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Troubleshooting Guide
Start Up Conditions
THERMAL EXPANSION
Watcr supply systems max; bccat_sc of such events as high line
pressure, fi"c@cntcut-olin, the cffacctsol?wascr hammcr among
othcrs, havc inst',dled dcviccs such as presst_rc redudng valvcs,
check vdvcs, back flow prevcntcrs, ctc,,,m control these 9'pcs of"
problems, Whcn thcsc dc_4ccsarc not equipped with an intcrn'al
by+pass, and no other measures arc taken, the dc_4ccs cause the
_atcr _wstcmto bc dosed, As _atcr is heated, it expands (ther-
mal expansion) and closed _wstcmsdo not allow for dre cxpan-
sion of hcatcd _atcr,
The water within the waer hcaer yank _pands asit is heated and
increases the pressure of the vcatcrxTstcm. If the rcheving point of
the vcatcr heater's remperature_pressure relief valve is reached, the
v0vc will relieve the _ccss prcasure,The tenzperatuee-preasm_e
relief"valve is not intended for the comtant m.Jiefof thermal
_panslon. This is an unacceptable condition and must bc co>
retted,
It is recommended that any devices installed which could crcase a
closed svsrem have a by-pass and/or the s!_stcmhave an expan-
sion ta6k to relieve tl_c pressure built b_ thermal cxpanslon.
Thermal expansion tanks arc available f}om Sears stores and
through the Scars Service Canters. Contact the Ioca.1pltmtbing
inspector, water supplier and/or the Sears Service Center for
assistance in controlling these situations.
Thermal Expansion Tank Specifications
Modd Tank Capacity Dimensions in lnchcs Pipc Fitting
Ntmtbcr ln Gallons Diamctcr l.cngdl On Tank
153.33 ] 020 2 8 inchcs ]2_ inchc* _" Male
153.3371050 5 ]] inches ]4_inchc* _"Malc
HOT
WATER HEA_ER
COLD WATER
INLET FITTIhlC
HOT COLD
@
PRESSURE
REDUCING
VALVEWITH
BgPASS
(2)
PRESSUREGAUGE
WATER
SHUTOFF
RECOMMENDED INSTAIJ_A_ ON
(VERTICAL MOUNITING)
FLOOR,CEILING
jOISX,ETC.
STRAPPING
(3)
PRESSURE
REDUCING INLET COLD
VALVEWITH WA'_ER
BY-PASS SHUTOFF
Expansion Tank Sizing Chart
Expansion
Tank
Capadty
Nccdcd
Inlcd'
Watcr
Pressure
40psi
50psi
60psi
70psi
80psi
Watcr Hcatcr CapacagT,Gallons)
30 40 50 66 80
2 2 2 5 5
2 2 2 5 5
2 2 5 5 5
2 2 5 5 5
2 5 5 5 5
*Highast recorded inlct wascr pressure in a 24 hot_rpcriod or
regulated _atcr prcssure,
NOTE= Expansion tanks arc prc-chargcd with a 40 psi air
charge, If thc i,olct watcr prcssurc is highcr than 40 psi, thc
expansion tanks air pressurc must bc adjustcd to match that
pressure, but must not bc highcr than 80 psi.
@
PRESSUREGAUGE
AL_EPdhlATERECOMMENDED
INSTALLATION
(HORIZONTAL MouEn'ING)
STRANGE SOUNDS
Possiblc noiscs duc to cxpansion and contraction of somc mctal
parts during pcrio& of"hcat-up and cool-down do not represcnt
harmfialor dangerous conditions,
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