Reliance Water Heaters HE50 76N Series 100 用户手册

16

As water is heated, it expands (thermal expansion). In a closed system

the volume of water will grow when it is heated. As the volume of water 

grows there will be a corresponding increase in water pressure due 

to thermal expansion. Thermal expansion can cause premature tank 

failure (leakage). This type of failure is not covered under the limited

warranty. Thermal expansion can also cause intermittent Temperature-

Pressure Relief Valve operation: water discharged from valve due to 

excessive pressure build up. This condition is not covered under the 

limited warranty. The Temperature-Pressure Relief Valve is not intended 

for constant relief of thermal expansion.
A properly sized thermal expansion tank must be installed on all closed 

systems to control the harmful effects of thermal expansion. Contact a local 

plumbing service agency to have a thermal expansion tank installed.
note: to protect against untimely corrosion of hot and cold 

to copper pipe.
All gas piping must comply with local codes and ordinances or with 

the National Fuel Gas Code (ANSI Z223.1/ NFPA-54) or the Natural

Gas and Propane Installation Code (CAN/CSA B149.1) whichever

applies. Copper and brass tubing and fittings (except tin lined copper

tubing) should not be used.

Figure 10 shows typical attachment of water piping to the water heater. 

The water heater is equipped with 3/4 inch NPT water connections.
note: If using copper tubing, solder tubing to an adapter before 

It will harm the dip tube and damage the tank.
T & P Valve and Pipe Insulation (if supplied)
Remove insulation for T & P valve and pipe connections from carton.

Fit pipe insulation over the incoming cold water line and the hot water 

line. Make sure that the insulation is against the top cover of the heater.

Fit T & P valve insulation over valve. Make sure that the insulation 

does not interfere with the lever of the T & P valve.
Secure all insulation using tape.

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.

This water heater is provided with a properly rated/sized and certified

combination Temperature-Pressure Relief Valve (T&P valve) by the

manufacturer. The valve is certified by a nationally recognized testing

laboratory that maintains periodic inspection of production of listed 

equipment of materials as meeting the requirements for Relief Valves 

for Hot Water Supply Systems, ANSI Z21.22 • CSA 4.4, and the code

requirements of ASME.
If replaced, the new T&P valve must meet the requirements of local 

codes, but not less than a combination Temperature-Pressure Relief 

Valve rated/sized and certified as indicated in the above paragraph.

The new valve must be marked with a maximum set pressure not to 

exceed the marked hydrostatic working pressure of the water heater 

(150 psi = 1,035 kPa) and a discharge capacity not less than the

water heater Btu/hr or kW input rate as shown on the water heater’s

model rating plate.
Note: In addition to the factory installed Temperature-Pressure Relief 

Valve on the water heater, each remote storage tank that may be installed 

and piped to a water heating appliance must also have its own properly 

sized, rated and approved Temperature-Pressure Relief Valve installed. 

Call the toll free technical support phone number listed on the back cover 

of this manual for technical assistance in sizing a Temperature-Pressure 

Relief Valve for remote storage tanks.

For safe operation of the water heater, the Temperature-Pressure 

Relief Valve must not be removed from its designated opening nor 

plugged. The Temperature-Pressure Relief Valve must be installed 

directly into the fitting of the water heater designed for the relief

valve. Install discharge piping so that any discharge will exit the 

pipe  within  6  inches  (15.2  cm)  above  an  adequate  floor  drain,

or external to the building. In cold climates it is recommended 

that it be terminated at an adequate drain inside the building. Be 

certain that no contact is made with any live electrical part. The