Honeywell MS8105A1130 - User Manual

PRODUCT DATA
38-00032-01
Global Field Devices
VRN Pressure Independent Control
Valves and Actuators
APPLICATION
The VRN2 two-way pressure independent control valves
maintain constant flow of hot or chilled water with glycol
solutions up to 50% in closed-loop heating, ventilating,
and air conditioning (HVAC Division 23) systems
regardless of head pressure fluctuations above the
minimum specified pressure drop. These valve assemblies
can be used with Honeywell non-spring return or spring
return direct coupled actuators (DCA).
The built-in differential pressure regulator makes fluid
flow through the valve independent of changes in supply
pressure, eliminating “hunting” by the control system,
even at low coil flow. The pressure regulator virtually
eliminates cavitation in the valve, and decouples the
control valve from the effects of piping components such
as reducers and elbows.
Pressure independent control valves are sized to match
design coil flow regardless of coil size. VRN2 valves
eliminate the need to balance the system for proper flow,
and allow chillers to be operated at design temperature
differential for maximum efficiency at every load
condition. When used in a system with variable speed
pump drives, 3-way valves and coil bypass lines are not
required. In new construction, VRN2 valves perform better
than reverse return piping designs without the extra
materials these systems need.
Pressure-independent control requires less flow, enabling
use of smaller piping, pumps, and chillers.
FEATURES
• Sizes from 1/2 to 3 in. with internal (female) NPT
connections.
• Controls hot or chilled water with up to 50% glycol.
• Regulated flow rates available from 1 to 95 gpm.
• Differential pressure regulator for constant pressure
drop across valve seat.
• Positive pressure, rolling diaphragm regulator design
for flow control accuracy of ±5%.
• Equal percentage flow characteristic using patented
flow control ball insert.
• Multiple maximum flow rates available per valve size.
• Patented ball seals for low operating torque.
• Nickel-chrome plated brass or stainless steel trim.
• Choice of factory-installed actuation using
Honeywell MVN or MN/MS series direct coupled
actuators: Floating, Modulating (2-10 V), Non-Spring
Return and Spring Return.
• Spring return actuators field-configurable for
normally open or normally closed fail-safe position.
• Removable, manual operating handle to control
valve during installation or in an event of power
failure.
• Upstream Test Port for venting or pressure gauge
attachment.
• Three actuator orientations on the valve for cramped
spaces.
• Integral snubber eliminates effect of system
pressure fluctuations and entrapped air while
improving flow performance.
Contents
Application ..................................................................................... 1
Features .......................................................................................... 1
Specifications ............................................................................... 2
Ordering Information ................................................................ 2
Typical Specifications ............................................................... 12
Installation .................................................................................... 13
Operation and Checkout .......................................................... 18

Summary

Application of VRN2 Valves

Differential Pressure Regulator Function

Explains how the regulator eliminates cavitation and decouples the valve from piping effects.

VRN2 Valve Features

Actuator Compatibility

Mentions compatibility with Honeywell MVN or MN/MS series direct coupled actuators.

VRN Valve Specifications

MVN Actuator Specifications and Application

MVN Actuator Specifications

Covers type, stroke, fail-safe mode, torque, voltage, and environmental ratings.

Non-Spring Return Direct Coupled Actuator Details

Non-Spring Actuator Specifications

Covers type, stroke, fail-safe, torque, voltage, and environmental ratings.

Spring Return Direct Coupled Actuator

Spring Return Actuator Specifications

Covers type, stroke, fail-safe mode, torque, voltage, and environmental ratings.

Typical Specifications for VRN System

Valve Actuator Specification

Pressure Independent Valve Specification

Details valve housing, ball material, regulator design, and stem assembly.

VRN Valve Installation Guide

Installation Preparation

Mechanical Installation Procedures

Covers handling, sealing, torque, and mounting valve body.

Flow Direction and Stem Rotation

Details flow arrow orientation and stem rotation for two-way valves.

Electrical Installation and Wiring

Wiring for Fail-in-Place Actuators

Provides wiring diagrams for floating and modulating actuators that fail in place.

Wiring for Fail-Safe Actuators

Covers wiring for actuators with fail-safe operation, including end switches.

Operation and Checkout Procedures

Actuator Operation Verification

Describes cycling the actuator to verify rotation direction and control sequence.

Spring Return Actuator Fail-Safe Setting

Explains how to change spring return actuator orientation for fail-safe operation.

VRN2 Differential Pressure Operation

Settings and Adjustments for VRN Valves

Maximum Flow Trimming

Valve Service and Repair

In-line Valve Stem Replacement

Provides step-by-step instructions for replacing the valve stem in-line.

Honeywell MS8105A1130 Specifications

General

Brand	Honeywell
Model	MS8105A1130
Category	Controller
Language	English