York R-410A manual Reheat Mode Sequence of Operation

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246824-YTG-G-1208

•PROPANE CONVERSION KIT – Contains new orifices and gas valve springs to convert from natural to L.P. gas.

•60ºF GAS HEAT KIT – Provides an electric heat kit for the gas compartment for use in extreme low ambient conditions.

•ECONOMIZER (Downflow and Horizontal flow)

•POWER EXHAUST – (Unit mount – Downflow, Duct mount – Horizontal flow)

•DUAL ENTHALPY KIT - Provides a second input to economizer to monitor return air.

REHEAT MODE SEQUENCE OF OPERATION

The reheat control board allows the user to select two different modes of operation via a jumper connection on the board. (See Figure 3.) Each mode is described below.

“NORMAL” MODE

When the reheat control board (RCB) detects a need for dehu- midification (24VAC) at "HUM" via the field supplied dehumidis- tat connected to RHTB-1 and RHTB-2 and there is not a call for cooling, it energizes the hot gas relay (HGR), which energizes the 3-way valve (SOL 3), the condenser coil valve (SOL 2), and de-energizes the reheat coil bleed valve (SOL 1). (In the ZR150, SOL 2 is only energized when the discharge pressure in circuit #1 rises above 400 psig and de-energizes SOL 2 after the discharge pressure falls below 320 psig. Both outdoor fans of circuit #1 in the ZR150 also disengage to conserve energy.) The Y1 signal is passed to the unit control board (UCB), which engages circuit # 1, resulting in circuit #1 reheat mode opera- tion.

When the room thermostat calls for first stage cooling, with or without a call for dehumidification, the RCB senses a signal through "Y1", de-energizing the HGR, which de-energizes SOL 3 and SOL 2 and energizes SOL 1, engaging circuit #1, result- ing in circuit #1 cooling mode operation.

When the room thermostat calls for second stage cooling, the RCB senses a signal through "Y1" & "Y2" and engages circuit #1 and circuit #2 in cooling mode.

Indoor blower operation is initiated upon a call for first stage cooling, second stage cooling or dehumidification.

Anytime there is a call for 2 stages of cooling, the unit will not operate in the reheat mode, even if there is a call for dehumidi- fication at "HUM".

The unit will not operate in the reheat mode if there is any call for heating.

On units with economizers, the unit will not operate in the reheat mode if there is a call for cooling and the economizer is operating as first stage of cooling.

All safety devices function as previously described.

"ALTERNATE” MODE

When the RCB detects a need for dehumidification (24VAC) at "HUM" via the field supplied dehumidistat connected to RHTB-1 and RHTB-2, and there is not a call for cooling, it energizes the HGR, which energizes the SOL 3, SOL 2, and de-energizes SOL 1. (In the ZR150, SOL 2 is only energized when the dis- charge pressure in circuit #1 rises above 400 psig and de-ener- gizes SOL 2 after the discharge pressure falls below 320 psig. Both outdoor fans of circuit #1 in the ZR150 also disengage to conserve energy.) The unit then operates with circuit #1 in reheat mode and circuit #2 in cooling mode.

When the room thermostat calls for first stage cooling while there is still a call for dehumidification, no operational change is made. The call for cooling is ignored and the unit continues to operate with circuit #1 in reheat mode and circuit #2 in cooling mode.

When the room thermostat calls for second stage cooling, the RCB senses a signal through "Y1" and "Y2" and de-energizes the HGR, which de-energizes SOL 3 and SOL 2, and energizes SOL 1. Both circuits operate in the cooling mode.

Indoor blower operation is initiated upon a call for first stage cooling, second stage cooling or dehumidification.

Anytime there is a call for 2 stages of cooling, the unit will not operate in the reheat mode, even if there is still a call for dehu- midification at "HUM".

The unit will not operate in the reheat mode if there is any call for heating.

All safety devices function as previously described.

Johnson Controls Unitary Products

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Contents Technical Guide Component Location Table of ContentsHeat Pump Nomenclature Ton York Model Number NomenclatureStandard Features Features and BenefitsFactory Installed Options Control Options Field Installed Accessories Part Number Description AccessoriesGeneral Guide SpecificationsIndoor Evaporator FAN Assembly Electric Heating Section if Equipped Reheat Mode Sequence of Operation Reheat Control Board ZH078-150 Physical Data Physical DataFilters ZR078-150 Physical Data Reheat Coil Data XP078-150 Physical Data Min ZH/ZR/XP078-150 Unit LimitationsYTG-G-1208 ZH078-150 Cooling Capacities Capacity PerformanceZH078 6.5 Ton 115F ZH090 7.5 Ton ZH090 7.5 Ton ZH102 8.5 Ton ZH102 8.5 Ton ZH120 10 Ton 115F 125F ZH150 12.5 Ton ZH150 12.5 Ton ZR078 6.5 Ton Cooling ZR078-150 Cooling and Reheat Capacities115F 35F 45F ZR078 6.5 Ton ReheatCapacity Input ZR090 7.5 Ton Cooling 115F ZR090 7.5 Ton Reheat 75F 85F ZR102 8.5 Ton Cooling 115F ZR102 8.5 Ton Reheat 75F 85F ZR120 10 Ton Cooling 115F ZR120 10 Ton Reheat 75F 85F ZR150 12.5 Ton Cooling 115F 125F ZR150 12.5 Ton Reheat 75F 85F XP078 6.5 Ton XP078-150 Cooling Capacities115F 95F 105F XP090 7.5 Ton115F 125F XP102 8.5 Ton 115F XP120 10 Ton XP120 10 Ton XP150 12.5 Ton 115F 125F XP078-150 XP078-150 Heating CapacitiesCapacity Outdoor Temperature F @ 72% RH ZH078-150 Side Duct Application Airflow PerformanceZH078 6.5 Ton Side Duct ZH090 7.5 Ton Side DuctZH150 12.5 Ton Side Duct ZH120 10 Ton Side DuctZH078 6.5 Ton Bottom Duct ZH078-150 Bottom Duct ApplicationZH090 7.5 Ton Bottom Duct ZH102 8.5 Ton Bottom DuctZH150 12.5 Ton Bottom Duct ZH120 10 Ton Bottom DuctZR078 6.5 Ton Side Duct ZR078-150 Side Duct ApplicationZR090 7.5 Ton Side Duct ZR102 8.5 Ton Side DuctZR150 12.5 Ton Side Duct ZR120 10 Ton Side DuctZR078 6.5 Ton Bottom Duct ZR078-150 Bottom Duct ApplicationZR090 7.5 Ton Bottom Duct ZR102 8.5 Ton Bottom DuctZR150 12.5 Ton Bottom Duct ZR120 10 Ton Bottom DuctXP078 6.5 Ton Side Duct XP078-150 Side Duct ApplicationXP090 7.5 Ton Side Duct XP102 8.5 Ton Side DuctXP150 12.5 Ton Side Duct XP120 10 Ton Side DuctXP078 6.5 Ton Bottom Duct XP078-150 Bottom Duct ApplicationXP090 7.5 Ton Bottom Duct XP102 8.5 Ton Bottom DuctXP150 12.5 Ton Bottom Duct XP120 10 Ton Bottom DuctRPM Selection Tons Additional Static ResistanceDrive Selection Airflow PerformanceAir Temperature ºF Altitude/Temperature Correction FactorsFactor CorrectionPower Exhaust Specifications Indoor Blower SpecificationsGas Heat Minimum Supply Air Electric Heat Minimum Supply AirOutdoor Sound Power Levels ZH/ZR/XP078-150 Indoor Sound Power LevelsSound Performance Electric Heat MultipliersElectrical Data ZH078-150 Standard Motor Without Powered Convenience OutletZH078-150 Standard Motor Without Powered Convenience Outlet ZH078-150 Hi Static Motor Without Powered Convenience Outlet ZH078-150 Hi Static Motor Without Powered Convenience Outlet ZH078-150 Standard Motor With Powered Convenience Outlet ZH078-150 Standard Motor With Powered Convenience Outlet ZH078-150 Hi Static Motor With Powered Convenience Outlet ZH078-150 Hi Static Motor With Powered Convenience Outlet ZR078-150 Standard Motor Without Powered Convenience Outlet ZR078-150 Standard Motor Without Powered Convenience Outlet ZR078-150 Hi Static Motor Without Powered Convenience Outlet ZR078-150 Hi Static Motor Without Powered Convenience Outlet ZR078-150 Standard Motor With Powered Convenience Outlet ZR078-150 Standard Motor With Powered Convenience Outlet ZR078-150 Hi Static Motor With Powered Convenience Outlet ZR078-150 Hi Static Motor With Powered Convenience Outlet XP078-150 Standard Motor Without Powered Convenience Outlet XP078-150 Standard Motor Without Powered Convenience Outlet XP078-150 Hi Static Motor Without Powered Convenience Outlet Johnson Controls Unitary Products 101 XP078-150 Standard Motor With Powered Convenience Outlet Johnson Controls Unitary Products 103 XP078-150 Hi Static Motor With Powered Convenience Outlet Johnson Controls Unitary Products 105 ZH/ZR078-150 Typical Wiring Diagrams Typical Wiring DiagramsJohnson Controls Unitary Products 107 108 Johnson Controls Unitary Products Johnson Controls Unitary Products 109 110 Johnson Controls Unitary Products Johnson Controls Unitary Products 111 Typical ZR078-120 Reheat Wiring Diagram Typical ZR150 Reheat Wiring Diagram XP078-150 Typical Wiring Diagrams Johnson Controls Unitary Products 115 ZH/ZR/XP078-150 Unit Weights Weights and DimensionsUnit 4 Point Load Weight Unit 6 Point Load Weight ZH/ZR/XP078-150 Unit Accessory Weights ZH/ZR/XP078-150 Unit DimensionsZH/ZR/XP078-120 Detail a ZH/ZR/XP078-150 Unit Physical DimensionsZH/ZR/XP078-150 Unit Clearances ZH/ZR/XP078-150 Unit Bottom Duct OpeningsZH/ZR/XP078-120 Unit Side Duct Openings ZH/ZR/XP078-150 Unit Electrical EntryZH/ZR/XP150 Unit Side Duct Openings Side Duct DimensionsZH/ZR/XP078-150 Unit Left Duct Opening ZH/ZR/XP078-150 Roof Curb ZH/ZR/XP078-150 Unit Accessory DimensionsZH/ZR/XP078-150 Transition Roof Curb ZH/ZR/XP078-150 Economizer Assembly Field Installed Downflow Economizer W/Power Exhaust Factory Installed Downflow EconomizerEconomizer Options Economizer UsageSlab Economizer Downflow W/Power Exhaust Field Installed Horizontal Economizer W/Power ExhaustSlab Economizer End Return W/Power Exhaust 126 Johnson Controls Unitary Products YTG-G-1208 Johnson Controls Unitary Products 127 Johnson Controls Unitary Products York Drive Norman, OK
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R-410A specifications

York R-410A is a widely recognized and highly efficient refrigerant used in modern air conditioning systems. Developed as an environmentally friendly alternative to R-22, R-410A has gained popularity in the HVAC industry due to its numerous advantageous features and characteristics.

One of the main features of York R-410A is its ability to provide superior cooling performance. This refrigerant operates efficiently at both high and low temperatures, allowing systems using it to maintain optimal indoor climates even during extreme weather conditions. Its high energy efficiency ratio (EER) and seasonal energy efficiency ratio (SEER) ratings make it a preferred choice for energy-conscious consumers, resulting in lower energy bills and a reduced carbon footprint.

Technologically, York R-410A systems feature advanced compressor designs that enhance their overall reliability and performance. These compressors are often equipped with variable-speed technology, enabling them to adjust their output to match the cooling demands of the space. This not only improves comfort levels but also leads to efficient energy consumption, reducing wear and tear on the equipment over time.

Another significant characteristic of York R-410A is its non-ozone-depleting properties. Unlike its predecessor R-22, which is being phased out due to its damaging effects on the ozone layer, R-410A is designed to minimize environmental impact. Its lower global warming potential (GWP) further underscores its role in promoting sustainability within the HVAC sector.

Furthermore, York R-410A systems are engineered with enhanced safety features. The refrigerant is non-toxic and non-flammable, which makes it safer for use in both residential and commercial applications. Additionally, its high thermal stability reduces the risk of breakdown or leakage, contributing to longer system lifespans and lower maintenance costs.

In conclusion, York R-410A stands out as a cutting-edge refrigerant that combines efficiency, safety, and environmental responsibility. With its advanced technologies and remarkable characteristics, it meets the demands of modern air conditioning requirements while paving the way for a sustainable future in HVAC systems. Adopting York R-410A not only benefits individual users through improved comfort and lower energy bills but also plays a vital role in protecting our planet's ozone layer and mitigating climate change.
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