Most of us can find plenty of ways to waste a buck, but one of the very best is to idle an engine unnecessarily. On a per-truck basis, the cost averages about $2600 a year, and not just in extra fuel: one of the best ways to ruin an engine’s long-term health is to let it idle for long stretches of time. Fouled injectors are the least of the wear problems created.

According to a study done by the Center for Transportation Research at the Argonne National Laboratory in Chicago, excessive idling is a rampant problem with huge costs. Argonne scientist Dr. Jules Routbort says 311,000 of the 1.87 million class-8 trucks in the United States are likely to idle overnight-which means some 570 million gallons of diesel fuel are wasted this way every year. Add Canada’s contribution to the problem-there are 310,000 class-8 trucks in Canada, and no real reason to believe that our idling habits are any different-and, well, the costs are astounding no matter which side of the border you’re on.

And then there’s the environmental penalty. In North America, idling trucks pour out more than 6.5 million tons of carbon dioxide in a year, for example. Our kids will pay the price.

This isn’t a new problem, of course, but there are relatively painless solutions that may not be so well known. In many cases idling simply serves no purpose at all. But if you’re trying to stay warm, a variety of cab and engine heaters are on the market, and most will pay for themselves within a year or so. There are also sophisticated thermal storage units, auxiliary on-board power supplies, and plug-ins at truck stops (if you can find a parking spot).

Drivers do seem to understand this. In a recent survey, more than 80% of owner-operators and 66% of company drivers said it’s “very important” to have an auxiliary heating and/or air-conditioning system on board. That implies they know idling is bad, so they’re asking for some means of preventing it while staying comfortable themselves.

Drivers not only want to stay warm, they also want their engine to start after they’ve spent a couple of hours over steak and eggs and a shower.

One solution is obviously to leave it idling. In some cases of extreme cold their fear is real, especially if the hardware hasn’t been well maintained. If you run to the north, maintain the heck out of your engine, using the right lube for winter conditions and making sure that the batteries are up to snuff, that the fuel is clean and can be kept that way. You shouldn’t be tempted to idle an engine that starts every time.

Another interesting solution is an idle-control option offered by a couple of engine makers. These systems monitor engine temperature and battery voltage and will automatically start and stop the engine to maintain these parameters, thus keeping the engine warm enough to start and the batteries charged.

You can add a third parameter by choosing the optional bunk thermostat. The system will then cycle the engine on and off with the internal sleeper environment in mind. It may also monitor outside temperature to decide if air conditioning or heating is in order.

The benefits of this system are obvious, but there’s a cost that can range widely depending on the truck maker and the options chosen. List prices will be just under $2000 or as low as a few hundred.

COMFY CABS

Your choices are many here, but there’s a problem: it’s easy to find an auxiliary heater for either cab or engine or both, but much tougher-and more expensive-to deal with air conditioning. If you’re trying to keep the sleeper cool without excessive idling, you have two choices: the optional engine cycling control described above, or an on-board generator set or auxiliary engine.

A gen set will do much more than simply run the heater or A/C system, like running 110-volt appliances such as microwaves, TVs, and computers. The downsides are substantial, though you may be able to justify the expense-the cost can be $5000 or more, they weigh 200 to 500 pounds, and they need periodic maintenance after anywhere between 100 and 500 hours of operation. If it’s heating you want, at the other cost extreme is the simple space heater running on either 12 or 110 volts for $200 or so, but the current draw on a 12-volt system is high.

Fuel-fired add-on heaters come in two basic designs: air heaters that, as the name implies, just heat the air in the cab/sleeper; and coolant heaters, which pre-heat the engine’s coolant and allow you to shut off your engine without risk of chilling it down to a hard-to-start block of frigid metal. Many coolant heaters also provide a capability to heat the cab. Cost can be upwards of $3000.

Typically these heaters run on diesel fuel, and they’re wired into the truck’s electrical system (drawing off the battery to power circulation fans, etc.). When choosing an auxiliary heater, look for a system that offers both low fuel consumption and a low amperage draw-a low power draw means you can be confident there’ll be plenty of battery power left to start up when you’re ready to roll.

Heater output is ranked in BTUs per hour, and the numerous makes and models on the market generally range from 3100 BTU to 41,000 BTU. Bigger isn’t always better, since you could end up with costly excess capacity that isn’t doing anything for you. As a rough guide, a 6000-BTU/hour air heater will adequately heat a single bunk, while a bigger sleeper will require a higher-capacity unit.

For engine pre-heat in a class-8 truck, a 17,000-BTU/hour coolant heater can typically raise engine temperature to 100 degrees F above the outside ambient air temp in just one hour. Experts tell us that slowly heating an engine for an hour or two before starting is a much better approach than heating it more rapidly with a massively powerful unit.

ENGINE HEATERS

The coolant heater is a common choice, which can come in immersion-block or remote-mounted tank designs. The electrically powered “in-block” immersion design, seen more often on medium-duty and vocational equipment, typically fits into the freeze-plug hole in the lower water jacket, while its other end heats the coolant.

The remote-tank style is more common with class-8 equipment, and can come in an electric version that requires an external 120- or 220-volt AC plug-in, or a diesel-fired stand-alone style. The former is much cheaper, but not useful in extreme cold.

The heated coolant is circulated through the engine block by convection with the electric models or by a pump with the diesel-fueled styles, and keeps it warm enough for an easy start. Both styles aim to warm the coolant to approximately 160 F (which is near the normal on-highway operating temperature range).

There are also gasoline-fueled pre-heaters on the market, although these, of course, cannot be run from the vehicle’s primary diesel fuel tanks.

Fuel-fired tank heaters use the vehicle’s electrical system for their pumping-power needs. They come in 12- and 24-volt versions. Ideal system designs offer both low fuel consumption and low amperage draw to ensure that there’s plenty of battery power available when it’s time to crank ‘er up.

According to one vendor’s guidelines, an engine-only pre-heater for use in a class-6, -7 or -8 truck should have a capacity of 15,000 to 20,000 BTU/hour, and an efficiency rating of 75% to 85%. Remote-tank engine pre-heaters can vary in size from about nine to almost 60 pounds, depending on their thermal rating.

SAFETY FACTORS

If you’re considering a diesel-fueled engine pre-heater and/or cab heater, look for these three safety features:

o multiple overheat shutdown: a monitoring function whereby, if an overheat were to occur, the heater would automatically switch off;

o high/low voltage shutdown: low-voltage detection protects against battery drain and ensures there’ll always be enough reserve power to start the vehicle; high-voltage detection protects the heater’s electrical components from damage;

o no-start safety period: this will automatically switch off the heater if it fails to ignite.

No matter how you propose to limit engine idling, the first step should be to figure out how much of it there is and what it’s costing. Your engine’s “black box” can tell you, and armed with that information you can devise a plan of attack-at a price that’s correctly matched to the cost of the problem.

There’s not much point spending several thousand dollars per truck on a solution to a problem that only costs you a few hundred. Idling is bad, for sure, but bankruptcy’s worse.