York D2HE/D2HG060, D1HE/D1HG036 warranty FACTORY-INSTALLED Option, FIELD-INSTALLED Accessories

troubleshooting without affecting the normal system operat- ing pressures.

AIR FILTERS - Units are shipped with 1" throwaway filters. The unit filter racks can accommodate 1" or 2" filters without any modifications

FACTORY-INSTALLED OPTION

ECONOMIZERS: Units equipped with a factory-installed economizer option have dampers that are positioned by a spring return, fully modulating damper actuator and are capa- ble of introducing up to 100% outdoor air. As the outdoor air intake dampers open, the return air dampers close. The changeover from mechanical refrigeration to economizer operation is determined by a single input electronic enthalpy control or by a dual input electronic enthalpy control. Simulta- neous compressor and economizer operation is also possi- ble.

The single enthalpy system contains a sensor that monitors the outdoor air which automatically operates the damper actuator allowing the dampers to open or close.

The dual enthalpy system contains a second sensor that monitors both the temperature and the humidity of the return air in addition to the outdoor air sensor described for a single enthalpy system. The logic module compares the inputs from both sensors and switches to economizer operation when- ever the outdoor air is cooler than the return air for maximum efficiency of the economizer system.

The economizer is completely wired and installed at the fac- tory. Only the outdoor air hood, including its filters, need be assembled and installed in the field.

FIELD-INSTALLED ACCESSORIES

SINGLE INPUT ELECTRONIC ENTHALPY ECONOMIZER - Includes a slide-in / plug-in damper assembly with fully modu- lating spring return motor actuator capable of introducing up to 100% outdoor air, one outdoor air electronic enthalpy sen- sor and a rain hood with filters. The rain hood is painted to match the basic unit and must be field-assembled before installation. Economizer dampers are 2% low leakage type.

DUAL INPUT ELECTRONIC ENTHALPY ECONOMIZER - Includes the same damper system and rain hood with filters as described for a single enthalpy economizer except this accessory contains two enthalpy sensors. It uses a differen- tial enthalpy control that compares the outdoor air versus the return air. The logic module then optimizes the economizer operation for additional savings over the single input econo- mizer.

MOTORIZED AIR DAMPER - Includes a slid-in/plug-in damper assembly with a rainhood and filters. The outdoor air dampers open when the indoor fan motor is energized. The damper is capable of providing 0% through 100% of outdoor return air opening.

036-21216-003-A-0204

MANUAL OUTDOOR DAMPER - Provides 0% through 35% or 0% through 100% of return air opening (field adjustable). Designed for duct mounted side or bottom supply/return applications. Includes rain hood assembly and filter.

ELECTRIC HEATERS - Include nickel chromium elements, a terminal block, fuses (where required by UL), all the neces- sary connectors and hardware. All heaters utilize single point power supply hookup. Capacities from 5 KW thru 30 KW heating are available.

FUSE BLOCK KITS - These kits have a fuse box with a fuse block and fuses. They're available for all 460-3-60 volt heat- ers and 208/230-3-60 volt heaters 7 KW and smaller.

OUTDOOR THERMOSTAT - A 24-volt thermostat providing two stages of control for units equipped with electric heat accessories.

ROOF CURB - This 14" high full perimeter roof curb is shipped knocked down for field assembly and contains duct supports that can easily be

shifted for the desired unit duct arrangement. No insulated deck is required because the unit underside is insulated.

START ASSIST KIT - Provides increased starting torque for single phase units in areas with low voltage conditions. It con- tains a 12.5 OHM PTCR temperature resistor with a support clip and hardware for mounting.

LOW AMBIENT KIT - A head pressure controller maintains stable system operation by reducing the speed of the con- denser fan motor when the outdoor temperature is between 45 and 0F. Condenser fan motors with ball bearings and heavier windings are also available for these low ambient applications.

ANTI-RECYCLE TIMER - A timer to prevent the unit com- pressor from short cycling. It assures a 5-minute off-time between compressor cycles.

PROPANE CONVERSION KIT - Converts a gas-fired heater from natural gas to propane. It contains main burner orifices, a pilot orifice and a regulator spring.

LOW NOx KIT (natural gas furnaces only) - Contains five stainless steel expanded metal sheets for mounting into the heat exchanger tubes to meet the California low nitrous oxide emission requirements.

HIGH ALTITUDE CONVERSION (NATURAL AND PRO- PANE) - Provides orifices for proper furnace operation at alti- tudes up to 6000 feet. For propane applications, the propane conversion kit will also be required.

GAS PIPING - This kit contains 1/2" pipe nipples, fittings and gas cock (including panel access gaskets) required for bot- tom gas supply connection with external shut-off.

OUTDOOR COIL GUARD - Consists of grille-type sections for installation over the outdoor coil to protect it from damage.

4 Unitary Products Group