Description:
A hydronic water heater D5WSC is a liquid-based heating system that keeps the cab and sleeper warm without idling the engine.

Part Number: D5WSC
Condition: New
Manufacture/Brand: Eberspacher

Specifications D5WSC:

Voltage: 12V
Max. Heat Output: 17,000 BTU (5 kW)
Mean electr. power: 22 - 48 W
Fuel consumption: 0.05 - 0.15 gal/h (0.2 - 0.6 l/h)
Weight without cooling fluid and add on pieces: approx. (2.7 kg)
Heater model: Hydronic D5WSC
Max. Altitude: 5,000 ft (1,500 m)
Fuel: Diesel


Purpose of using D5WSC:

1. No engine idling (big one)

  • Heats the cab & sleeper with the engine off

  • Saves a lot of diesel

  • Avoids no-idle fines

  • Cuts engine wear

2. Cold-weather engine protection

  • Heats engine coolant

  • Makes cold starts easier

  • Reduces engine damage in freezing temps

  • Faster warm-up = less smoke and stress

3. Comfort while parked

  • Quiet, steady heat all night

  • More even warmth than air heaters

  • Great for sleeper berths in winter

4. Multi-use heat source

One system can:

  • Heat the cab

  • Warm the engine

  • Sometimes provide hot water (custom setups)

5. Lower operating costs

  • Burns far less fuel than idling

  • Extends engine life

  • Pays for itself over time (especially for long-haul)

6. Works in extreme conditions

  • Reliable in very cold climates

  • Used by emergency vehicles, oilfield trucks, heavy equipment


Signs of a Bad Hydronic Water Heater D5WSC:

1. No heat or weak heat

  • Cab/sleeper stays cold

  • Takes way longer to warm up than normal
     Often: glow plug, fuel delivery, or coolant circulation issue

2. Heater starts then shuts off

  • Fires up, runs a few minutes, then stops

  • Repeated restart attempts
     Flame sensor, overheat fault, low voltage, or clogged fuel screen

3. Fault codes or blinking lights

  • Controller shows error codes

  • Rapid blinking LED on the unit
     The heater is protecting itself—don’t ignore this one

4. Strong diesel smell or white smoke

  • Excess fuel smell

  • White smoke from exhaust
     Incomplete combustion, bad glow plug, or carbon buildup

5. Loud clicking, whining, or unusual noise

  • Fuel pump clicking much louder than normal

  • Grinding or squealing
     Failing pump, air in fuel line, or worn fan

6. Coolant leaks

  • Wet spots under truck

  • Sweet smell in the cab

  • Low coolant level
     Hose, fitting, or internal heat exchanger leak

7. Overheating or shutdowns

  • Unit overheats and trips off

  • Fan keeps running after shutdown
     Coolant flow problem (bad circulation pump or airlock)

8. Battery drain

  • Heater won’t start unless engine is running

  • Low-voltage shutdowns overnight
     Weak batteries, poor wiring, or heater drawing too much power

9. Soot buildup at exhaust

  • Black soot around heater exhaust
     Poor combustion—common if maintenance is overdue

10. Works sometimes, not others (intermittent)

  • Works one night, fails the next
     Electrical connections, sensors, or control module issues