Carrier 58CTA/CTX Check Safety Controls, Checklist, Stage Furnace Blower OFF delay Setup Switch

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Table 14 – 2-Stage Furnace Blower OFF delay Setup Switch

DESIRED HEATING MODE

SETUP SWITCH

SETUP SWITCH

BLOWER OFF DELAY (SEC.)

SW---2

SW---3

90

OFF

OFF

120

OFF

ON

150

ON

OFF

180

ON

ON

58CT

THERMOSTAT SUBBASE TERMINALS WITH THERMOSTAT REMOVED (ANITICIPATOR, CLOCK, ETC.,

MUST BE OUT OF CIRCUIT.)

HOOK-AROUND AMMETER

R Y W G

10 TURNS

FROM UNIT 24-V

CONTROL TERMINALS

EXAMPLE:

5.0 AMPS ON AMMETER

=

0.5 AMPS FOR THERMOSTAT

10 TURNS AROUND JAWS

ANTICIPATOR SETTING

 

 

A96316

Fig. 55 - Amp. Draw Check with Ammeter

Step 4 — Check Safety Controls

The flame sensor, gas valve, and pressure switch were all checked in the Start-up procedure section as part of normal operation.

1.Check Main Limit Switch(es)

This control shuts off combustion system and energizes air-circulating blower motor, if furnace overheats. By us- ing this method to check limit control, it can be established that limit is functioning properly and will operate if there is a restricted return-air supply or motor failure. If limit control does not function during this test, cause must be determined and corrected.

a.Run furnace for at least 5 minutes.

b.Gradually block off return air with a piece of cardboard or sheet metal until the limit trips.

c.Unblock return air to permit normal circulation.

d.Burners will re-light when furnace cools down.

2.Check draft safeguard switch.

The purpose of this control is to cause the safe shutdown of the furnace during certain blocked vent conditions.

a.Verify vent pipe is cool to the touch.

b.Disconnect power to furnace and remove vent connector from furnace vent elbow.

c.Restore power to furnace and set room thermostat above room temperature.

d.After normal start-up, allow furnace to operate for 2 minutes, then block vent elbow in furnace 80% of vent area with a piece of flat sheet metal.

e.Furnace should cycle off within 2 minutes. If gas does not shut off within 2 minutes, determine reason draft safe-

guard switch did not function properly and correct condi- tion.

f.Remove blockage from furnace vent elbow.

g.Switch will auto-reset when it cools.

h.Re-install vent connector.

NOTE: Should switch remain open longer than 3 minutes, furnace control board will lockout the furnace for 3 hours. To reset furnace control board, turn thermostat below room temperature or from HEAT to OFF and turn 115-v power OFF, then back ON.

3.Check Pressure Switch(es)

This control proves operation of the draft inducer blower.

a.Turn off 115-v power to furnace.

b.Disconnect inducer motor lead wires from wire harness.

c.Turn on 115-v power to furnace.

d.Set thermostat to “call for heat” and wait 1 minute. When pressure switch is functioning properly, hot surface ig- niter should NOT glow and control diagnostic light flashes a status code 32. If hot surface igniter glows when inducer motor is disconnected, shut down furnace imme- diately.

e.Determine reason pressure switch did not function prop- erly and correct condition.

f.Turn off 115-v power to furnace.

g.Reconnect inducer motor wires, replace outer door, and turn on 115-v power.

h.Blower will run for 90 seconds before beginning the call for heat again.

i.Furnace should ignite normally.

Step 5 — Checklist

1.Put away tools and instruments. Clean up debris.

2.Verify that switches for LHT and OFF-DELAY are blower OFF-DELAY are selected as desired.

3.Verify that blower and burner access doors are properly in- stalled.

4.Cycle test furnace with room thermostat.

5.Check operation of accessories per manufacturer￿fs in- structions.

6.Review User’s Guide with owner.

7.Attach literature packet to furnace.

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Contents Ama Furnace Reliability Hazard Safety ConsiderationsCUT Hazard Dimensions IntroductionClearances to Combustibles Electrostatic Discharge ESD Precautions Procedure Codes and StandardsGeneral LocationCarbon Monoxide Poisoning and Unit Damage Hazard FIRE, Injury or Death Hazard Fire HazardProperty Damage Hazard Location Relative to Cooling EquipmentAIR for Combustion Ventilation Furnace Corrosion HazardCarbon Monoxide Poisoning Hazard Outdoor Combustion Air MethodAir for Combustion, Ventilation, and Dilution for Outdoors Installation Upflow InstallationDownflow Installation Horizontal InstallationFIRE, EXPLOSION, and Carbon Monoxide Poisoning Hazard Suspended Furnace SupportPlatform Furnace Support Roll-Out ProtectionOpening dimensions In. mm Duct FlangesHorizontal Unit Suspension Filter Arrangement Carbon Monoxide Poisoning Hazard AIR DuctsGeneral Requirements Ductwork Acoustical Treatment Supply Air ConnectionsFurnace Air Delivery CFM With FilterSpeed External Static Pressure IN. WC Size Inlet Air Delivery CFM With Filter* Downflow FurnacesReturn Air Connections GAS Piping Fire or Explosion HazardUpflow Return Air Configurations and Restrictions Maximum Capacity of Pipe Furnace Damage HazardWiring Electrical Connections Electrical Shock HazardElectrical Shock and Fire Hazard Furnace MAY not Operate HazardBOX Relocation Electrical DataElectrical Connection to J-BOX Power Cord Installation in Furnace J-BOX BX. Cable Installation in Furnace J-BOXElectrical Box on Furnace Casing Side. See Fig Fire or Electrical Shock HazardTwo-Stage Furnace with Two-Speed Air Conditioner See notes 2, 11, and 12 on the page following these figures Accessories VentingGeneral Venting Requirements Masonry Chimney RequirementsChimney Inspection Chart Internal Area of Chimney Appliance Application RequirementsVent Height Upflow Application-Vent Elbow Up Downflow Application-Vent Elbow Up then Left Horizontal Left Application Vent Elbow Left Furnace Vent Diameter Vent Height Orientation INPUTBTUH/HRUsing Tin Snips to Cut Tie Points General START-UP, ADJUSTMENT, and Safety CheckBurn Hazard Start-Up Procedures AdjustmentsStage Furnace Setup Switch Description Fire and Explosion HazardAltitude Derate Multiplier for U.S.A Redundant Automatic Gas Control ValveOrifice Hole Furnace Overheating Hazard Gas Rate cu ft. /hrSeconds Size of Test Dial For Revolution Speed Selection Color Speed AS ShippedCheck Safety Controls ChecklistStage Furnace Blower OFF delay Setup Switch Desired Heating Mode Setup Switch Blower OFF Delay SECA08485 Orifice Size and Manifold Pressures In wc for Gas Input Rate A08219 A08219A Service and Maintenance Procedures IntroductionCare and Maintenance Carbon Monoxide Poisoning and Fire HazardWiring Diagram Filter Size Information IN. / MM Cleaning AND/OR Replacing AIR FilterBlower Motor and Wheel Cleaning Heat Exchanger Unit Damage HazardSequence of Operation Igniter Position-Top View58CT Thermidistat Mode Single-Stage Thermostat and Two-Speed Cooling Adaptive ModeSingle-Speed Cooling Troubleshooting Wiring DiagramsContinuous Blower Mode Troubleshooting Guide 2-Speed KitAdapter Chimneyin Usedswitch Shutoffvent Blocked Catalog No58CT---10SI