Cozy Furnace 355 Manual

The Cozy Furnace 355 is a high-efficiency residential heating system with 95% AFUE rating, electronic ignition, variable-speed blower, digital thermostat compatibility, built-in diagnostic system, safety shutoff features, and energy-saving modes. Designed for homes up to 2,000 sq ft, it operates on natural gas or propane with 120V AC power. Below are key sections for safety, features, installation, setup, operation, 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. Safety Features 9. Maintenance & Cleaning 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Heat exchanger, blower assembly, gas valve, control board, igniter, flame sensor, pressure switches, air filter compartment.

Feature	Description
Heat exchanger	Stainless steel primary and secondary for 95% efficiency
Variable-speed blower	ECM motor for quiet operation and energy savings
Electronic ignition	Hot surface igniter for reliable startup
Control board	Microprocessor with diagnostic LEDs
Gas valve	Modulating for precise temperature control
Air filter compartment	Standard 1-inch filter access
Pressure switches	Safety verification of proper venting
Flame sensor	Monitors burner operation
Thermostat connections	Compatible with most digital thermostats
Service switch	Local power disconnect

Installation

Unpack and inspect contents. Position in approved location with proper clearances.

Gas connection: Use approved pipe and fittings; pressure test for leaks.
Electrical connection: Connect to 120V AC dedicated circuit with proper grounding.
Vent system: Install PVC vent pipes according to local codes and manufacturer specifications.
Air intake: Ensure proper combustion air supply.
Condensate drain: Connect to approved drain with trap.

WARNING! Installation must be performed by qualified HVAC technician. Gas leaks can cause explosion or fire.

First-Time Setup

Power on furnace; follow startup sequence.

System check: Control board performs self-diagnostic; check LED status lights.
Thermostat setup: Connect compatible thermostat; set heating mode and temperature.
Gas pressure adjustment: Verify and adjust manifold pressure per specifications.
Airflow calibration: Set blower speeds for heating mode.
Test operation: Initiate heating cycle to verify proper function.

CAUTION! Ensure proper ventilation and gas connections before operation.

Specifications

Heating Capacity: 55,000 BTU/hr input
Efficiency: 95% AFUE
Fuel Type: Natural gas or propane (conversion kit required)
Electrical: 120V AC, 60Hz, 5 amps
Blower Motor: ECM variable speed
Airflow: 800-1400 CFM adjustable
Vent Material: PVC Schedule 40
Dimensions: 34" H x 17.5" W x 26" D
Weight: 98 lbs
Sound Level: < 65 dB

Controls and Settings

Access control board via front panel. Status LEDs indicate system operation and error codes.

Control Board LEDs: Power (green), Heat (yellow), Error (red), Service (amber).

Temperature Settings: Adjust via thermostat. Blower Settings: Heating speed adjustable via dip switches. Gas Pressure: Factory set; adjustable by technician. Diagnostic Codes: Flash patterns indicate specific issues for troubleshooting.

Connecting Thermostat

Compatible with most 24V thermostats. Standard connections: R, W, G, Y, C.

Turn off power to furnace before wiring.
Remove thermostat subbase to access terminal connections.
Connect wires according to thermostat manufacturer instructions.
Restore power; test thermostat operation.

Tip: Use programmable thermostat for maximum energy savings.

Operating Modes

Heating mode only; compatible with cooling when paired with AC coil.

Normal Heating: Thermostat calls for heat; furnace ignites and runs until setpoint reached.
Continuous Fan: Blower runs continuously for air circulation.
Standby Mode: System ready but not actively heating.
Error Mode: Automatic shutdown with diagnostic code when fault detected.

WARNING! Do not attempt to override safety controls or operate with error codes present.

Safety Features

Flame rollout switch: Shuts off gas if flame detected outside burner compartment. High limit switch: Prevents overheating. Pressure switches: Verify proper venting before ignition. Ignition safety: Prevents gas flow if no flame detected.

Maintenance & Cleaning

Annual professional maintenance recommended. Monthly filter inspection/replacement.

Filter: Replace 1-inch filter monthly during heating season.
Burners: Clean annually; inspect for proper flame pattern.
Blower: Clean wheel and housing annually.
Vent system: Inspect for obstructions annually.
Drain system: Flush condensate trap and line annually.

CAUTION! Turn off power and gas before performing any maintenance.

Regulatory Information

UL certified; meets ANSI Z21.47 standards. CSA certified for Canada. Manufactured to comply with U.S. Department of Energy efficiency standards. For support, visit www.cozyheating.com or contact 1-800-555-HEAT. Serial number located on rating plate inside burner compartment.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No heat	Power, thermostat, gas supply	Check power switch; verify thermostat setting; ensure gas valve open.
Furnace not starting	Safety lockout, error code	Check diagnostic LEDs; reset if safe; call for service if error persists.
Blower not running	Motor, capacitor, control board	Check power to blower; verify control signal; professional service needed.
Furnace short cycling	Dirty filter, airflow restriction	Replace filter; check vents and registers; verify proper sizing.
Unusual noises	Loose components, airflow	Inspect for loose panels; check blower wheel; verify ductwork.

Reset: Turn power off for 30 seconds then restore.

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