Espar Heater Systems unveiled the first of its PLUS Series heater kits for school bus applications: the E-Guardian PLUS.

The PLUS Series represents the incorporation of refinements requested by customers to help improve heater efficiency and performance in market-specific kits, company officials said. School bus fleets will receive premium components in the new E-Guardian PLUS kits.

The E-Guardian PLUS 12 kW kit comes with the M-II heater, rated at 42,000 btu. The M-II includes up to six operating speeds for lower amp draw, fuel consumption and emissions, and automatic altitude adjustment for reliability.

The E-Guardian PLUS 5 kW kit, rated at 17,000 btu, includes Espar’s Hydronic D5 heater with the highest top-end heat delivery available, according to the company.

Each E-Guardian PLUS Series package includes Espar’s Multi-Max controller with a set of PC-programmable features, including automatic run times for up to four sets of on-off operations per day; a skip scheduler, allowing management to select holiday and vacation days as much as one year in advance; ambient temperature sensing to prevent heaters from running in warmer mornings; and low-voltage protection.

The Multi-Max’s parameters are entered onto a secure SD card that can be used to program multiple units with the same settings, or the card can be left in place to record heater operation functions over time. The Multi Max has been in the market for more than one year.

Additionally, fleets will receive a new auto-reset electronic impact switch. This switch replaces the former mechanical impact switch, providing auto-reset capability to ensure the heater is ready for operation every morning, even if it may have tripped during rough road operation the previous day. The E-Guardian 12 kW kit also includes a 90 degree solid exhaust elbow to strengthen a stress point in the exhaust pipe at the heater connection and make installation and maintenance easier, according to company officials.  

Both E-Guardian PLUS Series kits come with a rugged enclosure for protection and all necessary mounting hardware for installation.  

The new E-Guardian PLUS changes were incorporated at no additional cost to the end user.