Gaffers and Sattler U-100 Furnace Manual

The Gaffers and Sattler U-100 is a high-efficiency residential furnace with 100,000 BTU output, natural gas operation, electronic ignition, variable-speed blower motor, multi-speed settings, built-in safety controls, diagnostic LED system, and energy-saving features. Designed for standard residential installation with 120V AC power requirement. Below are key sections for safety, features, installation, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Installation Requirements 3. Initial Setup and Startup 4. Technical Specifications 5. Controls and Operation 6. Maintenance Procedures 7. Safety Features 8. Diagnostic System 9. Seasonal Operation 10. Warranty Information 11. Troubleshooting Guide

Features at a Glance

Key components: Heat exchanger, burner assembly, blower motor, gas valve, control board, filter system, venting system, and diagnostic LED.

Feature	Description
Heat Output	100,000 BTU natural gas
Ignition System	Electronic hot surface ignition
Blower Motor	Variable-speed ECM motor
Efficiency Rating	95% AFUE
Control System	Microprocessor-based control board
Safety Controls	Flame sensor, rollout switches, pressure switches
Venting	PVC pipe compatible
Filter Size	16x25x1 inch standard
Gas Connection	1/2 inch NPT
Electrical	120V AC, 60Hz

Installation Requirements

Professional installation recommended. Verify local codes and obtain permits.

Location: Install in well-ventilated area with proper clearances (minimum 1 inch sides, 6 inches front).
Gas Connection: Use approved gas pipe; pressure test required (7-inch WC natural gas).
Electrical: Dedicated 120V circuit; proper grounding required.
Venting: PVC schedule 40 pipe; follow manufacturer venting tables.
Drain Line: Install condensate drain with trap.

WARNING! Gas appliances can be hazardous; installation by qualified technician only. Ensure proper combustion air and venting.

Initial Setup and Startup

Complete installation verification before first startup.

Gas pressure check: Verify inlet and manifold pressures match specifications.
Electrical check: Confirm proper voltage and grounding.
Venting verification: Ensure proper slope and termination clearances.
System startup: Follow control board sequence; observe ignition cycle.
Temperature rise: Measure and adjust blower speed if necessary.

CAUTION! Never bypass safety controls. Test all safety functions during initial startup.

Technical Specifications

Model: U-100
Input Capacity: 100,000 BTU/h
Output Capacity: 95,000 BTU/h
AFUE Rating: 95%
Gas Type: Natural gas
Manifold Pressure: 3.5-inch WC
Blower Speeds: 4 cooling, 2 heating
Motor Type: ECM variable speed
Electrical: 120V/1Ph/60Hz
Dimensions: 44"H x 21"W x 26"D
Shipping Weight: 125 lbs

Controls and Operation

Integrated control board manages all furnace functions. Thermostat connections: R, W, G, Y, C.

Operating Sequence: Call for heat → Inducer motor starts → Pressure switch proves → Hot surface ignition → Gas valve opens → Flame proven → Blower starts after delay.

Blower Speeds: Adjust via control board dip switches (HEAT: low/high, COOL: 4 speeds). Temperature Rise: 35-65°F (adjust blower speed to achieve).

Maintenance Procedures

Regular maintenance ensures optimal performance and safety.

Monthly: Check and replace air filter as needed.
Annual: Professional inspection and cleaning recommended.
Burner inspection: Clean burners and check flame pattern.
Heat exchanger: Visual inspection for cracks or damage.
Blower assembly: Clean blower wheel and housing.
Drain system: Flush condensate trap and drain line.

Tip: Keep area around furnace clean and unobstructed.

Safety Features

Multiple safety systems protect against hazardous conditions.

Safety Device	Function
Flame Sensor	Detects burner flame; shuts off gas if no flame
Rollout Switches	Detects flame rollout; shuts down furnace
Pressure Switches	Verifies inducer operation; prevents operation if blocked
High Limit Switch	Prevents overheating; resets automatically
Gas Valve	Automatic shutoff during power outage

Diagnostic System

LED status light provides fault code diagnostics.

LED Flash Codes:

1 Flash: Normal operation
2 Flashes: Pressure switch error
3 Flashes: Rollout switch open
4 Flashes: High limit switch open
5 Flashes: Flame sense error
6 Flashes: Ignition failure
Continuous On: Control board error

Reset: Power cycle to clear non-latching faults.

Seasonal Operation

Proper seasonal preparation ensures reliable operation.

Winter Startup: Check filter, verify thermostat operation, test safety controls, inspect vent termination.

Summer Shutdown: Clean furnace, cover if not in use, verify condensate drain clear.

CAUTION! Never operate furnace without proper air filter installed.

Warranty Information

Heat Exchanger: 20-year limited warranty. Parts: 5-year limited warranty. Labor: 1-year from installation. Registration required within 60 days of installation. Warranty void if improper installation, modification, or lack of maintenance. Contact authorized Gaffers and Sattler dealer for warranty service.

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	Gas supply, ignition	Verify gas valve on, check for ignition attempts
Short cycling	Filter, limit switch	Replace dirty filter, check for overheating
Blower won't stop	Thermostat, control board	Check thermostat fan setting, control board operation
Unusual noises	Blower, inducer	Inspect blower wheel, inducer motor for obstructions
Error code displayed	Various faults	Refer to diagnostic chart for specific code

Service: Contact qualified HVAC technician for all repairs. Gaffers and Sattler Customer Service: 1-800-555-HEAT