York Y32 Controls, Compressors, Condenser Coils, Condenser Fans and Motors, Refrigerant Piping

246653-YTG-E-0108

to allow complete drainage. Coils in excess of 48 inches high shall have an intermediate drain pan, also fabricated of galva- nized powder painted steel extending the entire finned length of the coil to provide better water drainage. Drainage from the intermediate drain pan shall be to the primary drain pan. OPTIONAL: Drain pans shall be constructed of stainless steel. OPTIONAL: Evaporator coils shall be protected by the Technicoat 10-1 four coat process. Coils shall be dipped in a phenolic coating, which provides substantial resistance to corrosion of aluminum and copper. OPTIONAL: Copper-tube/ Copper-finned evaporator coil assemblies.

Compressors

Units shall have two (25 ton), three (30 ton) or four (40 ton) industrial duty hermetic scroll compressors, independently piped and charged. Compressor frame shall be cast iron, with cast iron fixed and orbiting scrolls. Compressors shall be internally protected with thermal pressure relief. Each com- pressor shall include a discharge line check valve.Compres- sors shall be vibration isolated from the unit, and installed in an easily accessible area of the unit.

Condenser Coils

Condenser coils shall have 3/8” seamless copper tubes, arranged in staggered rows, mechanically expanded into alu- minum fins. Coils shall be protected from hail damage with a V configuration, with individual flat coils rotated 30 from the vertical plane for each condensing circuit. Condensing coils shall have an integral subcooler for more efficient, stable operation. OPTIONAL: Condenser coils shall be protected by the TechniCoat 10-1 four coat process. Coils shall be dipped in a phenolic coating, which provides substantial resistance to corrosion of aluminum and copper. OPTIONAL: Copper- tube/Copper-finned condenser coil assemblies.

Condenser Fans and Motors

Condenser fans shall be direct drive, propeller type, discharg- ing vertically. Condenser fan motors shall be 3 phase, totally enclosed air over (TEAO) type, with built in thermal overload protection.

Refrigerant Piping

All interconnecting piping between refrigeration components shall be copper tubing with brazed joints. Each refrigerant cir- cuit shall be equipped with liquid line filter drier, and moisture indicating sight glass. Each circuit shall also have both high and low pressure switches installed on either side of the com- pressor and include shrader depressors for replacement of the pressure switches without removing charge. All small diameter distributor tubing to the evaporator coil shall be pro- tected by polyurethane sleeves over the length of the tubing to prevent the tubes from copper-to-copper contact during shipment or operation.

Hot Gas Bypass (Optional on CV; standard on VAV)

Unit shall have hot gas bypass factory installed on the lead compressor.

CONTROLS

GENERAL DESCRIPTION

Equipment with Simplicity® as standard shall be factory run- tested through the control, after the test is complete; there will be no wires to re-connect. All control wiring points shall be tested and verified through communication.

The control shall be UL or CSA recognized. The control shall be manufactured in a manufacturing facility that is certified to ISO 9001.

COMPRESSOR CONTROL

The control shall have a five-minute Anti-Short Cycle Delay to prevent excessive compressor cycling. The control shall have a three-minute minimum run time to insure that oil gets returned to the compressor each time it starts. The minimum runtime shall be programmable up to 10 minutes.

The control shall monitor the High and Low Pressure switches separately for each refrigeration circuit. The control shall have a 30 second Low Pressure Switch bypass when it starts any compressor.

A hard compressor lockout shall occur if the control detects the same switch trip three times in a two-hour window, which starts when the first trip occurs. On the first and second trips, the control will turn the compressor off and wait five-minutes after the switch re-closes, before restarting the compressor.

The control shall be capable of operating both compressors and the economizer when there is a call for both stages of cooling.

The control shall have a means of locking out mechanical compression below a programmable low ambient trip point. This must be done without adding extra components to the unit.

The control shall have a means of locking out the mechanical compression when the economizer is operating in free cool- ing mode without additional components

The control shall have a means of starting the compressor before the indoor Fan comes on w1hen operating with a Thermostat in the AUTO FAN mode.

FAN CONTROL

The control shall have fully adjustable Fan ON and Fan OFF delays for both Heating and Cooling settable at the control or via communication.

The control's default Fan OFF delay for Cooling shall be 30 seconds to take advantage of the remaining capacity in the coil after the compressor has been turned off.

92 Johnson Controls Unitary Products