Siemens 184-115 Restrictor Tee Red Barb Type 2,
Restrictors are available in a variety of orifice sizes and
connection types.
Applications
External restrictors are use:
● For 1-pipe room thermostats, 20 scim (5.5 ml/s),
refer to Figure 3.
● For 1-pipe transmitters, 40 scim (11 ml/s), refer to
Figures 1 and 2.
● When installed tubing lengths exceed maximum
recommended values, refer to Figure 2.
● With check valves to provide air flow time delays: – Slow to supply, fast to exhaust, refer to Figure 4. – Fast to supply, slow to exhaust, refer to Figure 5.
● VAV vortex control. Use 80 scim (22 ml/s) restrictor
in positioning relay control pressure line to
prevent cycling.
● When other air capacities, 10 scim (2.7 ml/s),
or 320 scim (87 ml/s) are required to compensate for
tubing size or response time.

