Proheat Diesel Coolant Heater Programming

The Proheat diesel engine coolant heater is 30,000 BTU and puts out a lot of heat for something the size of a bread box. The first thing that impressed me was the O2 sensor built in to control the fuel and air mixture. The exhaust is extremely clean compared to other manufacturer’s heaters I’ve experienced.

The components come apart in modules for easy repair and servicing which we have not had to do yet. The programming for the Proheat is simple using the controller. The start times can be set at three different times of the day along with the duration and any day of the week you want.

We set all of our timers early in the morning and early afternoon depending when the drivers leave so they are consulted on what times work for them. Usually between 1.0 to 2.0 hours Monday to Friday and off for the weekend. The one issue we have been experiencing is the batteries are going dead if the bus sits for 3 to 4 days and the heater is working those days.

With all the components turning on when the heater starts up the amp draw is around 7 amps. This is a huge draw similar to leaving the head lights on. Over a 4 hour period each day will kill the batteries which are a 3 pack of 800 cold cranking amp truck batteries. These are tough batteries and it takes a lot to take them down to a low voltage situation.

Another setting on the programming is the low voltage setting. What happens is the heater will turn off if the battery voltage goes to a preset level. Originally they were set to 9.5 volts. So we adjusted that setting to 12 volts so there won’t be a starting issue down the road. When the driver gets in to do the run and the bus does not start the dispatcher has to do a dance phoning parents and letting everyone know that the bus is not going to make it or it’s going to be very late.

Parents are very prepared for this situation and know this happens so they make there own arrangements to take their kids to school. With some experience going through this we worked with the support crew from Proheat and set the programming to make sure this type of problem does not happen. I also talk to the drivers who have these units on their bus and show them how to turn off the heater completely during a long shutdown like Spring Break. It all works out once everyone is on board.