American Water Heater American Water Heaters Residential Gas Water Heater Water Heater User Manual


 
15
THERMAL EXPANSION
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 water
ttings, it is strongly recommended that di-electric unions or couplings
be installed on this water heater when connected 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).Copperandbrasstubing
andttings(excepttinlinedcoppertubing)shouldnotbeused.
FIGURE 10.
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
attaching the adapter to the water heater connections. Do not solder
the water lines directly to the water heater connections. It will harm
the dip tube and damage the tank.
T & P Valve and Pipe Insulation
1. Locate the temperature and pressure relief valve on the water heater
(alsoknownasaT&Preliefvalve).SeeFigure11.
2. Locate the slit running the length of the T&P relief valve insulation.
3.SpreadtheslitopenandttheinsulationovertheT&Preliefvalve.See
Figure 11. Apply gentle pressure to the insulation to ensure that it is fully
seated on the T&P Relief Valve. Once seated, secure the insulation with
duct tape, electrical tape, or equivalent. IMPORTANT: The insulation
and tape must not block the discharge opening or hinder access to the
manualrelieflever(Figure11).Ensureadischargepipeisinstalledinto
the T&P valve discharge opening per the instructions in this manual.
4.Locatethehotwater(outlet)&coldwater(inlet)pipestothewaterheater.
5. Locate the slit running the length of a section of pipe insulation.
6.Spreadtheslitopenandsliptheinsulationoverthecoldwater(inlet)
pipe. Apply gentle pressure along the length of the insulation to ensure
that it is fully seated around the pipe. Also, ensure that the base of
theinsulationisushwiththewaterheater.Onceseated,securethe
insulation with duct tape, electrical tape, or equivalent.
7.Repeatsteps5and6forthehotwater(outlet)pipe.
8. Add additional sections of pipe insulation as needed.
FIGURE 11.
TEMPERATURE-PRESSURE RELIEF VALVE
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.
Thiswaterheaterisprovidedwithaproperlyrated/sizedandcertied
combinationTemperature-PressureReliefValve(T&Pvalve)bythe
manufacturer.Thevalveiscertied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certied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tting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oor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