Holly Furnace Manual

The Holly Furnace is a high-efficiency heating system designed for residential and light commercial use. This manual covers the Holly Series furnace models with advanced combustion technology, electronic ignition, variable-speed blower motor, built-in diagnostics, safety controls, and compatibility with standard thermostat systems. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Heat exchanger, blower assembly, gas valve, electronic ignition, filter compartment, pressure switches, control board, vent connections.

Feature	Description
Heat exchanger	Stainless steel tubular design for high efficiency
Blower assembly	Variable-speed ECM motor for quiet operation
Gas valve	Electronic modulation for precise gas flow control
Electronic ignition	Hot surface igniter for reliable startup
Filter compartment	Standard 1-inch or 4-inch media filter compatible
Pressure switches	Safety verification of proper venting
Control board	LED diagnostic indicators and system controls
Vent connections	PVC pipe compatible for direct vent installation
Thermostat terminals	Standard R, W, Y, G, C connections
Service switch	External power disconnect for safety

Installation

Unpack and inspect all components. Ensure proper clearances and level mounting surface.

1. Position furnace: Place on stable, level surface with proper clearances (6 inches minimum from combustible materials).
2. Connect gas supply: Use black iron pipe with proper thread sealant. Pressure test for leaks.
3. Connect electrical: 120V AC power supply with dedicated circuit. Connect thermostat wiring.
4. Install venting: Use approved PVC pipe for intake and exhaust. Maintain proper slope.
5. Connect ductwork: Secure supply and return air ducts with proper sealing.

WARNING! Gas appliances can be dangerous; installation must comply with local codes and be performed by qualified technician.

First-Time Setup

Complete installation checks before initial startup.

1. Verify gas connections: Check for leaks with soap solution.
2. Check electrical: Ensure proper voltage and grounding.
3. Install air filter: Insert clean filter in designated compartment.
4. Set thermostat: Program desired temperature settings.
5. Startup sequence: Turn on gas supply, then electrical power.
6. Test operation: Verify proper ignition and heating cycle.

CAUTION! Never operate without proper venting and air filter installed.

Specifications

• Heating Capacity: 40,000-120,000 BTU/h depending on model
• Efficiency Rating: 80-96% AFUE
• Gas Type: Natural gas or LP (conversion kit required)
• Electrical: 120V AC, 60Hz, 5-10 amps
• Airflow: 800-2000 CFM variable speed
• Venting: 2-3 inch PVC for direct vent systems
• Dimensions: Varies by model (typically 21"W x 21"D x 56"H)
• Weight: 80-150 lbs depending on model
• Operating Temp Range: -30°F to 120°F ambient

Controls and Settings

Access control board via front panel. LED indicators show system status and error codes.

Control Board: POWER, STATUS LED (green=normal, red=fault), RESET button, DIP switches for configuration.

Thermostat Settings: HEAT/COOL mode, FAN AUTO/ON, temperature setpoints. Blower Settings: Adjustable delay timers for fan on/off. Gas Valve: Electronic modulation for precise temperature control. Safety Controls: Limit switches, pressure switches, flame sensor, rollout switches.

Connecting Thermostat

Standard 5-wire thermostat connection: R (24V power), W (heat), Y (cool), G (fan), C (common).

1. Turn off power to furnace before wiring.
2. Strip thermostat wires 1/4 inch.
3. Connect to corresponding terminals on control board.
4. Secure connections and replace access panel.
5. Restore power and test thermostat operation.

Tip: Use compatible programmable thermostat for optimal efficiency.

Operating Procedures

Normal heating cycle operation and seasonal startup.

1. Set thermostat to desired temperature in HEAT mode.
2. Furnace initiates: Inducer motor starts, pressure switch verifies, igniter heats.
3. Gas valve opens: Flame established, flame sensor confirms.
4. Blower starts: After heat exchanger warm-up delay.
5. Cycle complete: Thermostat satisfied, gas valve closes, blower continues cooling.
6. Seasonal shutdown: Turn off gas supply if not used for extended periods.

WARNING! Never bypass safety controls or operate with access panels removed.

Maintenance Schedule

Regular maintenance ensures optimal performance and safety.

Frequency	Maintenance Task
Monthly	Check/change air filter
Seasonal	Inspect vent system for obstructions
Annual	Professional inspection and cleaning
Annual	Check gas pressure and combustion
Annual	Clean flame sensor and heat exchanger
Annual	Lubricate blower motor if required

Care & Cleaning

Turn off power and gas supply before cleaning. Use soft brush and vacuum for internal components.

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

Regulatory Information

UL certified for safety standards. ANSI Z21.47 compliant for gas appliances. Meets DOE efficiency requirements. Manufactured to comply with all applicable federal and state regulations. For technical support, contact Holly Furnace Customer Service at 1-800-555-HEAT or visit www.hollyfurnace.com.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No heat	Thermostat setting, power, gas supply	Check thermostat, circuit breaker, gas valve position
Furnace won't start	Safety lockout, limit switch	Reset power, check error codes, verify filter clean
Short cycling	Dirty filter, blocked vent	Replace filter, check vent pipes for obstructions
Blower not working	Motor, capacitor, control board	Check power to blower, test capacitor, verify control signals
Gas odor	Gas leak	Immediately shut off gas supply and contact professional

Reset Procedure: Turn off power for 30 seconds, then restore.

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