Ruud Silhouette II Gas Furnace Parts Manual

The Ruud Silhouette II Gas Furnace is a high-efficiency residential heating system featuring advanced combustion technology, variable-speed blower motor, electronic ignition system, multi-speed inducer motor, and comprehensive safety controls. This manual provides detailed parts identification, replacement procedures, and technical specifications for proper maintenance and repair. Below are key sections for parts overview, installation guidelines, troubleshooting, and replacement procedures.

1. Parts Overview 2. Installation Guidelines 3. Technical Specifications 4. Component Identification 5. Replacement Procedures 6. Electrical Components 7. Gas System Components 8. Venting System 9. Safety Features 10. Maintenance Schedule 11. Troubleshooting Guide

Parts Overview

Key components: Heat exchanger assembly, Gas valve, Burners, Inducer motor, Blower motor, Control board, Igniter, Flame sensor, Pressure switches, Thermostat connections.

Component	Description
Heat Exchanger	Primary and secondary heat transfer surfaces
Gas Valve	Regulates gas flow to burners
Burner Assembly	Stainless steel burners with ports
Inducer Motor	Draft inducer for combustion gases
Blower Motor	Variable-speed circulating air blower
Control Board	Main system controller with diagnostic LEDs
Hot Surface Igniter	Silicon carbide ignition element
Flame Sensor	Proves flame during operation
Pressure Switches	Verify proper venting operation
Limit Switches	High temperature safety controls

Installation Guidelines

Proper installation ensures safe and efficient operation.

Location: Install in clean, dry area with adequate clearance for service access.
Venting: Use approved PVC pipe for intake and exhaust according to local codes.
Gas Connection: Use black iron pipe with proper thread sealant; pressure test for leaks.
Electrical: Connect to dedicated 120V circuit; proper grounding required.
Ductwork: Ensure proper sizing and sealing for optimal airflow.

WARNING! Gas furnaces produce carbon monoxide; proper venting is critical for safety. Only qualified technicians should perform installation.

Technical Specifications

Input Capacity: 40,000 - 120,000 BTU/h (model dependent)
Efficiency: 90+ AFUE
Gas Type: Natural Gas (LP conversion kit available)
Gas Pressure: 3.5" WC natural gas, 10" WC propane
Electrical: 120V, 60Hz, 15A circuit
Blower Motor: Variable-speed ECM
Venting: 2" PVC pipe (intake/exhaust)
Dimensions: Varies by model (typically 21"W x 26"D x 40"H)
Weight: 120-180 lbs depending on model

Component Identification

Front access panel removal provides access to major components. Upper compartment contains heat exchanger and burners; lower compartment contains blower assembly.

Upper Section: Gas valve, manifold, burners, igniter, flame sensor, inducer motor, pressure switches, primary limit control.

Lower Section: Blower motor, control board, transformer, blower door switch, filter rack, auxiliary drain connection.

Replacement Procedures

Always disconnect power and gas supply before servicing.

Igniter Replacement: Remove burner assembly, disconnect wires, slide out old igniter.
Flame Sensor: Clean with emery cloth or replace if pitted.
Gas Valve: Shut off gas, relieve pressure, disconnect wiring and gas lines.
Blower Motor: Remove blower door, disconnect wiring, remove mounting bolts.
Control Board: Document wiring connections, remove mounting screws.

CAUTION! Use only Ruud-approved replacement parts to maintain safety and efficiency.

Electrical Components

Control board with diagnostic LED codes, 24V transformer, blower motor (ECM), inducer motor, pressure switches, limit controls, rollout switches, door interlock switch.

Control Board: Monitors system operation; flashes error codes for troubleshooting.
Transformer: Steps down 120V to 24V for control circuit.
Blower Motor: ECM technology for variable airflow and efficiency.
Inducer Motor: Creates draft for combustion process.

Tip: Check fuse on control board before replacing components.

Gas System Components

Gas valve with manual shutoff, manifold, burners, orifice holders, pilot assembly (if equipped).

Turn off gas supply at unit and upstream valve.
Disconnect union and gas line connections.
Remove manifold pressure tap plug for pressure testing.
Verify proper gas pressure: 3.5" WC natural gas.

WARNING! Always leak test after any gas connection work. Use soap solution to check for bubbles.

Venting System

PVC intake and exhaust pipes, couplings, elbows, termination kits.

Venting Guidelines: Maximum equivalent length 100 feet, minimum 5 feet. Maintain 1/4" per foot slope back to furnace. Keep intake and exhaust terminations at same pressure zone.

Safety Features

Flame rollout switches, high limit switches, pressure switches, door interlock switch, igniter safety timing, gas valve safety shutoff.

Maintenance Schedule

Annual professional inspection recommended. Monthly filter changes during heating season. Visual inspection of vent pipes and drain lines.

CAUTION! Only qualified HVAC technicians should perform internal component maintenance.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Furnace won't start	Power, thermostat, door switch	Check circuit breaker, thermostat setting, door switch engagement.
No heat	Igniter, gas valve, flame sensor	Test igniter for continuity, check gas valve operation, clean flame sensor.
Blower won't run	Motor, capacitor, control board	Check voltage to motor, test capacitor, verify control board signal.
Short cycling	Filter, limit switch, airflow	Replace filter, check limit switch, verify proper airflow.
Error codes flashing	Various system faults	Refer to control board LED flash pattern in service manual.

Reset: Power cycle unit to clear temporary lockouts.

Service: Contact authorized Ruud dealer for technical support and genuine parts.