PRTC Executive Director: Air Conditioning on Buses

Worried about the air conditioning on Potomac Rappahannock Transit Commission buses in Prince William County? Executive Director Al Harf addresses the situation in his latest service update message from June 13.  

More messages from Harf can be found on PRTC's website. 

Before the onset of the warm weather, all of PRTC’s buses are put through a systematic campaign to insure that the air conditioning is in good working order.  In addition, with the onset of warm weather, all operators are required to verify that the bus air conditioning is working before the bus leaves PRTC’s bus yard. 

 If an air conditioning unit stops working during a trip, the operator is to inform PRTC’s dispatch office, and the dispatcher will send out a stand-by bus, provided one is available, to meet the passengers and continue the rest of the trip.  If no stand-by buses are available, the operator may open the passenger windows on Orion and Gillig model buses; however MCI buses – the majority of PRTC’s commuter bus fleet – are manufactured with windows that can be opened only in an emergency, and MCI buses cannot be driven with passenger windows open for safety reasons.  

As a result, if the a/c breaks down on an MCI bus, the operator is instructed to open both roof hatches and the window next to the steering wheel in order to circulate air as much as possible.   PRTC is currently updating its policy to require operators to inform passengers before they board if the air conditioning is not working so passengers can decide whether to board or wait for the next bus. 

Sometimes passengers believe that the a/c isn’t working well, or isn’t working at all, when in fact the unit is working as designed.  Allow me to explain.  The air conditioning unit on a bus functions differently than those in your personal vehicle or your home.  On your vehicle or home air conditioning units, you can turn the dial to the highest setting or select a specific temperature, and the unit will continue working until you change the setting or until that temperature is reached.  However, bus air conditioning units are designed to lower the temperature by at least 20 degrees Fahrenheit.  So if the outdoor temperature is 100 degrees, a bus air conditioning unit is working property if it cools the bus to 80 degrees.

Here are a few other factors that contribute to comments that the air conditioning isn’t working well: 

• During pick-ups and drop-offs, the door is frequently being opened, allowing cool air to escape.  The door has such a large effect on the temperature that some passengers have commented that their bus is cool once it reaches Prince William County – the result of the door being shut while the bus was traveling out of the city.

• OmniRide buses seat a maximum of 57 passengers and can carry still more if standees are present.The body heat generated by so many people in a confined space raises the temperature and, as a result, it will take the a/c unit longer to cool the bus.

Please continue to let us know what issues concern you.  All comments should be directed to our Customer Service office at Omni@OmniRide.com or 703-730-6664 or be submitted by completing the online Customer Comment form so they can be properly logged and tracked for follow up.

Regards,

Alfred Harf

Executive Director