1976 Hydro Flame HF 12 Furnace Manual

The 1976 Hydro Flame HF 12 is a compact, efficient furnace designed for RV and mobile home applications. This natural gas/propane furnace features a 12,000 BTU output, electronic ignition, built-in safety controls, compact dimensions for easy installation, and durable steel construction. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Steel combustion chamber, electronic ignition system, thermostat control, gas valve, blower motor, exhaust vent, and safety shut-off switch.

Installation

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

1. Select location: Choose area with adequate combustion air and proper venting access.
2. Mount furnace: Secure to floor or wall using provided brackets.
3. Connect venting: Install 3-inch vent pipe to exterior with proper slope.
4. Connect gas supply: Use approved gas line with shut-off valve.
5. Wire electrical: Connect 12V DC power supply with proper fuse protection.

WARNING! Installation must comply with local codes. Use only certified gas fitters for gas connections.

First-Time Setup

Complete installation checks before initial startup.

1. Gas pressure check: Verify proper gas pressure at inlet (3.5" WC for natural gas, 11" WC for propane).
2. Leak test: Apply soap solution to all gas connections; check for bubbles.
3. Ventilation check: Ensure vent pipe is clear and properly installed.
4. Initial startup: Turn thermostat to call for heat; observe ignition sequence.
5. Adjust air shutter: Set for proper flame characteristics (blue flame with yellow tips).

CAUTION! Never operate without proper ventilation. Test for gas leaks before each heating season.

Specifications

• Model: Hydro Flame HF 12
• Year: 1976
• Heat Output: 12,000 BTU/hour
• Fuel Types: Natural Gas or Propane (field convertible)
• Efficiency: 78% AFUE
• Electrical: 12V DC, 2.5 Amp draw
• Vent Size: 3-inch diameter
• Gas Connection: 1/2-inch NPT
• Dimensions: 14" H x 10" W x 16" D
• Weight: 28 lbs
• Sound Level: 55 dB during operation

Controls and Settings

Thermostat control: Set desired temperature. Gas valve: Manual shut-off with pressure regulator.

Operating Controls: Thermostat, gas control knob, pilot light button (if equipped), blower switch.

Temperature Range: 50°F to 85°F adjustable. Blower Control: Automatic operation when heat call is satisfied. Safety Controls: High-limit switch, flame rollout protection, pressure switch. Gas Pressure Adjustment: Accessible through adjustment screw on gas valve.

Connecting Gas Supply

Use approved gas line materials. Natural gas: 3.5" WC inlet pressure. Propane: 11" WC inlet pressure.

1. Turn off gas supply at main valve.
2. Use pipe dope or Teflon tape on threaded connections.
3. Install sediment trap in gas line before furnace connection.
4. Install manual shut-off valve within 3 feet of furnace.
5. Pressure test all connections before operation.

Tip: Always use two wrenches when making gas connections to avoid damaging components.

Operating Procedures

Normal operation sequence: Thermostat call → ignition spark → gas valve opens → flame establishment → blower operation.

1. Set thermostat to desired temperature above room temperature.
2. Listen for ignition spark (clicking sound).
3. Observe flame through viewport (should be steady blue with slight yellow tips).
4. Blower should start approximately 30 seconds after flame establishment.
5. When thermostat is satisfied, gas valve closes and blower continues for cool-down period.
6. For shutdown: Turn thermostat to lowest setting or off position.

WARNING! Never attempt to manually light this furnace - it has electronic ignition only.

Safety Features

High Limit Switch: Shuts off gas if temperature exceeds safe limits. Flame Rollout Protection: Detects improper flame patterns. Pressure Switch: Ensures proper venting before ignition. Thermal Fuse: One-time use safety device for extreme over-temperature conditions.

Maintenance & Cleaning

Annual maintenance required before heating season. Turn off gas and electrical power before servicing.

1. Clean burners: Remove and clean with soft brush and compressed air.
2. Clean heat exchanger: Use flexible brush to remove soot and debris.
3. Clean blower: Vacuum blower wheel and housing.
4. Check vent system: Inspect for obstructions or damage.
5. Test safety controls: Verify proper operation of all safety devices.

CAUTION! Never operate with access panels removed. Replace gaskets if damaged during service.

Regulatory Information

ANSI Z21.44: Certified for recreational vehicle use. CSA 4.3: Approved for mobile home installation. This appliance must be installed in accordance with local codes, or in the absence of local codes, with the National Fuel Gas Code, ANSI Z223.1/NFPA 54. For technical support, contact Hydro Flame Customer Service at 1-800-555-HEAT.

Troubleshooting

Reset Procedure: Turn thermostat off for 5 minutes, then back on to reset safety controls.

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