• Technical Description
• Non-Technical Description

Non-Technical Description

Everyone who drives a motor vehicle knows that the engine generates heat in the process of burning fuel (gasoline or diesel). And most know that the excess heat generated is dissipated by the engine's cooling system, consisting of water (coolant), an engine-driven water pump and a radiator. Most of the excess heat is dissipated to the outside air.

To operate efficiently and generate a minimum of air pollutants, an internal combustion engine must operate with coolant temperatures at or above 185 F. A thermostat controls this by restricting coolant flow through the vehicle radiator.

In winter, this hot engine water is used to heat the passenger compartment by diverting some of the engine coolant to a miniature radiator in the passenger compartment to the heat the incoming, cool, outside air to comfortable levels. Cabin fans blow the heated air throughout the cab interior.

Coolant is moved to both the engine radiator and, in winter, to the cabin heater by the engine-driven water pump. When the engine stops, so does the water pump and, as a result, the coolant flow. When coolant flow stops, cabin heating quickly stops.

So when drivers stop or park for any length of time in winter, they typically have two choices:

1. Shut the engine off and be cold while in the vehicle or after returning to the vehicle;
2. Idle the engine to keep the water pump at work pumping coolant to the heater, in the process wasting costly fuel and adding significantly to engine wear and air pollution.

With the AUTOTHERM® ERS, when the engine is turned off, a small high-tech pump in the vehicle's heater hose continues circulation of hot engine coolant through the vehicle's cab heating system. This small but powerful pump will circulate up to 3 gallons of hot coolant per minute, and it does it automatically each time the engine is turned off. Power consumption from the vehicle battery is practically nil, at less than 1 ampere of current.

How long will it last in a Class 6 or 7 truck? Three to 4 hours when temperatures are at the freezing level, somewhat less at colder temperatures, and somewhat more at warmer temperatures (but more on this later).

The AUTOTHERM® ERS is a patented system specifically designed for fast, easy installation and trouble-free operation in the hot, oily, wet environs of vehicle engine compartments.

A Central Control Unit, located in the truck cab constantly monitors, vehicle engine operation, battery, engine coolant temperature, heater fan settings and other factors relating to AUTOTHERM® ERS operation and displays system status on a miniature dash sub-panel.

Once the AUTOTHERM® ERS is turned on at the beginning of the heating season, no switching or adjustments of any kind are needed to operate the ERS. The driver needs only to remember to turn the engine off whenever he stops for any length of time out of the traffic. The heater continues to operate at whatever setting the driver had it prior to the vehicle being turned off with no adjustment required except to make certain the fan speed is at the low or low-medium setting. The low fan setting will allow maximum warming time without triggering the ERS's sensor that ends ERS operation to prevent battery rundown.

When the engine is turned off, no key is left in the vehicle. Instead the operator secures the vehicle by locking the doors. The operator can be gone for hours and return to a warm, snow and ice-free vehicle. If the operator is gone an extensive time-period, the system shuts itself off automatically when engine coolant temperature drops to a level where it can no longer impart 70 F interior temperature.

There is no need for the operator to be concerned that the ERS will run the battery down. The ERS automatically shuts down before battery voltage drops to levels that would make engine restart difficult.

System termination will also occur while coolant temperature is above the outside, ambient temperature. This means that the system will not circulate increasingly cooler air into the vehicle cab as the engine continues to cool to outside temperature levels.

The AUTOTHERM® ERS never cools the engine coolant down to the ambient temperature, and does not significantly increase cool-down speed over normal engine cool down speeds. What it does is redirect heat dissipation that would be lost to the atmosphere to the useful purpose of heating the cab. The vehicle operator benefits from increased comfort and safety, significant reduction in fuel consumption, reduced maintenance and increased engine life.

And environmentally conscious operators can feel good about conserving a diminishing natural resource and contributing to significant reductions in air pollution, both of which come from using the AUTOTHERM® ERS.