American Standard HVAC YCX048G4-H Manual

The American Standard YCX048G4-H is a high-efficiency residential gas furnace with variable-speed blower technology, designed for reliable heating performance. It features a durable aluminized steel heat exchanger, electronic ignition, multi-speed ECM blower motor, integrated diagnostic controls, and compatibility with various thermostat systems. Below are key sections covering safety, features, installation, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Installation Requirements 3. First-Time Startup 4. Technical Specifications 5. Controls and Operation 6. Thermostat Connection 7. Maintenance Procedures 8. Safety Features 9. Care & Cleaning 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Aluminized steel primary heat exchanger, variable-speed ECM blower, electronic hot surface ignition, integrated control board, pressure switches, flame sensor, and condensate drain system.

Feature	Description
Heat Exchanger	Durable aluminized steel construction for efficient heat transfer
Blower Motor	Variable-speed ECM for quiet operation and energy savings
Ignition System	Electronic hot surface ignition for reliable startup
Control Board	Integrated diagnostic LED for error code display
Vent Connection	PVC venting compatible for sidewall or roof termination
Gas Valve	Modulating gas valve for precise temperature control
Filter Rack	Standard 1-inch or 4-inch media filter compatible
Pressure Switches	Ensures proper venting and safe operation
Condensate Drain	PVC connections for condensate removal
Electrical Connection	115V AC, 60Hz power supply

Installation Requirements

Unpack and inspect unit for damage. Ensure proper location with adequate clearance.

Location: Install in conditioned space with minimum clearances per manual (typically 1" sides, 6" front, 24" top).
Venting: Use approved PVC pipe for intake and exhaust; maintain proper slope for condensate drainage.
Gas Supply: Connect to natural gas line with shutoff valve; pressure test for leaks.
Electrical: Connect 115V power with dedicated circuit; ground properly.
Ductwork: Connect supply and return ducts; seal all joints.
Condensate: Route drain line to suitable drain or condensate pump.

WARNING! Installation must comply with local codes. Only qualified HVAC technicians should install this furnace.

First-Time Startup

After installation, perform startup sequence and system check.

Power on: Turn on electrical power and gas supply.
Thermostat: Set to HEAT mode and temperature above room temp.
System check: Listen for ignition sequence; verify flame establishment.
Airflow: Check supply air temperature rise (typically 35-65°F).
Venting: Verify proper exhaust flow and condensate drainage.
Settings: Configure blower speeds and thermostat parameters if needed.

CAUTION! Never bypass safety devices. If furnace fails to start, check error codes and refer to troubleshooting.

Technical Specifications

Model: YCX048G4-H
Input BTU/H: 48,000 BTU (Natural Gas)
Efficiency: Up to 96% AFUE
Blower Motor: Variable-speed ECM
Electrical: 115V AC, 60Hz, 6.5 Amps
Gas Connection: 1/2" NPT
Vent Size: 2" PVC (intake and exhaust)
Dimensions (HxWxD): 40" x 17.5" x 21"
Weight: 98 lbs
Operating Temp Range: -30°F to 150°F ambient

Controls and Operation

Integrated control board with LED diagnostic light. Access panel must be securely in place for operation.

Control Board LED Codes: Steady green = normal operation. Flashing codes indicate specific faults (see troubleshooting).

Thermostat Operation: Compatible with single-stage and two-stage thermostats. For optimal performance, use compatible American Standard communicating thermostat.

Blower Speeds: Adjustable for heating and cooling modes via dip switches on control board.

Gas Valve: Modulating operation adjusts flame height for precise temperature control.

Thermostat Connection

Standard thermostat connections (R, W, Y, G, C).

Turn off power to furnace before connecting thermostat wires.
Connect wires to control board terminals matching thermostat connections.
For two-stage operation, connect W1 and W2 terminals.
Restore power and test system operation.

Tip: Use 18-gauge thermostat wire for runs up to 100 feet.

Maintenance Procedures

Regular maintenance ensures optimal performance and longevity.

Monthly: Check and replace air filter if dirty.
Annual (by technician): Inspect heat exchanger for cracks.
Annual: Clean flame sensor with fine sandpaper.
Annual: Check gas pressure and adjust if necessary.
Annual: Inspect vent system for obstructions.
Annual: Clean condensate drain and trap.
Annual: Lubricate blower motor if required (most ECM motors are sealed).
Annual: Check all electrical connections for tightness.

WARNING! Always turn off power and gas supply before performing any maintenance.

Safety Features

Multiple safety devices protect against hazardous conditions:

Flame rollout switches: Detect flame outside heat exchanger
Pressure switches: Verify proper venting before ignition
High limit switch: Prevents overheating
Flame sensor: Confirms flame establishment
Condensate overflow switch: Shuts off furnace if drain is blocked
Door safety switch: Cuts power when access panel is removed

Care & Cleaning

Keep furnace area clean and free of debris.

Exterior: Wipe with dry cloth only.
Air filter: Replace every 1-3 months depending on usage.
Vent terminals: Keep clear of snow, leaves, and debris.
Drain line: Flush annually with water/vinegar solution.

CAUTION! Never use water or cleaning solutions on electrical components. Keep flammable materials away from furnace.

Regulatory Information

UL listed and ANSI certified. Complies with U.S. Department of Energy efficiency standards. Natural gas models designed for use with natural gas only (not convertible to LP). Manufactured to meet or exceed ASHRAE 90.1 standards. For technical support, contact American Standard at 1-800-428-4328 or visit www.americanstandardair.com.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Furnace won't start	Power, thermostat, door switch	Check circuit breaker; verify thermostat setting; ensure access panel is secure.
No heat	Gas supply, ignition	Verify gas valve is on; check for error codes; inspect flame sensor.
Short cycling	Dirty filter, limit switch	Replace air filter; check for restricted airflow; verify proper temperature rise.
Blower runs continuously	Thermostat fan setting	Set thermostat fan to AUTO instead of ON.
Error code flashes	System fault	Count flashes and refer to diagnostic chart in manual.
Unusual odors	Dust, overheating	New furnace may have temporary dust smell; persistent burning smell requires service.
Condensate leak	Clogged drain line	Clear condensate drain and trap; check slope.

Reset Procedure: Turn power off for 30 seconds, then restore. If problem persists, call for service.

Service: 1-800-428-4328; www.americanstandardair.com