We thought it would be interesting to share this installation because it includes such a wide range of equipment and was carried out on such a large motorhome. It’s certainly one of the biggest and most complex installations Dieselheat has completed in recent years.
Earlier this year, the owner of this 12m American-built motorhome contacted us looking to modernise the onboard services. Like many US-built RVs, it was originally fitted with LPG appliances for cooking, hot water and space heating. However, these systems were not compliant with Australian regulations, so the owner wanted to convert the entire coach to diesel-powered hot water, air heating and cooking.
See the video series here
Plenty of Hot Water
One of the owner’s key requirements was to have a generous supply of hot water, with the flexibility to heat it from either diesel while travelling or camping off-grid, or from 240V power when connected to mains electricity.
This made our 40-litre Surecal copper storage hot water system the ideal solution. The tank is heated by an Eberspächer 5kW Hydronic furnace or a 1kW 240V electric element, providing 40 litres of water stored at temperatures of up to 80°C. Combined with a thermostatic mixing valve, this delivers a significantly larger usable volume of hot water than a conventional 40-litre system. The system was installed with space next to it to allow the addition of a 2nd 40L tank should the owner decide even more hot water was needed.
The Best of Both Worlds for Cooking
The owner also had very specific cooking requirements.
They wanted the instant response and convenience of an induction cooktop, but because the bus doesn’t have an enormous battery bank, they couldn’t rely on induction cooking alone while camping off-grid.
The ideal solution was to install both an induction cooktop and a diesel cooker. This allows fast, efficient induction cooking whenever mains power or sufficient battery capacity is available, while the diesel cooker provides a highly efficient off-grid cooking option that requires very little electrical power.
This project gave us the perfect opportunity to install the new Wallace 3.6kW induction cooktop alongside the Wallace 1200D diesel cooker. Mounted side by side, they create a four-burner cooking arrangement while occupying a compact footprint and offering maximum flexibility.
Reusing the Original Heating Ducts
The original heating system was particularly interesting.
The factory gas heater discharged warm air into a large underfloor plenum, with floor vents distributing the heat throughout the bus.
Rather than replacing this system completely, we installed an Eberspächer D6L 6kW diesel air heater and fabricated a custom timber plenum to connect the new heater to the existing underfloor plenum.
The results exceeded our expectations. Not only did the system deliver warm air evenly throughout the entire motorhome, but it also heated the floor itself, creating a very comfortable radiant floor effect in addition to the warm air heating.
More Than 60 Hours of Installation
This was a major installation, requiring more than 60 hours of work.
The project included:
- New battery-powered electrical distribution system.
- Custom diesel fuel manifold supplying all three diesel appliances from the existing generator fuel supply.
- Installation and plumbing of the Surecal 40-litre hot water system.
- Installation of a digital thermostatic mixing valve to accurately regulate hot water temperature.
- Installation of the Eberspächer D6L air heater and custom timber plenum to utilise the original underfloor ducting.
- Installation of the Wallace diesel cooker and Wallace induction cooktop.
Wherever possible we re-used existing penetrations in the bus for the new exhasuts – meaning that the entire install required no new penetrations or repair to the paintwork.
The finished installation gives the owner a fully integrated diesel-powered heating, hot water and cooking system that is compliant with Australian requirements while providing exceptional comfort, flexibility and off-grid capability.
