The Dometic 24V Relay Kit (Part# 385311959) is a critical electrical component designed to control high-voltage circuits in RV climate control systems. This relay features a 12V coil that switches 120/240V power, making it essential for controlling air conditioner compressors and other high-draw appliances. If your Dometic AC unit isn't starting, cycles erratically, or shows no response when the thermostat calls for cooling, a failed relay is often the culprit.

Key Features

• Dual Voltage Control: 12V DC coil operates 120/240V AC circuits for reliable switching in RV electrical systems
• Heavy-Duty Construction: Built to withstand the vibration, temperature extremes, and electrical demands of mobile RV applications
• Direct OEM Replacement: Genuine Dometic part engineered to exact specifications for seamless installation
• Critical Safety Component: Properly isolates low-voltage control circuits from high-voltage power circuits
• Compressor Protection: Ensures proper startup sequencing to extend compressor life and prevent electrical damage

Technical Specifications

Part Number	385311959
Coil Voltage	12V DC
Contact Voltage	120/240V AC
Relay Type	24V Control Relay
Application	RV Air Conditioning Systems
Manufacturer	Dometic

Frequently Asked Questions

How do I know if my relay has failed?

Common symptoms include: AC compressor won't start, clicking sounds from the control box without compressor engagement, intermittent cooling, or complete system failure when thermostat calls for cooling. You may also notice the fan runs but no cold air is produced, indicating the compressor isn't receiving power through the relay.

Can I test this relay before replacing it?

Yes. With power disconnected, use a multimeter to check for continuity across the coil terminals (should show resistance, typically 80-120 ohms). Then check the contact terminals - they should be open when no voltage is applied to the coil, and closed when 12V is applied. If the relay doesn't click audibly when energized or shows incorrect continuity readings, it needs replacement.

What's the difference between the coil voltage and contact voltage?

The 12V coil voltage is the low-voltage DC power from your RV's control board that activates the relay. The 120/240V contact voltage is the high-voltage AC power that flows through the relay contacts to operate your compressor. The relay acts as an electrically-controlled switch, allowing safe low-voltage control of dangerous high-voltage circuits.

Do I need any special tools to install this relay?

Basic hand tools are sufficient - typically a screwdriver and wire strippers. However, you're working with both 12V DC and 120/240V AC circuits, so proper safety precautions are essential. Always disconnect shore power and turn off the battery disconnect before working on any RV electrical components. Take photos of wire connections before removal to ensure correct reinstallation.

Why Choose Elkhart RV Parts?

We specialize in hard-to-find Dometic replacement parts that keep your RV systems running reliably. Located in Elkhart, Indiana - the RV Capital of the World - we understand the urgency when your climate control fails on the road. We stock genuine OEM Dometic parts and ship fast so you can get back to enjoying your travels. Our team knows these systems inside and out and can help you identify the exact part you need. When you need it done right the first time, trust the Dometic experts at Elkhart RV Parts.