Carrier 48HJ20---28, 48PM16---28 manual To Shut Unit OFF Units with Thermostat Control, Fire Hazard

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TO LIGHT UNIT (UNITS WITH COMFORTLINK™ CONTROL)

(CONTINUED)

See Fig. 1 for location of gas valve. Refer to Fig. 3 while proceeding with the following steps.

Step 1 — Turn off the unit demand for cooling or heating by using the Scrolling Marquee. The Scrolling Marquee is located in the control box at the compressor end of the unit.

a. Push the ESCAPE key until a blank display screen is shown.

b.Push the DOWN arrow key until the SERVICE TEST LED is lit.

c. Push the

 

key. The display will show TEST.

ENTER

d. Push the

 

key again. The NO/YES display will

ENTER

flash.

 

e.Push the UP or DOWN key to toggle the display to

YES and then push ENTER . The unit will be locked off from heat, cooling or any operation. The controls will still function and the display will still operate.

NOTE: A password may be required to change Service Test values depending on previous settings configured in the unit. Default password is “1111.”

Step 2 — Close the external gas pipings manual shut off valve located outside the unit.

Step 3 — Turn off the electrical supply to the unit and install lockout tag.

Step 4 — Remove the heat section access panel.

Step 5 — Turn the Off/On selector switch on the gas valve to the OFF position and wait 5 minutes.

Step 6 — Move the Off/On selector switch on the gas valve to the ON position.

Step 7 — Replace the heat section access panel.

Step 8 — Remove lockout tag and turn on the electrical supply to unit.

NOTE: Normal operation will automatically begin. Service Test mode will automatically end (exit) after a recycle of power.

Step 9 — Open the external gas pipings manual shut off valve located outside the unit.

Step 10 — Using the Scrolling Marquee, enable the unit to run using the following procedure:

a. Push the ESCAPE key until a blank display screen is shown.

b.Push the DOWN key until the SERVICE TEST LED is lit.

c. Push the

 

key. The display will show TEST.

ENTER

d. Push the

 

key again. The NO/YES display will

ENTER

flash.

 

e.Push the UP or DOWN key to toggle the display to NO and then push ENTER . The unit will return to normal operation and exit SERVICE TEST mode.

Step 11 — To test the operation of the gas section, use the Scrolling Marquee test routine to energize the gas outputs and to turn on the gas.

Step 12 — For normal operation, make sure that the set points are at the normal heat set points.

!WARNING

FIRE, EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

If the main burners fail to light, or the blower fails to come on, shut down gas heating section and call your dealer for service.

TO SHUT UNIT OFF

(UNITS WITH THERMOSTAT CONTROL)

!WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Do not turn off the electrical power to unit without first turning off the gas supply. Should the gas supply fail to shut off or if overheating occurs, shut off gas valve to the unit before shutting off the electrical supply. Make sure to apply lockout tags.

See Fig. 1 for location of gas valve. Refer to Fig. 4 while proceeding with the following steps.

Step 1 — Set room thermostat to lowest temperature setting and set SYSTEM switch to OFF position.

Step 2 — Close the external gas pipings manual shut off valve located outside the unit.

Step 3 — Turn off the electrical power supply to the unit and install lockout tag.

Step 4 — Remove the heat section access panel. Step 5 — Turn the control dial on the main gas valve counterclockwise to the OFF position.

Step 6 — Replace the heat section access panel.

Step 7 — If unit is being shut down because of a malfunction, call your dealer as soon as possible.

If unit is being shut down because the heating season has ended, restore electrical power to the unit to ensure operation of the cooling system during the cooling season.

TO SHUT UNIT OFF

(UNITS WITH COMFORTLINK™

CONTROL)

!WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Do not turn off the electrical power to unit without first turning off the gas supply. Should the gas supply fail to shut off or if overheating occurs, shut off gas valve to the unit before shutting off the electrical supply. Make sure to apply lockout tags.

See Fig. 1 for location of gas valve. Refer to Fig. 5 while proceeding with the following steps.

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Contents Table of Contents Safety ConsiderationsTo Light Unit Units with Thermostat Control Post Unit Installation InspectionDetermine Type of Unit Control Electro-Mechanical ControlTo Light Unit Units with Comfortlink Control Typical Gas Heating SectionMain Step To Shut Unit OFF Units with Thermostat Control To Shut Unit OFF Units with Comfortlink ControlFire Hazard Main Maintaining Your Unit StepAir Filters Routine Maintenance and Care For the Equipment OwnerAlarm Status Units with ComfortLinkt Controls Integrated Gas Controller IGCRegular Dealer Maintenance Case of Trouble If insufficient heating or cooling is suspected

48HG14---28, 48HJ20---28, 48PG20---28, 48PM16---28 specifications

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