TORONTO, Ont. –The inconvenient truth may be that Earth is getting warmer. But the reality is that it still gets cold in Canada during the winter. An auxiliary cab heater has proven to be among the most economical ways to provide cab comfort during the winter.

According to a study by the American Transportation Research Institute, 32% of a truck’s idle-time is spent keeping the sleeper warm.

Here in Canada, that number could be even higher.

While auxiliary heaters don’t offer the luxury of hotel-load power or cooling, they can be used in combination with other solutions to provide year-round comfort.

A well-constructed auxiliary heater from a reputable supplier such as Espar, Webasto or Teleflex can be an ideal solution for keeping warm this winter.

Brian Curliss, product manager for Teleflex Power Systems, says there are several options when choosing an auxiliary heater.

Firstly, truckers must choose between several solutions: a dieselfired heater that provides cab warmth but doesn’t warm the engine block; a heavy-duty coolant heater that circulates truck engine coolant through a heat exchanger, warming the cab and also keeping the engine block heated for easy starts in cold weather; and light-duty coolant heaters which keep the engine warm, but lack the capacity to warm the cab. Alternatively, you can opt for both a separate light-duty coolant heater for the engine and a dieselfired heater for cab warmth.

Webasto’s Josh Lupu said he often recommends combining a cab heater with a coolant heater to eliminate the need to idle the truck to warm up the engine while also keeping the driver warm.

Once you decide on the type of heater that is best for your specific use, Curliss said truckers should consider the heating capacity required of their heater.

To keep a sleeper comfortable when it’s zero degrees celcius outside, about 20 BTUs are required for every cubic foot of space.

So if you have an 80-inch double bunk sleeper with 320 cubic feet, you’ll require a heater with at least a 6,400 BTU heating capacity. In general, Curliss said a heater that pumps out 6,000-7,000 BTUs should be adequate to keep most sleepers warm. The quality of the truck’s insulation and the use of thermal curtains can also impact the heating capacity required.

A heater with a high BTU will ultimately consume more fuel, Curliss admitted, however it will also get the cab or engine warmed up more quickly than a lower-powered heater.

Another consideration is finding adequate room for installation. A heavy-duty coolant heater will need to be installed on the frame rail while most light-duty coolant heaters can go under the hood and in-cab heaters can be installed inside the cab.

Webasto’s Lupu said it’s well worth having a reputable supplier complete the installation, since there are obvious risks involved when you’re dealing with fuel lines.

However, the installation itself isn’t overly complex, he said.

By having a certified technician do the installation, you’re also protecting yourself from voiding any warranties on the unit or vehicle.

It takes an authorized technician about four hours to install an air heater, according to Curliss.

Once you’ve chosen a heating solution, it’s important to track its performance and determine a payback.

Curliss said capacity, length of time in use and cost of fuel all enter the equation when measuring return on investment.

Teleflex’s Proheat Air A2, for instance, has a capacity of 6,800 BTUs and consumes about a half-cup of diesel per hour, which is a 97% savings over idling the truck’s main engine.

Using the heater for eight hours a day, five months of the year results much they’ll save based on their maintain, needing only an annual in a savings of about US$3,200 per year if diesel costs US$4.25 per gallon, the company claims.

Espar’s Airtronic D2 can run for 21 to 23 hours on a single gallon of diesel, the company claims. It has a fuel-savings calculator on its Web site ( www.espar.com) which allows prospective customers to find out exactly how much they’ll save based on their own operating conditions.

For its part, Webasto claims its Air Top 2000 heater with a 7,000 BTU capacity burns one gallon of diesel for every 20 hours of use while it’s more powerful cousin, the Air Top 3500 uses a gallon of diesel to provide 10 hours of heating while pumping out 12,000 BTUs.

Most cab heaters are easy to maintain, needing only an annual inspection.

Lupu also said customers should choose a heater from a reputable company that will support its products through an expansive dealer network. A low-price solution may not deliver good value if it’s frequently broken down and requiring repairs, he pointed out.