KEEPING WARM

With heating solutions for RVs becoming more affordable, we investigate the diesel option

WORDS AND PHOTOGRAPHY BY GRANT HANAN

When it comes to RV travel, there is no doubt we are spoilt for choice these days. This is never more so than when trying to keep warm in your RV. In this article, we look at the trend of fitting diesel heating and why this solution is becoming increasingly popular in the market.

TYPES OF HEATING SOLUTIONS

We decided that the time had come to fit heating to our RV as an aftermarket accessory. When selecting an RV heating solution, it came down to three choices – 240v electricity, LPG gas heating, or diesel heating. We were aiming for a DIY solution so selected the diesel heating option.

WHY DIESEL HEATING IS POPULAR

Diesel vehicles and heating in Europe is nothing new. It was originally designed as a means to pre-heat engines in sub-zero climates. These designs were enhanced with heat exchangers enabling an economical, warm and safe heating solution to be brought to the market.

Technology over time has grown and adapted to motorhomes as the fuel source is already on board. Later it was extended to the boating industry and more recently to caravans and campers.

Heating demands have grown, resulting in an increased number of manufacturers. Competition has led to improved manufacturing techniques and lower costs, making the diesel heating solution now quite affordable. Manufacturers are keen to work with the RV industry and have improved their designs and specifically tailored their solutions.

With clever designs, manufacturers now make a range of products that can be adapted and used in the OE and aftermarket arenas. One big advantage diesel has over other products is the kits can be fitted by a DIYer which can save you big dollars. Once installed, the diesel heating system is a complete standalone unit and only requires connection to a 12 volt power supply via house batteries. Having the ability to heat your RV’s cabin air regardless of your location is a great advantage. Very cosy!

THE MAIN COMPONENTS

There are many components that make up the unit, so let’s take a look in detail.

DIESEL AND STORAGE

Firstly we need diesel fuel. The beauty with a motorhome is you already have diesel on board, so really it’s just a matter of gaining access to that supply. On the other hand, a caravan needs to have a tank added.

PUMP

There needs to be a pump that can deliver the diesel to the heating unit. These pumps are designed and calibrated to deliver exactly the required quantities by using a displacement dosing style of pump.

HOSING

A correctly designed hose that won’t break down is used to carry and deliver the diesel fuel to the heater.

HEATER UNIT

This is the heart of the heating solution with the type and manufacturer varying.

EXHAUSTING

Mufflers and exhaust style pipes are used to remove the combusted exhaust gases.

ELECTRONIC CONTROLS

Small micro-processors are used to control the system. Signals are then sent to the supply pump, the heater unit and the fan module which controls the diesel supply and the heat energy generated.

WIRING HARNESSES

Wiring is used to connect all the components and carry the 12v power from on-board batteries to operate pumps and valves.

DUCTING AND OUTLETS

Ducting is used in a variety of ways to supply fresh air to the heaters combustion chamber.

A different style of duct is used to take ambient air within the RV to the heater unit. Additional ducting is then used to distribute the heated air to locations inside the RV.

HOW IT ALL WORKS

1 Metred amounts of fuel enter the unit from below.

2 Fresh air for combustion also enters the unit from below.

3 This ratio controlled diesel fuel and fresh air are mixed together in the combustion chamber of the heater (orange colour).

4 Using a glow pin, the mixture is ignited. Combustion takes place and heat energy is produced.

5 The heat energy is transferred to the surrounding metal heat exchanger (red colour). The spent fired mixture of diesel and air is exhausted below into the exhaust muffler system outside the RV.

6 A fan draws air from inside the RV into the heater unit (blue arrow) and this air is passed over the heat exchanger (red colour).

7 This fan-drawn air is heated as it passes over the hot metal surface of the heat exchanger, and then exits the heater unit via the air outlet (red arrow).

8 12 volt power is used to operate the fan and associated electronic modules.

In summary, we take the cold air inside our RV and blow it past a hot metal cylinder with a fan. The cold air is heated and we now get a stream of warm air. Gradually this circulated warm air continues to be warmed each time it passes the hot metal cylinder keeping the air inside our RV heated.

FACTORS TO CONSIDER

As we all use our RVs differently, the lifestyle we choose can have some bearing when it comes to selecting your heating solution. Here are some things for you to consider.

1. You need to have space in your RV for the heater unit. Unlike other heating products that require venting and have clearance requirements, diesel heaters don’t have compliance issues.

2. Allow for the extra weight required in your RV for an extra fuel source.

3. Unlike other vessels, you have flexibility for locating the diesel tank.

4. Refuelling is available wherever fuel for a diesel vehicle can be bought.

5. Diesel is economical to run.

6. Diesel heating doesn’t consume capacity needed to operate other RV appliances.

7. Kits can be bought to suit an aftermarket installation by a competent DIY installer.

8. Purchase the kit from specialists in the business with a proven track record. Confirm they offer a comprehensive warranty and guarantee, and have service agents throughout Australia.

9. Review the manufacturer’s amperage consumption on your batteries as they are not all the same.

FROM THE EXPERT – ROGER PHAIR, DIESEL HEATING AUSTRALIA

We asked Roger a couple of questions about diesel heating – here’s what he had to say.

Q: What do you consider to be the top three reasons that RVers should consider diesel heating over other forms of heating?

A: 1. Safety – It is indirect heating. This means all the combustion air is external to the living area.

2. Efficiency – A 2Kw class diesel heater can use as little as one litre of diesel every 6-8 hours and 12-14 watts (1 amph).

3. Cost and Installation – Stories of a smoky smelly heater and heaters that make a ticking noise or sound like a jet taking off can, more often than not, be attributed to poor installation. A DIYer following sound advice of fitting a quality heater will have an installation that will give years of trouble-free operation and they will always be invited to happy hour.

Q: New brands are coming onto the market, so what do you recommend an RV buyer should look for in a good diesel heater brand?

A: Since the introduction of diesel heating for the Australian RV market, the would-be purchaser has numerous options available to them. Internet purchasing has become very popular in the last ten years because of ease and price, but like anything else, warranty, service, installation advice and of course the quality of the product should be considered. Talk to the salesperson and make sure you are comfortable with their answers. Don’t be satisfied with just a good price and a box under your arm. Do your research. Talk to owners or look at forums to get an objective opinion of the diesel heaters on the market.

MYTHS BUSTED

If you’ve ever had reservations about installing diesel heating in your RV, take a look at what a Webasto expert had to say about some common myths.

Q: How would you respond to the statement “some people say that diesel heating smells”?

A: Thanks to a combination of the very precise control of our combustion process and the high quality burner technology exhaust odour is virtually unnoticeable. The exhaust byproduct from the burner cartridge is directed outside the vehicle.

Q: Although diesel heating can be installed by a DIYer, you are still using fuels and heat. If it is installed incorrectly, is there a risk I can cause a fire?

A: The combustion process is very precise and is contained within the burner cartridge. This is initiated by a glow pin as opposed to a naked flame. Due to the safety features built into the heater, if there is a fault detected during initiation or operation, the heater will shut down to avoid adding additional fuel into the burner cartridge.

CONCLUSION

With the heating solutions available for RVs nowadays you don’t need to let cold weather restrict your travel arrangements to warmer months. When an RV diesel heating installation can be completed over a weekend, you can be off on your next adventure in no time… keeping as warm as toast!

DIY INSTALL: RV HEATING

Each year, how many of us pack up and head north to escape the cold southerly winters? Well, with diesel heating fitted in your RV, you won’t need to any longer! And even better, it’s an installation that a DIYer can complete over a weekend. With a few tools and a good plan, you too can travel in comfort at any time and have the satisfaction knowing you did it yourself and saved some dollars. Follow me as I show you how we did our installation.

1 Before getting started, read the instructions and check off all of the components against the list provided. Develop a plan for completing the installation, as this is one job where careful planning will make all the difference.

2 With our installation, we chose an under-bed location as our electronics are located under seats and our pumps are beneath the fridge. When you’re looking for the best location, size it all out first. Have an idea where ducting will go, where the power supply will come from, and location of the controller. It’s also important to check under your RV for obstacles like tanks and plumbing.

3 Using masking tape, mark up the location of ducting outlets and use a hole saw to get a clean neat hole to size. Finish it off with some sandpaper.

4 Mark out a template for the heater unit location. Then check the underside for clearance and confirm that everything lines up before drilling. With such a large hole being needed, we used a jigsaw to cut the hole to size.

5 Locate the heater assembly through the floor and check for clearance. Do this step before drilling additional fastening holes which are needed to bolt the assembly in place.

6 Secure the base plate in place and connect the exhaust pipe and the fresh air combustion intake fuel line. Use the worm drive jubilee clips to attach the pipes and route the wiring to the fuel displacement pump.

7 With connection to the base plate completed, secure all pipework using the P clips provided. Have the exhaust outlet pointing away from the fresh air intake and angled towards the ground.

8 Connect the ducting intake and outlet using large hosing clamps. Then connect the wiring loom to the heater (this is a plug and play connector style). Route the wiring away from the heater unit and secure firmly.

9 Your choice of controller will determine any additional wiring required. With our unit, I needed only to make a positive and negative connection; the remaining wires are taped back out of the way.

10 Secure all wiring neatly in place to allow easy access to the fuse.

11 The controller needs to be in a convenient location. We chose to install ours next to our bed, for obvious reasons, plus we had access to 12v power close by.

12 We made our own bracket for the fuel tank and located it at the front of our RV, using the sub frame to secure it.

13 With the fuel tank bolted and the quick-release fuel line connector in place, we were ready to fill it with diesel and give it a test. We will be making an alloy cover for it shortly.

TIPS

1. Read the instructions carefully.

2. Double check clearances and the underside of panels to ensure there are no unseen obstructions.

3. Make your own templates and test they fit before cutting any holes.

4. Use dampeners and rubber fasteners in all brackets to help keep things quiet.

5. I recommend soldering power connections so they can’t work loose.

6. Use additional fasteners to secure all plumbing wiring and fuel lines.

7. Work to a methodical plan.