Basic Documentation

Table Of Contents
Project Name 230900 - 6 BAS AND CONTROL FOR HVAC
Date
6) Valves shall contain a field adjustable flow limiter. The flow limiter shall
be easily adjustable in the field without the use of special tools. The
adjustment dial shall be set for and indicate maximum flow. It shall be
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) The dial shall show settings in GPM.
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 an optional accessory that can be added to threaded
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 inch and smaller shall be provided female NPT piping connections.
10) Close-off and leakage
a) Normally open valves ¾ inch and smaller line size shall meet or
exceed ANSI Class IV (0 to 0.01% of nominal maximum) leakage
rating at 200 psi close off.
b) Normally closed valves 1-1/4 inch and smaller line size shall meet or
exceed ANSI Class IV (0 to 0.01% of nominal maximum) leakage
rating at 45 psi close off.
c) Valves 1-1/2 and 2 inch line sizes shall meet or exceed ANSI Class
III (0 to 0.1% of nominal maximum) leakage rating at 50 psi close
off.
11) Differential pressure ranges:
a) The start-up differential pressure of the automatic differential
pressure regulator shall be between 2.3 and 4.6 psi, depending on
valve size and flow rate for ½ to 2 inch valves.
b) The maximum operating differential pressure of the automatic
differential pressure regulator shall be 58 psi for ½ to 2 inch valves.
c) In no instance shall the minimum effective pressure differential for
effective pressure independent operation exceed 4.6 psi for valves
less than or equal to 2 inch line size.
12) Valve materials shall meet or exceed the following:
a) Valve body: DZR brass
b) Stem, spring: Stainless steel
c) Seat: brass
d) Plug: Brass and EPDM
e) Seals: EPDM (peroxide cured)
E. Differential Pressure Control Valves :
1. Provide for constant speed pumping and modulating water flow systems to prevent
excessive pump pressure build-up. Provide a valve for each closed loop water system.
Valve shall be globe type.