DH30-M12 Hydronic Diesel Hot Water System with Eberspacher M12 12kW Furnace


The DH30-M12 Hydronic diesel hot water system is our largest and most powerful system providing fast heat up, high volume hot water and optional air heating.  Designed for large boats, off grid or commercial applications where larger volumes of hot water are needed. Say goodbye to the hassles, risk and cost of LPG and enjoy the benefits of hot water and air heating from one setup.


Available on backorder

SKU: DH30-M12-RV Categories: , Tags: , ,


The DH30-M12 is our largest and most powerful hydronic system for applications which need a lot of hot water and have space for a larger system.

The awesome M12 furnace from Eberspacher modulates it’s heat output from 1.2 to 12kW, so the DH30-M12 works to avoid excessive cycling, but can provide a lot of heat when needed.

The DH30-M12 is sold pre assembled and tested for easy installation. The kit includes the genuine Eberspacher installation kit with wiring, fuel line, exhaust, inlet air silencer and on/off switch.  The Eberspacher Easy Start Select controller can also be purchase separately.

The DH30-M12 has the following features

  • All 316 stainless steel, suitable for boats, commercial kitchens, food trucks etc.
  • Insulated dual skin tank retains heat for efficient operation
  • Pre assembled and tested for easy installation
  • Fast heat up time, around 8min from cold
  • Integrated air heating (optional)
  • Includes tempering valve to ensure hot water is always delivered at safe temperatures
  • Watermark approved plate heat exchanger and tempering valve meet regulatory requirements for installation in domestic hot water systems.

Pair the DH30-M12 with one or more Bricor Elite shower head for a luxurious 4-5L/min showers.

By adding in a Kalori fan heads, the DH30-M12 diesel hot water becomes an effective air heater, and can be the heart of an extensive hydronic system including air heating, heated towel rails, radiator panels or underfloor heating.

System Performance 

Time to useable hot water from cold start: 8min

Time to fully hot: 12min

Regeneration time between showers: 4min

Length of shower assuming 30 degree temp rise using Dieselheat shower heads:

Bricor UltraMax 2.5L/min @ 40PSI: >15min

Bricor Elite 4L/min @ 40PSI:  >15min

Length of time the system can achieve a 30 deg temperature rise:

4L/min – >15min

5L/min – >15min

6L/min – >10min

These numbers are all affected by ambient temperature, installation layout and assume no concurrent air heating, so should be taken as a guide.

See here for more information on the DH Hydronic Series

The pre-assembled and tested hot water system base kit includes:

  • insulated 30L hot water tank
  • mounting bracket
  • Eberspacher diesel hot water furnace
  • combustion air silencer
  • exhaust system
  • tempering valve
  • wiring loom
  • fuel pump and fuel line
  • on/off toggle switch

Note: the system is not shipped with glycol. The purchaser is required to fill the tank using a standard automotive corrosion resisting glycol mix.

Useful Dimensions

Bare Tank including cap:

500W x 320H x 270D

Tank with tempering valve and furnace installed:

550W x 320H x 420D

Full system allowing for install brackets, furnace and plumbing fittings (required space):

630W x 320H x 420D

Note: Allow space or access above to fill the tank with coolant.

DH30 Installation Instructions

DH Hydronic Series Operator Manual 

Eberspacher D5E HS3 Technical Manual

Eberspacher D5E HS3 Technical Manual

All water heaters sold by Dieselheat carry 24 MONTHS warranty from date of purchase. Warranty is return to base which means you are responsible for returning any defective heaters to us for repair.

If you have an issue every attempt will be made to fix it via phone or email. Warranty is on heaters only and does not cover any issues caused by installations performed by the customer or other parties. If we can’t fix any issues with heater operation over the phone or email then the unit and possibly other parts as we suggest to you depending on the issue must be returned to us using an Australia Post air bag at your expense.

On arrival at our premises we will set the unit up on our test bench to ascertain what problem has occurred. Any defects or issues with the heater will be fixed free of charge and the unit will be shipped back to you at our expense. If the unit operates without any problems it will be deemed an installation problem and this is not covered by warranty. Any costs involved in returning the unit to the customer is at your expense.

Please do not try to disassemble the heater yourself whilst it is still under warranty without consulting with Dieselheat.

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