Carrier 37HS specifications System-Powered Controls with Pneumatic Interface

Page 69

System-Powered Controls with Pneumatic Interface

PNEUMATIC SEQUENCED HEATING/COOLING (HOT WATER) Ð By using a 20 psi pneumatic source, one ther- mostat can control both heating and Moduline cooling in the conditioned space. The pneumatic circuit is interfaced with the system-powered circuit by use of a pilot valve. In cool- ing, the Moduline air¯ow is controlled by the duct-powered volume controller just as in all system-powered control. As the schematic diagram shows, a DA pneumatic wall ther- mostat working through the pilot valve, replacing the system- powered thermostat, modulates the pilot valve and thus the volume controller low side pressure.

Figure 75 shows the piping diagram. Figure 76 shows the sequence diagram for a direct acting thermostat with a nor- mally open pilot valve. With the system shut down and the space temperature low, at start-up the thermostat branch pres- sure is low, and the normally open water valve (or other heat- ing means) is open. As the space temperature rises, the branch pressure rises, modulating the water valve to a closed po- sition. The pilot valve is normally open, with set point above water valve spring rate, thus maintaining a low pressure in the low side of the volume controller, closing the bleed valve in the controller and raising the bellows pressure to the duct pressure level; this results in unit shutoff.

If the space temperature continues to rise, the NO pilot valve will modulate toward closed, raising the low side pres- sure, opening the bleed, reducing the bellows pressure, and opening the Moduline unit air valve. The air¯ow will rise until the volume controller setting is reached.

Note that the spring rates of the hot water valve and the pilot valve must be properly matched to accomplish the ac- tion described above.

A heating/cooling sequence can also be accomplished with a reverse acting circuit (Fig. 77 and 78). At start-up, the tem- perature is low, the branch pressure is high, and normally closed water valve is wide open. As the space temperature rises, the branch pressure falls and the water valve closes, stopping the heating supply. The pilot valve is NC and thus at branch pressures above its setting will open, volume con- troller low pressure will be reduced, the bellows pressure will rise and the unit will shut off.

LEGEND FOR FIG. 75 - 78

DA

Ð Direct Acting

NC Ð Normally Closed

HW

Ð Hot Water

NO Ð Normally Open

M

Ð Main

RA Ð Reverse Acting

Fig. 75 Ð Piping Diagram, Heating/Cooling

Sequence, DA Thermostat

Fig. 76 Ð Sequence Diagram Ð DA Thermostat

Fig. 77 Ð Piping Diagram, Heating/Cooling

Sequence, RA Thermostat

Fig. 78 Ð Sequence Diagram, RA Thermostat

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Contents Introduction Contents37HS Unit With VAV Controls Building Load CalculationEstimating Block Load Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page 35BD Heating Slot Boot Diffuser Director Diffuser Terminal Selection Layout Optimum Outlet DischargeLocation Guidelines Single Moduline Unit Connected to Supply Duct Diffuser Locations for Preferred 2-Way or One-Way Blow Recommended Maximum Cfm Per TerminalAir Throw Data Ð Way and 1-Way Director, 3-Slot Diffusers Consider Unit Combinations And Run Run-Out Duct for Single Moduline Unit 37HS1 Units in Air Series 37HS1 Units in Air Series 37HS2 Units in Air Series 37HS2 Units in Air Series 37HS4 Units in Air Series 37HS4 Units in Air Series Air Series of Units with Different Capacities Air Series of Units of the Same Size and Capacity Units in Adjoining Modules Additional DP for Flexible Duct with 90-Degree BendMaximum Number of Units in an Air Series on One Controller Flexible Duct Used with 90-Degree BendLocation of Volume Controller On Single Unit Incorrect Layout of Moduline Units with Controls Corrected Layout Shows the internal components of the Moduline unit Moduline ValveBellows and Unit Air Valve Arrangement Cross Section of 37HS Moduline Air Terminal High and Low Pressure Pick-Up Tubes Control Applications37HS Control Components Wall-Mounted Thermostat Constant Volume Control Arrangement Cooling/Heating Wall Thermostat VAV Control Arrangement with Electric Heat Interlock Control Index Control Selection37HS Control Combinations Heating & Cooling Electric Changeover HEATING/COOLING Control Operating Sequences Variable Volume Controls Schematic Page Page Page Location of CV Unit for Warm-Up Application Page Page Page System-Powered Controls with Electric Interface Page Page Page Connection for Electric Interlock System-Powered Controls with Pneumatic Interface Piping Diagram, no Conguration Pneumatic Warm-Up Maximum Air¯ow Settings Airflow AdjustmentMultiple Unit Air¯ow Variation HK08ZZ030Moduline Diffuser Mixing Room Air and Primary Air AIR DistributionTypical Room Air Distribution Pattern Slot Openings in Standard and Optional Diffusers Standard Diffusers for 37HS1 Standard Diffusers for 37HS2 Standard Diffusers for 37HS4 Model Type Optional Diffusers for 37HS1Optional Diffusers for 37HS2 Optional Diffusers for 37HS4 Air Throw Data Ð Way and 2-Way Blow, 2-Slot Diffusers Page Copyright 1991 Carrier Corporation

37HS specifications

The Carrier 37HS is a cutting-edge heating, ventilation, and air conditioning (HVAC) solution designed to deliver exceptional performance and energy efficiency for residential and commercial applications. This unit is particularly favored for its advanced features and reliable operation, making it a popular choice among homeowners and building managers alike.

One of the standout characteristics of the Carrier 37HS is its high Seasonal Energy Efficiency Ratio (SEER), which indicates its ability to provide effective cooling while minimizing energy consumption. This makes it not only cost-effective but also an environmentally-friendly choice, helping to reduce the overall carbon footprint. The unit is equipped with state-of-the-art inverter technology, which allows it to adjust its cooling capacity to match the current demand, thus enhancing comfort while optimizing energy use.

The Carrier 37HS incorporates a high-efficiency scroll compressor that operates quietly and efficiently. This technology enhances the unit's reliability and longer service life while ensuring minimal noise levels during operation, making it suitable for residential settings where tranquility is paramount.

A significant feature of the 37HS is its variable-speed fan system, which enables gradual adjustments in airflow to maintain a consistent and comfortable indoor environment. This not only contributes to enhanced comfort but also reduces wear and tear on the system, further extending its longevity.

Moreover, the Carrier 37HS is designed with advanced air filtration capabilities, utilizing multi-stage filters that capture airborne particles, allergens, and pollutants. This results in improved indoor air quality, making it an ideal choice for those with allergies or respiratory issues.

The unit also boasts user-friendly smart controls, allowing homeowners to monitor and adjust settings remotely via a smartphone app. This feature adds convenience and assists in energy management, ensuring that users can optimize their HVAC system even when they are away from home.

In summary, the Carrier 37HS stands out for its exceptional energy efficiency, quiet operation, advanced technology, superior air filtration, and modern smart controls. These features collectively make it a prime solution for those seeking a reliable HVAC system that delivers both comfort and savings, while also contributing positively to environmental sustainability. Whether for a residential setting or a commercial establishment, the Carrier 37HS is engineered to meet a variety of climate control needs with excellence.
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