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Motorized Butterfly Valves for HVAC Systems
Date:2026-05-25 11:18:13 Author:Zhejiang Kinko Fluid Equipment Co., Ltd

Why Motorized Butterfly Valves for HVAC?

Unlike manual valves, motorized variants allow for modulating control or on/off actuation via a 0-10V or 4-20mA signal. Key benefits include:

  • Energy Efficiency: Low pressure drop reduces pump energy consumption.

  • Fast Response: 90-degree rotation allows for quick shut-off.

  • Bidirectional Sealing: Reliable isolation under high pressure differentials (PN16/PN25).


Technical Specifications

ParameterSpecification
Size RangeDN50 to DN600 (2” to 24”)
Body MaterialDuctile Iron / Stainless Steel 304
Disc MaterialEpoxy-coated Nodular Iron / Stainless Steel
Seat MaterialEPDM / Viton / PTFE
End ConnectionWafer Type
Actuator TypeOn/Off or Modulating
Control Signal0-10V, 4-20mA, or 2-point floating
Close-off PressureMax 16 Bar (232 PSI)
Ambient Temp-10°C to +60°C (14°F to 140°F)

Flow Coefficient (Cv) vs. Pressure Drop

For HVAC water systems, aim for a pressure drop (ΔP) of 0.5 to 2 PSI at maximum flow.

Valve Size (DN)InchesMax CvRecommended Torque (Nm)
DN502"11015 Nm
DN652.5"18020 Nm
DN803"28025 Nm
DN1004"45035 Nm
DN1506"110060 Nm
DN2008"2100100 Nm

Tip: For modulating service, avoid oversizing the valve. The valve should create 60-80% of the circuit’s total pressure drop at full load.



Actuator Selection Guide

HVAC ApplicationMax Valve SizeRequired TorqueActuator SpeedSignal Type
AHU Chilled Water CoilDN15060 Nm35 sec0-10V
Cooling Tower BypassDN200100 Nm15 secOn/Off
Chiller IsolationDN250200 Nm45 sec4-20mA
Heat Pump LoopDN10035 Nm30 sec0-10V

Torque Calculation Formula

Required Torque (Nm) = (Pressure Differential in Bar) x (DN in mm) / 20

*Example: DN150 at 5 Bar differential → (5 x 150) / 20 = 37.5 Nm. Select 60 Nm actuator for a 1.5x safety factor.*


Installation Best Practices

  1. Upstream Piping: Allow 5x pipe diameter of straight run before the valve.

  2. Disc Position: Keep the disc slightly open (10°) during flange welding to prevent gasket damage.

  3. Actuator Mounting: Avoid mounting the actuator upside down unless rated IP67 to prevent condensation damage.

  4. Manual Override: Always test manual operation before powering up.


Ivan (Mobile:+86-18968769287)
          WhatsApp:+86-13579991606

Wechat:+86-18968769287

Website:www.kinko-flow.com
ZHEJIANG KINKO FLUID EQUIPMENT CO.,LTD


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