Dometic ProHeat X30 Diesel-Fired Coolant Heater – 15,000–31,000 BTU/hr

Cold starts are hard on engines, and idling just to make heat wastes fuel. The Dometic ProHeat X30 solves both problems by heating your coolant loop, so you can warm the engine before startup, maintain comfortable heat while parked, and keep equipment ready in extreme weather.

Now Replacing the ProHeat X45

The ProHeat X30 is the official replacement for the discontinued ProHeat X45. It delivers the dependable performance operators trusted, while adding practical upgrades in efficiency, system integration, and diagnostics.

Where the X45 set the benchmark for diesel coolant heaters, the X30 builds on that legacy with variable heat output, closed-loop O₂ feedback control, and J1939 CAN Bus communication. In short, you get the reliability the ProHeat name is known for—now in a more compact, more capable, and more environmentally responsible package.

What the X30 does best

• Engine preheat for faster starts and reduced cold-start wear

• Cab/sleeper heat with the engine off to cut extended idling and fuel burn

• Supplemental heat while running when engine heat alone isn’t enough

• Freeze protection support for coolant loops and cold-weather operation

Variable heat output that matches demand

The X30 delivers 15,000–31,000 BTU/hr (4.4–9.1 kW) and automatically adjusts output as coolant temperature rises. That gives you quicker warm-ups, steady temperatures, and efficient operation once you’re up to temp.

Included controller + flexible operation

These units ship with the controller, giving you straightforward operation and scheduling capability (depending on how your system is configured). The heater also supports modern integration through CAN Bus/J1939, which makes it a strong fit for equipment and fleet applications that require system communication and diagnostics.

What to expect in a typical heat cycle

The X30 is designed to bring coolant up to operating temperature, then manage heat output to maintain stable performance. After a heat run, it performs a brief cool-down/purge to protect components before returning to standby. When coolant temperature drops, it resumes heating automatically.

Cab heat without killing your batteries

If your setup includes a sleeper fan or auxiliary electrical loads, best results come from maintaining strong battery health and limiting unnecessary accessories while heating. That helps preserve starting power and keeps the heating system performing reliably.

Product Specifications

• Heat Output (Variable): 15,000–31,000 BTU/hr (4.4–9.1 kW)

• Operating Voltage Range: 10–30 VDC (12V/24V systems)

• Power Consumption: up to 90W max (7.5A @ 12V, 3.8A @ 24V)

• Fuel Consumption: 0.1–0.31 gal/hr (0.4–1.17 L/hr)

• Minimum Coolant Flow: 3.0 gal/min (11.4 L/min)

• Heater Outlet Coolant Temp Range: 150–185°F (65–85°C)

• Operating Temperature Range: -40 to 185°F (-40 to 85°C)

• Operating Altitude Range: 0–15,000 ft (0–4572 m)

• Compatible Fuels: ULSD #1/#2 (including arctic blends), kerosene (K-1), jet fuels (A/A-1/JP8), biodiesel up to B20

• Ignition: Electronic spark ignition

• Heat Exchanger Capacity: 0.36 qt (0.34 L)

• Weight: 36 lb (heater only); 44 lb (with enclosure)

• Dimensions (Heater): 12.3 x 10.2 x 9.9 in (312 x 256 x 251 mm)

• Dimensions (Enclosure): 13.25 x 11.25 x 11 in (337 x 286 x 279 mm)

• Warranty: 2 years parts and labor

Kit Information (PH0375 standard kit)

• Heater: PH0350

• Installation Kit: PK3014

• Aluminum Enclosure: PK3002

• Controller: Included PK3000

Maintenance Overview

For best performance and long service life, do quick visual inspections regularly—check fuel lines, coolant hoses, wiring connections, exhaust routing, and mounting hardware. Run the heater periodically year-round to keep fuel moving through the system. On an annual basis, inspect the exhaust system and clamps, clean the enclosure carefully (avoid pressure washing), inspect/clean fuel filtration, verify battery condition and connections, and inspect the cooling system.

Downloads

• PH0375 Data Sheet (specifications & kit components)

• X30 OWNERS HANDBOOK (operation, maintenance, troubleshooting)