AIRTRONIC D2/D4 Diagnostic and Repair Manual for Customer Service and Technical Staff

System Overview

The Espar Airtronic D2 heater is designed to lower idling by providing an alternative in-cab heat solution. It operates via controllers (Mini, Digi, or Digi-Max) that control cab temperature and offer diagnostic capabilities. The heater undergoes a diagnostic check upon startup, followed by a sequence to ignite fuel. If unsuccessful after two attempts, it sets a fault code (e.g., code 52 for failure to ignite). The unit's operation involves air flow through the combustion chamber, fuel atomization and ignition, and temperature regulation based on the set point or remote air temperature sensor for Digi/Digi-Max controllers.

Diagnostic Devices

EDITH PC-Based Diagnostics (Preferred)

• Offers full product testing and system component control for rapid fuel system priming.
• Requires EDITH PC diagnostics for ECU extraction, necessary for warranty claims.

Digi-Diagnostic Tool

• Provides basic code viewing and clearing functions.

Visual Inspection

• Fuel Pump Angle: Should be between 15 and 35 degrees. The inlet should be on the low side, and the outlet on the high side.
• Combustion Exhaust: Ensure it extends 1.5 to 2.5 inches past the rear of the cab, has no kinks or crushes, and is angled downwards at least 45 degrees.
• Airflow Intake and Exhaust: Check for obstructions or damage.
• Return Air: Ensure it's clear from obstructions for proper operation.

Fault Code / Troubleshooting

• No Communication: Check open circuit voltage, ensure proper ground and voltage, and verify continuity to the diagnostic reader.
• Over-Voltage (010): System maximum voltage is 16 volts. Causes include battery charger in boost mode or alternator overcharging.
• Under Voltage Shutdown (011): Minimum voltage is 10.5 volts. Check battery voltage and for voltage drop to the heater.
• Overheat (012, 013, 014, 015, 016): Check for excessive temperatures, clean heat exchanger, ensure proper airflow, and verify fuel pump angle.
• Glow Pin Issues (019, 020, 021): Inspect glow pin and wiring. Replace if necessary.
• Blower Motor Issues (031, 032, 033, 034): Inspect for obstructions, check motor speed, and replace parts as needed.
• Fuel Metering Pump Issues (047, 048): Check for short circuits or open circuits. Replace if defective.
• Flame Detection Issues (051, 052, 053, 054, 056, 057): Check fuel supply, measure fuel quantity, and inspect for air entry into the fuel system.

Service Information

• Fuel Quantity Test: Replace the fuel metering pump if the fuel quantity is above the specified value. Check the filter in the fuel pump and ensure correct routing and no leaks in fuel lines.
• Resistance Values: Provides resistance values for overheat sensor, glow pin, flame sensor, and fuel metering pump for troubleshooting.
• Motor Speed Test: Lists test speeds for the blower heater at different voltages for AIRTRONIC models.

Typical Non-Warrantable Repairs

Issues caused by plugged fuel filters, atomizer screens, overheating, restricted combustion intake/exhaust, carboned burner chamber, and modified parts during removal or repair.

Important Notes

• Always document fault codes before clearing them.
• Component replacement requires entering the serial number of the Espar unit into the work order.
• Ensure the visual inspection checklist is completed before beginning troubleshooting.

This manual supports service technicians and end users in North America and is not applicable to marine installations. Specifications are subject to change without notice for continuous improvement.