Intertherm Electric Furnace Service Manual

The Intertherm Electric Furnace is a high-efficiency heating system designed for residential and light commercial applications. This manual covers installation, operation, maintenance, and troubleshooting procedures for various Intertherm electric furnace models. Below are key sections for safety guidelines, technical specifications, installation procedures, operation instructions, maintenance schedules, and troubleshooting guides.

1. Safety Precautions 2. Technical Specifications 3. Installation Procedures 4. Electrical Connections 5. Operation Instructions 6. Maintenance Schedule 7. Component Replacement 8. Troubleshooting Guide 9. Wiring Diagrams 10. Parts List 11. Warranty Information

Safety Precautions

Critical safety information for installation, operation, and maintenance of Intertherm electric furnaces.

Hazard	Precaution
Electrical Shock	Disconnect power before servicing; use lockout/tagout procedures
High Temperature	Allow furnace to cool before handling components
Fire Hazard	Keep combustible materials away from furnace
Component Damage	Follow proper installation and maintenance procedures
Personal Injury	Wear appropriate PPE during servicing

Technical Specifications

Detailed specifications for Intertherm electric furnace models.

Voltage: 208/240V AC, 60Hz
Heating Capacity: 5kW to 20kW range
Airflow: 400-1200 CFM depending on model
Maximum Temperature Rise: 30-70°F
Sequencer Stages: 2 to 5 stages based on model
Blower Motor: Multi-speed PSC or ECM
Filter Size: Standard 16x20x1 inch or custom sizes
Dimensions: Varies by model (typically 21"W x 21"D x 49"H)

Installation Procedures

Step-by-step installation instructions for proper furnace setup.

Location Selection: Choose well-ventilated area with adequate clearance
Mounting: Secure furnace to floor or platform using appropriate hardware
Ductwork: Connect supply and return ducts following local codes
Electrical: Route power wiring through approved conduit
Thermostat: Install compatible thermostat with appropriate wiring
Final Check: Verify all connections and clearances before power-up

WARNING! Installation must comply with local building codes and NEC requirements. Only qualified technicians should perform installation.

Electrical Connections

Proper wiring procedures and electrical requirements.

Connection	Specification
Line Voltage	208/240V AC, 60Hz single phase
Circuit Breaker	Dedicated double-pole breaker per model requirements
Wire Size	10-6 AWG copper based on amperage and distance
Grounding	Proper equipment grounding required
Low Voltage	24V AC thermostat circuit

CAUTION! All electrical work must be performed by licensed electricians following local codes.

Operation Instructions

Proper operation procedures and control settings.

Power On: Ensure main power switch is in ON position
Thermostat Setting: Set desired temperature on thermostat
Mode Selection: Choose HEAT mode for furnace operation
Fan Control: Select AUTO or ON for continuous operation
Temperature Adjustment: Adjust thermostat to desired comfort level
System Monitoring: Observe normal operation cycles

Note: Allow furnace to complete heating cycles without interruption for optimal performance.

Maintenance Schedule

Recommended maintenance intervals and procedures.

Maintenance Task	Frequency	Procedure
Filter Replacement	Monthly	Replace or clean air filter
Visual Inspection	Quarterly	Check for debris, corrosion, damage
Electrical Check	Annually	Verify connections and voltage
Component Cleaning	Annually	Clean blower assembly and heating elements
Professional Service	Annually	Comprehensive inspection by qualified technician

Component Replacement

Procedures for replacing major furnace components.

Heating Elements: Disconnect power, remove access panel, replace elements
Sequencers: Label wires, remove old sequencer, install replacement
Blower Motor: Remove blower assembly, replace motor, reassemble
Control Board: Document wiring, remove old board, install new board
Limit Switches: Test continuity, replace faulty switches

WARNING! Always disconnect power before replacing components. Use only manufacturer-approved replacement parts.

Troubleshooting Guide

Common problems and solutions for Intertherm electric furnaces.

Symptom	Possible Cause	Corrective Action
No Heat	Power loss, tripped breaker, thermostat issue	Check power source, reset breaker, verify thermostat settings
Insufficient Heat	Dirty filter, faulty elements, airflow restriction	Replace filter, test elements, check ductwork
Frequent Cycling	Dirty filter, oversized unit, thermostat location	Clean filter, verify sizing, relocate thermostat
Blower Not Working	Motor failure, capacitor issue, control problem	Test motor, check capacitor, inspect control board
Strange Noises	Loose components, bearing wear, debris	Tighten hardware, lubricate bearings, remove debris

Wiring Diagrams

Reference wiring diagrams for proper electrical connections.

Main Power Wiring: Line voltage connections and circuit protection
Control Circuit: Low voltage thermostat and control wiring
Sequencer Wiring: Heating element staging and timing
Blower Motor: Multi-speed connections and capacitor wiring
Safety Devices: Limit switches and overload protection

Note: Refer to specific model wiring diagram for exact connections.

Parts List

Common replacement parts for Intertherm electric furnaces.

Part Number	Description	Application
INT-HE5K	5kW Heating Element	5kW furnace models
INT-SEQ2	2-Stage Sequencer	Multi-stage control
INT-BLM1/3	1/3 HP Blower Motor	Standard blower replacement
INT-CAP10	10 MFD Capacitor	Blower motor capacitor
INT-LIMIT	High Limit Switch	Temperature safety control

Warranty Information

Manufacturer warranty coverage and terms.

Heat Exchanger: Limited lifetime warranty
Functional Parts: 5-year limited warranty
Labor: 1-year limited warranty
Registration: Required within 60 days of installation
Exclusions: Damage from improper installation or maintenance

For warranty claims, contact Intertherm Customer Service at 1-800-INTERTHERM or visit www.intertherm.com