RESIDENTIAL GAS AND ELECTRIC WATER HEATER
SERVICE HANDBOOK Important Service Reminder
Any time service is performed on C3 TECHNOLOGY product the Five Point Inner Door Seal Inspection
outlined in the Sealed Combustion Chamber section should be performed and the LDO Screen (s) should
be inspected for proper installation (arrows up) and cleaned before leaving.
Other features
All C3 TECHNOLOGY models will feature Green Choice by having a low NOx (nitrous oxide) burner which
meets SCAQMD rule 1121. All C3 TECHNOLOGY models will have a brass drain valve standard.
See the “Technical Bulletins Section” of this manual for explanations of:
Water Hammer
Mineral Buildup
Aluminum Hydroxide
Condensation
Discolored Water
Smelly Water
Chlorination Process
Lack of hot water
Thermal Expansion
Temperature and Pressure Relief Valve Operation
Parts Replacement – The parts on these models may change due to improvements/changes in
the products. To order the current, correct replacement part for your model gas water heater, you
must know the model number and (complete) serial number of your water heater. This
information will be located on a black and white label, on the front of your water heater – this label
will also display a star within a circle (the CSA symbol). A sample might be:
Model “PCVG-50 – 250” “Ser No. MB03-(numbers) – 250”.
To order parts, contact your local A.O. Smith Contractor or Distributor, phone AOS
parts at 800-433-2545 or contact A. O. Smith on Web site:
“www.aosmithwaterheaters.com”
A.O. Smith Water Products Company Technical Training Department
©2005 Ashland City, TN
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