State Industries 197425-004 Temperature-Pressure Relief Valve Test, Draining and Flushing

Temperature-Pressure Relief Valve Test

DRAINING AND FLUSHING

DANGER

• Burn hazard.

• Hot water discharge.

• Keep clear of Temperature-

It is recommended that the water heater storage tank be drained and flushed every 6 months to reduce sediment buildup. The water heater should be drained if being shut down during freezing temperatures. See Typical Installation section in this manual for location of the water heater components described below.

Pressure Relief Valve

discharge outlet.

DANGER

• Burn hazard.

• Hot water discharge.

It is recommended that the Temperature-Pressure Relief Valve should be checked to ensure that it is in operating condition every 6 months.

When checking the Temperature-Pressure Relief Valve operation, make sure that (1) no one is in front of or around the outlet of the Temperature- Pressure Relief Valve discharge line, and (2) that water discharge will not cause any property damage, as water may be extremely hot. Use care when operating valve as the valve may be hot.

To check the relief valve, lift lever at the end of valve several times, see Figure 28. The valve should seat properly and operate freely.

If after manually operating the valve, it fails to completely reset and continues to release water, immediately close the cold water inlet to the water heater and drain the water heater, see Draining And Flushing on page 32. Replace the Temperature-Pressure Relief Valve with a properly rated/sized new one, see Temperature-Pressure Relief Valve on page 15 for instructions on replacement.

TEMPERATURE-PRESSURE

RELIEF VALVE

DISCHARGE PIPE

FIGURE 28.

If the Temperature-Pressure Relief Valve on the water heater weeps or discharges periodically, this may be due to thermal expansion.

Note: Excessive water pressure is the most common cause of Temperature-Pressure Relief Valve leakage. Excessive water system pressure is most often caused by “thermal expansion” in a “closed system.” See Closed Water Systems and Thermal Expansion on page 14-15. The Temperature-Pressure Relief Valve is not intended for the constant relief of thermal expansion.

Temperature-Pressure Relief Valve leakage due to pressure build up in a closed system that does not have a thermal expansion tank installed is not covered under the limited warranty. Thermal expansion tanks must be installed on all closed water systems.

DO NOT PLUG THE TEMPERATURE-PRESSURE RELIEF VALVE OPENING. THIS CAN CAUSE PROPERTY DAMAGE, SERIOUS INJURY OR DEATH.

Explosion Hazard

Temperature-Pressure Relief Valve must comply with ANSI Z21.22- CSA 4.4 and ASME code.

Properly sized Temperature-Pressure Relief Valve must be installed in opening provided.

Can result in overheating and excessive tank pressure.

Can cause serious injury or death.

• Keep hands clear of drain

valve discharge.

TO DRAIN THE WATER HEATER STORAGE TANK:

1.Turn off the electrical supply to the water heater.

2.Turn off the gas supply at the Main Gas Shutoff Valve if the water heater is going to be shut down for an extended period.

3.Ensure the cold water inlet valve is open.

4.Open a nearby hot water faucet and let the water run until the water is no longer hot.

5.Close the cold water inlet valve to the water heater.

6.Connect a hose to the water heater drain valve and terminate it to an adequate drain.

7.Open the water heater drain valve and allow all the water to drain from the storage tank.

8.Close the water heater drain valve when all water in the storage tank has drained.

9.Close the hot water faucet opened in Step 4.

10.If the water heater is going to be shut down for an extended period, the drain valve should be left open.

TO FLUSH THE WATER HEATER STORAGE TANK:

11.Turn off the electrical supply to the water heater.

12.Ensure the cold water inlet valve is open.

13.Open a nearby hot water faucet and let the water run until the water is no longer hot. Then close the hot water faucet.

14.Connect a hose to the drain valve and terminate it to an adequate drain.

15.Ensure the drain hose is secured before and during the entire flushing procedure. Flushing is performed with system water pressure applied to the water heater.

16.Open the water heater drain valve to flush the storage tank.

17.Flush the water heater storage tank to remove sediment and allow the water to flow until it runs clean.

18.Close the water heater drain valve when flushing is completed.

19.Remove the drain hose.

20.Fill the water heater - see Filling The Water Heater in this manual.

21.Turn on electrical supply to place water heater back in operation.

22.Allow the water heater to complete several heating cycles to ensure it is operating properly.

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