guide specifications

Packaged Gas Heating/Electric Cooling Units Constant Volume Application
HVAC Guide Specifications
Size Range:	2 to 5 Tons, Nominal Cooling
	40,000 to 127,000 Btuh,
	Nominal Heating Input
SYSTEM DESCRIPTION
Outdoor rooftop mounted, gas heating/electric cooling unit utilizing a hermetic scroll compressor for cooling duty. Unit shall discharge supply air vertically or horizontally as shown on contract drawings. Condenser fan/coil section shall have a draw-thru design with vertical discharge for minimum sound levels.
QUALITY ASSURANCE
	A.	Unit shall be rated in accordance with AHRI Standards 210/240 and 270-1995.
	B.	Unit shall be designed in accordance with UL Standard 1995 and ANSI Z 21.47.
	C.	Unit shall be manufactured in a facility registered to ISO 9001 manufacturing quality standard.
	D.	Unit shall be UL listed and c-UL certified as a total package for safety requirements.
	E.	Roof curb shall be designed to conform to NRCA Standards.
	F.	Insulation and adhesives shall meet NFPA 90.1 requirements for flame spread and smoke generation.
	G.	Cabinet insulation shall meet ASHRAE Standard 62.2.
DELIVERY, STORAGE AND HANDLING
	Unit shall be stored and handled per manufacturer’s  recommendations.
Part 2 — Products
EQUIPMENT
	A.	General:
	Factory-assembled, single-piece, heating and cooling unit. Contained within the enclosure shall be all factory wiring, piping, controls, refrigerant  charge with R-410A refrigerant, and special features required prior to field start-up.
	B.	Unit Cabinet:
	1.	Unit cabinet shall be constructed of phosphated, zinc-coated, pre-painted steel capable of with-standing 500 hours in salt spray.
	2.	Normal service shall be through 3 removable cabinet panels.
	3.	The unit shall be constructed on a rust proof unit base that has an externally trapped, integrated sloped drain.
	4.	Evaporator fan compartment top surface shall be insulated with a minimum 1/2-in. (12.7 mm)  thick, flexible fiberglass insulation, coated on the air side and retained by adhesive and mechanical means. The evaporator wall sections will be insulated with a minimum semi-rigid foil-faced board capable of being wiped clean. Aluminum foil-faced fiberglass insulation shall be used in the entire indoor air cavity section.
	5.	Unit shall have a field-supplied condensate trap.
	C.	Fans:
	1.	The evaporator fan shall be a multi-speed, direct-drive, as shown on equipment drawings.
	2.	Fan wheel shall be made from steel, be double-inlet type with forward curved blades with corrosion resistant finish. Fan wheel shall be dynamically balanced.
	3.	Condenser fan shall be direct drive propeller type with aluminum blades riveted to corrosion resistant steel spiders, be dynamically balanced, and discharge air vertically.
	D.	Compressor:
	1.	Fully hermetic compressors with factory-installed vibration isolation.
	E.	Coils:
Evaporator and condenser coils shall have aluminum plate fins mechanically bonded to seamless copper tubes with all joints brazed. Tube sheet openings shall be belled to prevent tube wear.
	F.	Heating Section:
	1.	Induced-draft combustion type with energy saving direct spark ignition system and redundant main gas valve.
	2.	Induced-draft motors shall provide adequate airflow for combustion.
	3.	The heat exchangers shall be constructed of aluminized steel for corrosion resistance.
	4.	Burners shall be of the in-shot type constructed of aluminum coated steel.
	5.	All gas piping and electric power shall enter the unit cabinet at a single location.
	G.	Refrigerant Components:
Refrigerant expansion device shall be of the TXV (thermostatic expansion valve) or fixed orifice type.
	H.	Filters:
Filter section shall consist of field-installed, throwaway, 1-in. (25 mm) thick fiberglass filters of commercially available sizes.
	I.	Controls and Safeties:
	1.	Unit controls shall be complete with a self-contained low voltage control circuit.
	2.	Compressors shall incorporate a solid-state compressor protector that provides reset capability.
	J.	Operating Characteristics:
	1.	Unit shall be capable of starting and running at 125_F (51_C) ambient outdoor temperature per maximum load criteria of AHRI Standard 210.
	2.	Compressor with standard controls shall be capable of operation down to 40_F (4_C) ambient outdoor temperature.
	3.	Units shall be provided with fan time delay to prevent cold air delivery before the heat exchanger warms up.
	4.	Unit shall be provided with 60-second fan time delay(single phase models) or 90 second fan time delay (three phase models) after the thermostat is satisfied.
	K.	Electrical Requirements:
	All unit power wiring shall enter the unit cabinet at a single location.
	L.	Motors:
	1.	Compressor motors shall be of the refrigerant-cooled type with line-break thermal and current overload protection.
	2.	All fan motors shall have permanently lubricated bearings, and inherent, automatic reset, thermal overload protection.
	3.	Condenser fan motor shall be totally enclosed.
	4.	Evaporator Fan Motor to be ECM Motor.
	M.	Compressor Protection:
Solid-state control shall protect compressor by preventing “short cycling.”

guide specifications (cont)

	N.	Low NOx:
Shall provide NOx reduction to values below 40 nanograms/joule to meet California’s and other localities’ emission requirements as shipped from factory.
	O.	Special Features Available:
	1.	Coil Options
Base unit with tin plated indoor coil hairpins available as a factory installed option.
	2.	Compressor Start Kit (single phase units only):
Shall provide additional starting torque for single-phase compressors.
	3.	Thermostat:
To provide for one-stage heating and cooling in addition manual or automatic changeover and indoor fan control.
	4.	Crankcase Heater:
Shall provide anti-floodback protection for low-load cooling applications.
	5.	Economizer:
(Horizontal - Field installed accessory)
(Vertical - Field installed accessory)
	a.	Economizer controls capable of providing free cooling using outside air.
	b.	Equipped with low leakage dampers not to exceed 3% leakage, at 1.0 IN. W.C. pressure differential.
	c.	Spring return motor shuts off outdoor damper on power failure.
	6.	Filter Rack Kit:
Shall provide filter mounting for downflow applications. Offered as field installed accessory.
	7.	Flat Roof Curb:
Curbs shall have seal strip and a wood nailer for flashing and shall be installed per manufacturer’s instructions.
	8.	Flue Discharge Deflector
Directs flue gas exhaust; 90 degrees upward from current discharge.
	9.	Heat Exchanger
Stainless Steel Heat Exchanger available as a factory installed option.
	10.	High Altitude Propane Conversion Kit:
Shall consist of all required hardware to convert to propane gas heat operation at 2001 to 6000 ft (611 to 1829 m) above sea level.
	11.	Low Ambient Package:
Shall consist of a solid-state control and condenser coil temperature sensor for controlling condenser-fan motor operation, which shall allow unit to operate down to 0_F (-18_C) outdoor ambient temperature when properly installed.
	12.	Manual Outdoor Air Damper:
Package shall consist of damper, birdscreen, and rainhood which can be preset to admit outdoor air for year-round ventilation.
	13.	Natural-to-Propane Conversion Kit:
Shall be complete with all required hardware to convert to  propane gas operation at 10.0 IN. W.C. manifold pressure.
	14.	Propane-to-Natural Conversion Kit
Shall be complete with all hardware to convert to natural gas at standard altitude (0 to 2000 ft [0 to 610 m] above sea level).
	15.	Square-To-Round Duct Transitions (24-48 models):
Shall have the ability to convert the supply and return openings from rectangular to round.
	16.	Time Guard II
Automatically prevents the compressor from restarting for at least 4 minutes and 45 seconds after shutdown of the compressor. Not required when a corporate programmable thermostat is applied or with a RTU-MP control. Offered as a field installed accessory.
	17.	Low Cabinet Air Leakage
Cabinet air leakage less than 2.0% at 1.0 in. W.C. and cabinet air leakage less than 1.4% at 0.5 in. W.C., when tested in accordance with ASHRAE standard 193. Available as a factory installed option.
	18.	Louver Metal  Outdoor Coil Grille
Shall provide hail and vandalism protection. Available as a field installed accessory.
	19.	Low Pressure Switch Kit
Kit is designed for use when a low pressure control is desired. This kit provides added reliability for the compressor.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

E2016 Bryant Heating & Cooling Systems D 7310 W. Morris St. D Indianapolis, IN  46231                        Edition Date: 10/16

Replaces:  GS-PDS577C-10

Catalog No.  GS-PDS577C-11