Climate Control at Idle.

THE PRIMARY REASON A DRIVER IDLES AN ENGINE IS TO KEEP THE CAB CLIMATE COMFORTABLE AND THE ENGINE WARM, BUT IDLING IS NOT ALWAYS THE BEST WAY TO GET THE JOB DONE.

Old habits are hard to break. Take, for instance, idling the engine to keep it and the cab warm. Sure there may be some

Most fleets understand the negatives associated with excessive idling but may still have not fully investigated the benefits of alternatives. Auxiliary engine and cab heaters have been around for quite awhile. They provide a viable option to idling, but since it is at additional cost up-front, some fleets have hesitated. But what about payback? Two of the major manufacturers of auxiliary units talk about some of the far-reaching cost and environmental benefits.

Idling, at issue

Franz Neumeyer, vice-president and general manager for Webasto Thermosystems, Inc., says, "One of the major issues the trucking industry is poised to address is unnecessary idling. Unnecessary idling spikes maintenance and operating costs, wastes fuel, contributes to our dependence on foreign oil, pollutes the environment, contributes to driver fatigue and reduces safety. These four primary target groups -- fuel, driver comfort, maintenance cost and emissions -- can be addressed by using auxiliary engine and air heaters."

It is no secret that fuel costs can be lowered by limiting idle. A 1999 study conducted by Argonne National Laboratories for the U.S. Department of Energy (DOE) points to auxiliary heating systems for both truck cabs and engine blocks as an effective anti-idling solution. Per truck, such systems can save 1,230 gallons of fuel annually and several thousand dollars in maintenance costs. Auxiliary engine and cab heating and cooling systems use one-tenth the fuel needed by an idling engine.

Neumeyer points to another issue, driver shortages, as a reason to look at auxiliary heating and cooling. He says, "Qualified drivers often move from company to company to find the best-paying jobs. Progressive fleets are seizing a competitive advantage by spec'ing their trucks with comfortable sleepers and seats, air ride suspension for reduced vibration, noise inhibitors and, among other amenities, auxiliary cab heating and cooling systems."

Noting that fatigue is another issue with which drivers must contend and citing diesel engine noise as a sleep inhibitor, Neumeyer claims auxiliary heating and cooling systems can eliminate some of the external elements that deprive truck drivers of sleep. The noise and vibration of an idling diesel engine can impair a good night's rest.

The opportunity to lower maintenance costs is another reason a fleet may want to specify auxiliary engine and air heater systems. Lowering idle time reduces the stress placed on engine lubricant and components. Neumeyer says that limiting idle time lessens the overall wear and tear on the engine and air conditioning compressor, which at idle are working under conditions for which they were not designed.

Emission control remains an issue for North America. A growing number of U.S. states and Canadian provinces are adopting anti-idling regulations, stiffer fines and penalties for unnecessary idling. Add to that increased fuel prices and you find a growing interest in engine pre-heat and cab heat systems. Society also profits from idle limiting. Less idle time means lower emissions at truckstops and city environments.

Other benefits have been noted. "Some fleets' human resource departments have become the unanticipated beneficiaries of our system," says Neumeyer. "They have found that the auxiliary units are a driver incentive because they offer increased comfort for the driver. In addition, the fleet is running cheaper, with better rates and is able to offer idling limiting bonuses to drivers."

Ensuring start-ups

Matthew Frais, Engineering manager for Espar Heater Systems, says, "Years ago a large number of coolant heaters were used to heat both the engine and sleeper, simultaneously. To heat the sleeper, coolant was circulated through the vehicle exchanger and the vehicle fans were run. In some cases, this type of heating system is still used today. However, there are many negatives associated with the system. The engine is heated continuously all night. This allows the oil to become thin and drain out of the cylinders, which may cause damage on engine start-up. Also, the vehicle fans may draw anywhere from five to 15 amps of power from the batteries. By morning, the batteries may not be able to start the truck."

A compact coolant and air heater can be used to heat the sleeper, while a small coolant heater may be used to preheat the engine. The air heater runs all night, using only one to two amps of power. It is thermostatically controlled and produces very little noise. The coolant heater is switched on, using a timer, one hour before engine start-up. The total power consumption of this system is less than 20 percent of that of a large coolant heater system.

Today's engines don't require the amount of pre-heating that their predecessors did. Most start up easily at zero degrees F. without a problem. For applications were vehicles need to start routinely in subzero temperatures, engine heaters are recommended.

"One of the other advantages to engine heaters is less wear on the engine when it starts pre-heated," says Frais. "In addition, the driver can turn on the interior fans immediately and have heated air to defrost the windshield."

When it comes to auxiliary cab air heaters, the benefits may have even greater paybacks. Fuel savings are a concern for every fleet and limiting idle time saves fuel. Typically, a truck uses one gallon of fuel per hour while idling. Frais says, "Our heaters burn less than one gallon every eight hours. If only the money saved on fuel is considered, the payback for an air heater is between four and five months of use. After the first year, an air heater can save $2,000 per year in fuel costs per truck."

Cab air heaters also reduce the wear on the engine. Idling an engine without a load increases wear on the engine, thus, requiring more frequent maintenance. A truck equipped with an air heater is idled less, causing less engine wear and runs fewer hours. This means it requires less than an idling truck. Less time in the shop and more time on the road means more money for the fleet.

Frais also notes that many fleets are concerned with emissions related to excess idling. He points out that cab air heaters that eliminate idling greatly decrease emissions and the pollution they cause.

The anti-idling issue throughout North America, which includes legislative concerns in non-attainment areas, are going to be an even bigger concern in the future. While enforcement of anti-idling legislation has been erratic in the past, it is likely that enforcement will increase.

Espar heaters can be factory installed on many vehicles, Volvo, Freightliner, Kenworth and Peterbilt, to name just a few. There is also a large aftermarket installation and support network. In addition, Espar will send installation experts to train technicians at fleets that are installing several heaters. The units require little maintenance, but should be run 20 minutes per month in the warmer months.

AUXILIARY "COOL"

Here's an option for cab cooling that works with the engine off. Taylor Made Environmental has recently introduced a new series of ductable, self-contained air conditioning units suitable for commercial truck applications. The new ASC-series vehicular systems are marketed under the Cruisair brand name.

The self-contained units can be mounted in the undercarriage or in a storage compartment or closet inside the vehicle. All system components, including compressor, condenser, evaporator and electrical wiring are contained in a single, compact, low-profile chassis. Return air is ducted or pulled directly across the evaporator coil and discharged through flexible ducts or smooth rigid ducts for discharge in one or more areas.

The units are designed with integral electrical heating elements offering either 1.5 or 2.5 KW of heating capacity. They are available in vertical or horizontal configurations in 10,000 and 14,000 BTU capacities, with direct or ducted condenser discharge and evaporator discharge from the top or side of the unit. The new systems are designed to be used with programmable electronic control. A pair of pre-wired plugs makes for an easy error-free hook-up. Mechanical controls are available on request.

The Cruisair units are engineered to cool at rated output even under the most harsh desert-like conditions with ambient temperatures over 120 degrees F. Standard models run on 115V power, but 230V systems are available on special orders.

INSPECTION TIPS

Most auxiliary coolant heaters are very low maintenance, but to ensure long life and low maintenance, a few maintenance checks should be made prior to the start of the heating system. Webasto Thermosystems, Inc. has put together a list of tips for check-ups.

Inspect auxiliary coolant heaters for proper functioning and possible tune-up according to the manufacturer's instructions. Webasto recommends running auxiliary heaters a minimum of 10 minutes at least once a month during the non-heating season. This practice will keep moving parts in working order and dramatically reduce maintenance costs and prolong the life and efficiency of the auxiliary heater.

Start with a visual inspection, then check the following:

* Mounting -- Inspect mounting hardware for looseness or missing items that can cause vibration. Remove any accumulated dirt or debris from around the heater area. Make sure the area around the air intake and exhaust outlet is clean.

* Exhaust system -- Check exhaust tubing for cracks, blockages, missing sections and loose clamps. Make necessary repairs to correct areas uncovered during inspection.

* Electrical system -- Inspect fuses and switches. If needed, repair corroded or damaged wiring and connections. It is always a good idea to clean battery connections and check the condition of the vehicle's batteries. Also, coat connections with an anti-corrosive compound.

* Fuel system -- Inspect the system for leaking or damaged fuel lines, clamps and connections. Check fuel lines for proper routing. Make sure they are securely attached to the vehicle along their total length. Do not allow fuel lines to come into contact with hot surfaces or moving parts. Replace the fuel filter and make necessary repairs as needed.

* Coolant system -- Inspect the system for leaking or damaged coolant lines, clamps and connections. Check coolant lines for proper routing, make sure they are securely attached to the vehicle. Inspect the coolant circulation pump for damage or seal leakage. Again, make repairs as needed.

After the inspection and repairs have been done, run the auxiliary heater to further diagnose its present condition, Before running the heater, make sure any coolant valves that may have been closed during the warmer months are now open.

Depending on the manufacturer of the auxiliary heater, you may be advised to perform a tune-up of the unit. This may include checking and adjusting certain internal items such as fuel pump pressure. Replacing fuel nozzles and cleaning carbon deposits out of the combustion chamber may also be required.

Keep the manufacturer's service manuals close at hand for information about inspection, diagnostics and repairs. Always follow the auxiliary heater manufacturer's recommended procedures.