Basic Documentation

Table Of Contents
Project Name 230900 - 5 BAS AND CONTROL FOR HVAC
Date
possible to manually limit the flow to the required value with the flow
limiter and then modulate the flow with the control valve and actuator.
a) A table shall be attached to each valve indicating GPM corresponding
to each setting on the dial.
b) No mechanical devices besides the valve and actuator shall be
permitted to adjust the maximum flow setting. Flow limiting port
shall be integrated into the valve body.
c) The valve shall always maintain full nominal stroke regardless of the
maximum flow setting of the flow limiter.
d) The flow limiter shall be lockable and tamper resistant when the
actuator is installed correctly.
7) At any given actuator setting the flow accuracy across the entire pressure
independent operating range of the automatic differential pressure regulator
shall be ±10% or less.
8) Pressure ports shall be standard in the body of the valve for all flanged
valves. Pressure ports shall provide a means for a balancer to test the
differential pressure across the valve control port to ensure the PICV is
operating within the pressure independent range.
9) Valves 2-1/2 inch and larger shall be provided with ANSI 125 or ANSI 250
flanged connections.
10) Valves 2-1/2 inch and larger line size shall meet or exceed ANSI Class IV
(0 to 0.01% of nominal maximum) leakage rating at 100 psi close off.
11) The differential pressure range for effective pressure independent operation
shall be 3.6 – 90 psi or 8 – 90 psi for 2-½ and 3 inch flanged valves
depending on the maximum gpm flow range of the valve.
12) Valve materials shall meet or exceed the following:
a) Valve body: Cast iron
b) Stem, spring: Stainless steel
c) Seat: Stainless steel
d) Plug: Brass and EPDM
e) Seals: EPDM (peroxide cured)
6. Threaded Valves, line size ½” to 2”
a. Controlled Media Specific Items
1) The control valve shall be suitable for chilled water to a minimum of 35°F
(2°C) and hot water to a maximum temperature of 250°F (121°C).
2) The control valve shall be suitable for up to 50% ethylene or propylene
glycol solutions, chilled glycol/water solutions to a minimum of 35°F (2°C)
and hot glycol/water solutions to a maximum temperature of 250°F (121°C).
b. General Construction Materials/Applicable Standards
1) Control valve bodies shall be constructed of forged DZR brass and shall
meet requirements of ANSI 250 pressure class.
2) Inlets and outlets shall be clearly marked on the valve bodies.
3) Valves shall be constructed with a single chamber and multiple seats to
provide flow limiting, pressure compensation and flow control.
4) Valves shall contain a mechanical, spring-loaded pressure independent
regulator to maintain a consistent differential pressure across the control
port of the valve.
5) Valves shall contain an actuated flow control portion that responds to the
modulating signal from the controller. This control valve portion shall have
a linear flow characteristic.