251934-YTG-G-0708

BAS Ready Economizer (2-10 V.D.C. Actuator Without a Controller)

Hinged Filter Door Access And Tool Free Access Panels

Hinged Tool Free Blower, Blower Motor, Filter And Electrical Access Panels

High Static Drive

Low Static Drive (ZJ/ZR/ZF300 only)

2" Pleated Filters

4" Throw Away Filters

Disconnect Switch

Supply Air Smoke Detector

Return Air Smoke Detector

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 Reheat Control Board.) Each mode is described below. Refer to Reheat Controls - Part 1 and Part 2 when reading this section.

“Normal” Mode

When the reheat control board (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 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). The Y1 signal is passed to the unit control board (UCB), which engages circuit # 1, resulting in circuit #1 reheat mode operation.

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, resulting 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 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 a call for dehumidification 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. 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" & "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 dehumidification 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.

12

Johnson Controls Unitary Products

Page 12
Image 12
York R-410A manual Reheat Mode Sequence Of Operation, Normal Mode, Alternate Mode

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.