Four-pipe hydronic heating/cooling unit | Trane Zone Controller

Chapter 4 Input/output functions and wiring for typical applications

Figure 10. Four-pipe hydronic heating/cooling unit

Fan status (closed=on)*

Occupancy (open=occupied)*

Condensate overflow (closed=normal)*

Low-coil-temperature detection (open=normal)*

24 Vac H N

24 V†

Fan, high speed

24 V†

Exhaust (or fan, medium speed)

24 V†

Fan, low speed

24 V† Cooling valve

			24 V†
			Heating valve
				24 V†
				Outdoor air damper actuator
	Open Close	Open Close	Open Close	24 V†
	Open Close	Open Close	Open Close	Generic/baseboard heat
				Generic/baseboard heat

Entering water LonTalk temperature

Discharge air temperature

	AI4 input: See	LonTalk
	AI4 input: See	in
	Figures 5 and 6	in
	Figures 5 and 6
	on page 20 for
	wiring options	out
		out

Outdoor air or generic temperature

* All binary inputs are configurable.

†Connect 24 V to an AC POWER (24V) terminal.

26	CNT-SVX07C-EN

Image 36

Trane Zone Controller, N512, CNT-SVX07C-EN manual Four-pipe hydronic heating/cooling unit

Contents

Installation and Operation Tracer ZN521 Zone Controller Page CNT-SVX07C-EN April CNT-SVX07C-EN Tracer ZN521 Zone Controller Installation and Operation CNT-SVX07C-EN Contents Sequence of operations Status indicators for operation and communication Troubleshooting Index Overview and specifications Product description Dimensions Storage environmentClearances Plastic-cover model dimensions and clearances Agency listing/compliance Additional components Tracer zone temperature sensor options Damper actuatorsZone humidity sensor CO2 sensor Overview and specifications Input/output terminal wiring AC-power wiring General wiring information Communication-link wiring and addressing General wiring information Location recommendations Operating environment requirements Mounting recommendations Mounting the Tracer ZN521 zone controller Typical applications for the Tracer ZN521 zone controller Application SpeedfanMultiple DehumidificationControlValve Economizing HeatElectric BI1 Low-coil-temperature detection Binary inputsBI2 Condensate overflow Binary inputs BI3 Occupancy or generic binary input BI4 Fan status ZN Zone temperature Analog inputsGND Ground terminals Analog inputs FAN Fan mode input AI1 Entering water temperatureSET Local setpoint AI2 Discharge air temperature AI3 Outdoor air temperature or generic temperature AI4 configuration options and associated measurement ranges Configuration Measurement rangeAI4 Universal 4-20 mA AI4 terminal wiring CO2 measurement Binary outputs Generic binary outputBinary output functions Binary output Functions Wiring requirements and options Overriding binary outputsRequired controller inputs for proper operation Function Input source For more information See Two-pipe hydronic-cooling unit Two-pipe hydronic-heating unit Two-pipe hydronic heating/cooling unit with auto changeover Four-pipe hydronic heating/cooling unit Four-pipe heating/cooling unit with auto changeover Two-pipe heating unit with DX cooling Electric heat unit with DX cooling Electric heat unit Two-pipe heating unit with face-and-bypass damper Two-pipe heating/cooling unit with face-and-bypass damper Four-pipe heating/cooling unit with face-and-bypass damper Input/output functions and wiring for typical applications Power-up sequence Random start Occupied mode Unoccupied modeOccupied standby mode Occupancy modes Occupied bypass mode Timed override control Zone temperature control Cascade zone controlSimplified zone control Heating or cooling mode Discharge air temperingMorning warm-up Morning cool-down Entering water temperature sampling function Fan operation Exhaust control Exhaust control Valve operation Modulating valve operationModulating valve calibration Valve control options Modulating outdoor/return air dampers Two-position valve operationIsolation-valve operation Two-pipe operation Modulating outdoor air damper position Ashrae Cycle 1 conformance Ashrae Cycle 2 conformanceEconomizing free cooling Two-position control of a modulating outdoor air damper Face-and-bypass damper operationDX cooling operation Face-and-bypass, isolation-valve operation Electric heat operation Baseboard heat operationDehumidification Peer-to-peer communication Unit protection strategies Smart reset Low-coil-temperature protectionFan off delay Condensate overflow Filter-maintenance timer Freeze protection discharge air temperature low limitFreeze avoidance Test button Tracer ZN521 zone controller circuit board Manual output test For non Output Close damper, air Outdoor Open damper, air Outdoor Step Result BOP1 BOP2 BOP3 BOP4 BOP5 BOP6 BOP7 BOP8 BOP9 Service pin button Red LED Service indicatorInterpreting LEDs LED activity Explanation Green LED Status indicator Yellow LED Communications indicator Diagnostics Types of diagnostics Table of diagnostics DiagnosticsDiagnostic Probable cause Consequences Type Fan unaffected Valved unaffected Position Damper unaffected Status indicators for operation and communication Fan does not energize Probable cause Explanation Troubleshooting Valves remain closed Valves remain open DX or electric heat does not energize Outdoor air damper remains closed Outdoor air damper remains open Outdoor air damper remains open Troubleshooting Index Numerics Index Index Index Page Trane