Brochure
© 2015, Maxitrol Company. All Rights Reserved. © 2015 Maxitrol Company. All Rights Reserved.
DRAFT 09.18.2013
59
RUBBER SEAT POPPETS
For main burner and pilot load applications.
Example: To select an RV type regulator:
• Known: Single 150,000 Btu/h main burner; pipe size 1/2”; inlet pressure 7” w.c.; outlet pressure 4” w.c.
• Solution: The RV48 (1/2”) has a maximum capacity of 230,000 Bth/h and a maximum individual load of
160,000 Btu/h. The pressure drop at a ow rate of 150,000 Btu/h is 0.4” w.c., well below the available differential
of 3” w.c. The RV48 (without “L” xed orice) is the correct regulator to use for the application.
STRAIGHT-THRU-FLOW (S-T-F)
For main burner only applications not requiring a lockup type regulator. When sizing the S-T-F Series, it is recommended
that pressure drop not exceed 1/2 of available differential pressure.
Example: To select an RV type regulator:
• Known: Flow rate 2,000,000 Btu/h; pipe size 1 1/4”; inlet pressure 9” w.c.; outlet pressure 5” w.c.
• Solution: The RV81(1 1/4”) has a maximum capacity of 2,500,000 Btu/h. The pressure drop at a ow of
2,000,000 Btu/h is 0.66” w.c. The RV81 (1 1/4”) is the correct regulator to use with this application. The pressure
drop of the RV61 (1 1/4”) at a ow rate of 2,000,000 Btu/h is 2.64” w.c. This is within the available differential
but exceeds the recommended 50% maximum.
LEVER ACTING
For main burner and pilot load application requiring positive dead-end lockup (see Denitions page 63).
Example: To select a 325 Series regulator:
• Known: Single 145,000 Btu/h burner; pipe size 1/2”; inlet pressure 2 psi; outlet pressure 7” w.c.
• Solution: The 325-3’s pressure drop at a ow rate of 145,000 Btu/h is 7” w.c., well below the available
differential of 1 3/4 psi. The 325-3 (1/2”) is the correct regulator to use with this application.
BALANCED VALVE
For main burner and pilot load application requiring a lockup type regulator or zero governor usage (see Denitions page 63).
Example: To select a 210 or R/RS Series regulator:
• Known: Desired ow rate 6,000,000 Btu/h; pipe size 1 1/2”; inlet pressure 1 psi; outlet pressure 9” w.c.
• Solution: The 210E (1 1/2”) has a maximum capacity of 10,000,000 Btu/h. The 210D (1 1/2”) has a capacity of
6,000,000 Btu/h. Therefore, the 210E (1 1/2”) will give you the desired outlet pressure of 9” w.c. and is the
correct regulator to use for the application.
SIZING A REGULATOR
Sizing Examples