Peerless Furnace Manual

The Peerless Furnace is a high-efficiency heating system designed for residential and light commercial applications. This manual covers the PUREFIRE series with advanced combustion technology, modulating gas valves, stainless steel heat exchangers, and smart thermostat compatibility. Below are key sections for safety, features, installation, setup, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Installation 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Connecting Thermostat 7. Operating Modes 8. Maintenance Schedule 9. Care & Cleaning 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Stainless steel heat exchanger, Modulating gas valve, Smart thermostat interface, Pressure switches, Ignition system, Blower motor, Venting system.

Feature	Description
Heat Exchanger	Stainless steel construction for durability and efficiency
Gas Valve	Modulating valve for precise temperature control
Blower Motor	Variable speed ECM motor for quiet operation
Ignition System	Hot surface ignition for reliable starts
Pressure Switches	Safety switches to ensure proper venting
Thermostat Interface	Compatible with most smart thermostats
Venting	PVC pipe compatible for direct vent installation
Control Board	LED status lights for diagnostics
Filter System	Standard 1-inch or 4-inch media filter compatible
Efficiency Rating	Up to 98% AFUE

Installation

Unpack and inspect all components. Ensure proper clearances and location.

Position furnace: Place on level surface with proper clearances (6 inches from combustible materials).
Connect gas line: Use black iron pipe with pipe dope rated for natural gas.
Install venting: Use PVC pipe for direct vent system; maintain proper slope.
Electrical connections: Connect 120V power supply and thermostat wires.
Install air filter: Insert appropriate size filter in filter rack.

WARNING! Gas appliances can be dangerous; only qualified technicians should install. Ensure proper ventilation and gas leak testing.

First-Time Setup

Power on furnace; follow startup sequence.

Gas pressure adjustment: Set manifold pressure to 3.5" WC for natural gas.
Thermostat configuration: Connect compatible thermostat; set to HEAT mode.
Blower speed settings: Adjust dip switches for proper airflow.
Venting verification: Check pressure switch operation and vent pipe integrity.
Combustion analysis: Verify proper CO levels and efficiency.

CAUTION! Never bypass safety devices. Test carbon monoxide detectors after installation.

Specifications

Model Series: PUREFIRE PF-80, PF-90, PF-98
Input BTU: 40,000 - 120,000 BTU/hr
Efficiency: 80% - 98% AFUE
Gas Type: Natural gas or LP (with conversion kit)
Electrical: 120V, 60Hz, 1.5A
Blower Motor: ECM variable speed
Venting: 2" PVC direct vent
Dimensions: Varies by model (typically 21"W x 26"D x 56"H)
Warranty: 20-year heat exchanger, 5-year parts
Sound Level: < 65 dB

Controls and Settings

Access control board via front panel. LED status lights indicate system operation.

Control Board: POWER switch, STATUS LED, DIP switches for blower speed, pressure test ports.

Temperature Control: Thermostat settings (HEAT, OFF, FAN), temperature setpoints. Blower Settings: Adjustable speeds for heating and continuous fan. Gas Valve: Modulating control from 40% to 100% capacity. Safety Features: Rollout switches, pressure switches, limit switches, flame sensor.

Connecting Thermostat

Compatible with most 24V thermostats including smart models.

Turn off power to furnace before wiring.
Connect thermostat wires to control board: R, C, W, G, Y terminals.
For smart thermostats: Connect C wire for continuous power.
Configure thermostat for conventional gas heat system.

Tip: Use 18-gauge thermostat wire for best performance.

Operating Modes

Supports multiple operating modes for comfort and efficiency.

Heating Mode: Primary operation; maintains set temperature.
Fan Only: Continuous or intermittent blower operation.
Modulating Operation: Automatically adjusts flame height for precise temperature control.
Standby Mode: System ready but not actively heating.
Error Mode: Lockout with diagnostic codes displayed.

WARNING! Do not attempt to override safety controls. Contact professional service if system locks out repeatedly.

Maintenance Schedule

Regular maintenance ensures optimal performance and safety.

Frequency	Maintenance Task
Monthly	Check and replace air filter if dirty
Annually	Professional inspection and cleaning
Annually	Check gas pressure and combustion
Annually	Inspect heat exchanger for cracks
Annually	Clean blower assembly and motor
Annually	Check vent system for obstructions

Care & Cleaning

Turn off power and gas supply before cleaning. Use soft brush and vacuum for dust removal.

CAUTION! Never use water or chemical cleaners on electrical components. Keep area around furnace clear of combustible materials.

Regulatory Information

ANSI Z21.47: Certified for natural gas and LP operation. UL listed for safety. Meets DOE efficiency standards. Copyright © 2025 Peerless Heating Systems; all rights reserved. For technical support, visit www.peerlessfurnace.com or contact 1-800-555-HEAT.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Furnace won't start	Power, thermostat, gas supply	Check circuit breaker; verify thermostat settings; ensure gas valve open.
No heat	Ignition, gas valve, filter	Check for spark at igniter; verify gas pressure; replace dirty filter.
Short cycling	Dirty filter, limit switch	Replace air filter; check for blocked vents; verify proper airflow.
Blower not working	Motor, capacitor, control board	Check for power to motor; test capacitor; inspect control board.
Error codes flashing	Various system faults	Refer to diagnostic code chart in service manual; reset if safe.

Reset: Turn power off for 30 seconds then restart.

Service: 1-800-555-HEAT; www.peerlessfurnace.com