Harman® • PF-120 Installation Manual_R1 • 2014 -___ • 03/1426
3-90-08121i
H. Installing Electrical Power
Toinstallpowertothefurnacerstremovethecoveronthe
circuitbreakerjunctionbox.Figure5.18.
Insideyouwillndthemainterminalblock.ReferenceSection
6,ItemB“WiringDiagram”ofthismanualforlocationofmain
terminalblockandproperpowerconnections.Inthebottom
oftheboxaknockoutholeisprovidedfortheincomingwire
andbulkhopperrelay.
Theminimum recommendedcircuitis15Amp120VAC,60
Hz.Thisfurnaceshouldbetheonlyapplianceonthecircuit.
This furnace should never be powered by the use of an
extension cord.
Therecommendedhighandlowvoltagesare,130VAC,60
Hz maximum high voltage, and 113 VAC, 60 Hz minimum
lowvoltage.
Thefurnacewillcontinuetooperateatvoltagesaslowas105
VAC,althoughitcannotbeguaranteedthatautomaticignition
willoccur.Also,thereisthepossibilityofadistributionblower
motoroverload.
NOTE: If other sources of electrical power are to be
used (such as a generator) for normal operation or
emergency operation, this source should be checked
before installation. Many generators and inverters may not
supply 120 VAC. 60Hz. power stable enough to operate
the control board properly. (Control board damage could
occur).
Checking & Recording the Low Draft:
Aftertheventingiscompleted,thereboxlowdraftwillneedto
becheckedandpossiblyadjusted.Afterremovingthe3/8”bolt
fromthedraftholeshowninFigure5.19,insertthedraftmeter
tube.Theinnerashdoorandthehopperlidmustbelatched
duringthistest.(Itisrecommendedthatthedraftmeterhave
ascaleof0to1”WC.)
TurntheFeedAdjusterto“Test”.thiswillstartthecombustion
blower and allow you to check and record the High Draft
______-IWCdate_______(Thereisnoadjustmentforthe
HighDraft)
After the first 60 seconds, the “Test” mode lowers the
combustionblowervoltagetotheLowBurnvoltage.During
this lowered voltage cycle the low burn draft must be
checked andadjustedifnecessary.Therecommendedlow
draftsettingshouldbebetween-.45&-.55IWC.Depending
ontheamountofverticalrise,itmaynotbepossibletogeta
lowdraftreadinginthisrange.Inthiscase,amaximumlow
draftof-.55isacceptable.
Theadjustmentscrewisthroughthesmallholetotheright
of the Igniter Light. Figure 5.20.Adjusted the Low Draft to
__________-IWC.
Don’t forget to turn off of “Test” mode.
Figure 5.18
Draftmeterbolt
FurnaceControlCover
Figure 5.19
“Test”
LowDraftAdjustmentPot
Figure 5.20
CircuitBreakerJunctionBox