Maintenance And Service; Unit Draining And Filter Cleaning - A.O. Smith T-H3M-DV Installation Manual And Owner's Manual

On-demand water heater

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Table Of Contents

Table of Contents

Turn off the electrical power supply and close the manual gas shutoff valve

and the manual water control valve before servicing

WARNING

• Clean the cold-water inlet filter (Refer to the Unit Draining and Filter Cleaning Section on this page)

• Be sure that all openings for combustion and ventilation air are not blocked

• The venting system should be checked annually for any leaks, corrosion, blockages or damage

• The burner should be checked annually for dust, lint, grease or dirt

• Keep the area around the water heater clear Remove any combustible materials, gasoline or any

flammable vapors and liquids

• In accordance with all local codes and common safety practices, water discharged from the pressure

relief valve can cause severe burns instantly from scalding DO NOT touch the pressure relief valve

• If the relief valve discharges periodically, it may be due to thermal expansion in a closed water supply

system Contact the water supplier or local plumbing inspector on how to correct this situation

• Visual check of burner flames (see below) through the burner window in the burner assembly located

at the middle of the water heater

The manufacturer recommends having the water heater checked once a year or as necessary by a licensed

technician If repairs are needed, any repairs should be done by a licensed technician

Blue flame

Satisfactory

UNIT DRAINING AND FILTER CLEANING

1. Close the manual gas shutoff valve

2. Turn off power to the water heater and wait a couple of

seconds Turn on again

3. Wait 30 seconds, and then turn off power to the water

heater, yet again

4. Close the water shutoff valve

5. Open all hot water taps in the house When the residual

water flow has ceased, close all hot water taps

6. Have a bucket or pan to catch the water from the water

heater's drain plugs Unscrew the Small drain plug first

and unscrew the Large drain plug next to drain all the

water out of the water heater

7. Wait a few minutes to ensure all water has completely

drained from the water heater

8. Clean the filter: Check the water filter located within the

cold inlet With a tiny brush, clean the water filter of any

debris which may have accumulated and reinsert the filter

back into the cold water inlet

9. Securely screw the drain plugs back into place

Hand- tighten only