner-locate source
and correct
1. Replace with correct orifice
2. Check with gas utility company
1. Replace gas control/thermostat
2. Check with gas utility company
3. Reinstall the orifice
43