Sec. 11.19.02.27. Heaters

A. Heaters shall be of hot water type.

B. If only one heater is used, it shall be of fresh air or combination fresh air and recirculating type.

C. If more than one heater is used, additional heaters may be of recirculating air type.

D. The heating system shall be capable of maintaining throughout the bus a temperature of not less than 50°F at average minimum January temperature as established by the National Weather Service, National Oceanic and Atmospheric Administration, for the area in which the vehicle is to be operated.

E. Heaters installed by body manufacturers shall bear a name plate affixed by the heater manufacturer, which specifies the heater rating and performance.

F. Heater hoses shall be adequately supported to guard against excessive wear due to vibration. The hoses may not dangle or rub against the chassis or sharp edges and may not interfere with or restrict the operation of any engine function. Heater hose shall conform to SAE J20C, which is incorporated by reference. Heater lines on the interior of the bus shall be shielded to prevent scalding of the driver or passengers.

G. The chassis engine shall provide inlet and outlet holes in which heavy duty cut-off valves shall be installed in accessible locations for attachment of the bus heating system water lines.

H. There shall be water flow regulating valves installed in the pressure line for convenient operation from the driver's seat.

I. Accessible bleeder valves shall be installed in an appropriate place in the return lines of the body company installed heaters to remove air from the heater lines.

J. Heater motors, cores, and fans shall be readily accessible for service. Access panels shall be provided as needed.

K. Combustion Heaters.

(1) Combustion heaters are permitted and shall:

(a) Have a switch or one-way valve installed at the fuel tank when the fuel line is pressurized to shut off the fuel to the heater in case of a broken line;

(b) Have an indicator light in the driver's compartment to alert the driver of any malfunction;

(c) Be mounted on the left side in an individual compartment opening from the outside; and

(d) Have the exhaust come out the left side under the skirt as close to the rear wheels as possible.

(2) Only combustion heaters approved by this Administration are to be installed on school vehicles.

L. Portable heaters may not be used.