
INSTRUCTION MANUAL 
HS-232 
REVISION C
Hoffman Specialty
®
Series I 
In-line Float and Thermostatic 
Steam Traps
CAUTION
WARNING
• Before using product, read and understand instructions.
• Save these instructions for future reference.
• All work must be performed by qualified personnel trained in the proper application, 
installation, and maintenance of steam systems in accordance with all applicable codes 
and ordinances.
WARNING
!
®
• To prevent serious burns, wear heat resistant gloves when opening and closing steam 
valves, or handling hot equipment.
• To prevent serious burns, the internal pressure of the trap must be 0 psi (0 bar) before 
servicing.
• To prevent serious personal injury from steam pipe blow down, connect a temporary 
pipe between the steam pipe opening and a drain, or stand at least 100 ft. (30m) from 
the front of the pipe opening.
• To prevent property damage, personal injury, or death, cap off the gate valves if they 
are not connected to a drain and when they are not in use for test or pressure relief.
Failure to follow this warning could cause property damage, personal injury or death.
IMPORTANT: To prevent system damage from water 
hammer or sudden shock, open supply valves slowly.
If you are uncertain about the product’s adaptability for 
your application, please call the factory or authorized 
representative before using the product.
The trap seat rating (stamped on the nameplate) must 
be equal to or greater than the maximum pressure differential across the trap.

2
The balanced pressure thermostatic element is 
open to vent air from the steam space into the 
return line.
The balanced pressure thermostatic element 
is closed to prevent the loss of steam into the 
return line.
The float will modulate to provide continuous 
drainage of condensate.
OPERATION
START-UP
NORMAL OPERATION

3
INSTALLATION –
Series I In-line Float and Thermostatic Steam Traps
TYPICAL PIPING DIAGRAMS
Trap Draining to Open Drain
Trap Draining to Gravity Return Line
Trap Draining to Overhead Return Line 
or Pressurized Return Line
1. Determine where to install the trap, 
based on the following requirements:
a. The trap must be located as close 
as possible and below the equipment 
to be drained.
b. The trap must be in a straight run
of horizontal pipe and pitched to 
allow condensate to flow into the 
trap inlet and away from the 
trap outlet. Refer to the Typical 
Piping Diagrams at the right.
c. Plenty of space around the trap is
needed for servicing, which may 
include removal of the body or cover.
2. Install a shut-off valve (A) on the inlet pipe (B).

3. Install a Y Strainer (C) on
the inlet pipe (B).
6. Close the gate valve (D). If it is not connected 
to a drain, install a cap (E) on the outlet pipe (F). 
Note: Remove the cap (E) when the gate valve 
(D) is used for test or pressure relief. Recap when 
the test or pressure relief is complete.
5a. Cap off the outlet pipe (X).
b. Slowly turn steam on with full pressure for 
(5) five minutes to blowdown the inlet pipe (B).
c. Turn off steam and allow pipe to cool.
d. Remove cap from the outlet pipe (X).
To prevent serious personal injury 
from steam pipe blow down, connect 
a temporary pipe between the steam 
pipe opening and a drain, or stand 
at least 100 ft. (30m) from the front 
of the pipe opening.
Failure to follow this warning 
could cause property damage, 
personal injury, or death.
WARNING
To prevent serious burns, the internal 
pressure of the trap must be 0 psi (0 
bar) before servicing.
Failure to follow this caution will cause 
personal injury.
CAUTION
4. Install a gate valve for blow down (D) by con-
necting it to the Y Strainer drain tapping (C).
To prevent property damage, personal injury, or death, cap off the gate valve if it is 
not connected to a drain and when it is not in use for test or pressure relief.
Failure to follow this warning could cause property damage, personal injury, or death.

5
7. Install a pipe union (G) on the inlet pipe (B).
8. Position the F&T trap so that the inlet pipe (B) 
will connect with the “IN” tapping on the body (H), 
and the “DOWN” arrow (J) is pointing down.
9. Install the F&T trap (K) on the inlet pipe (B) 
as positioned in Step 8.
10. Install a tee fitting (L) on the return line (M) 
near the trap outlet (N).
For Applications with a Return Line
11a. Install a gate valve (P) on the outlet pipe (Q)
for test or pressure relief.
b. Close the gate valve (P).

12. If the gate valve (P) is not connected to a 
drain, install a cap (R) on the outlet pipe (Q). 
Note: Remove the cap (R) when the gate 
valve (P) is used for test or pressure relief. 
Recap when the test or pressure relief is 
complete.
13. Install a check valve (S) on the return line (M).
14. Install a shut-off valve (T) on the return line (M).
For Applications with a Gravity Return, Pressurized Return or 
Return Line Above the Trap Discharge
For All Series Applications
To prevent property damage, personal injury, or death, cap off the gate valve if it is 
not connected to a drain, and when it is not in use for test or pressure relief.
Failure to follow this warning could cause property damage, personal injury, or death.

7
15. Depending on your application, complete one 
of the following steps:
a. Connect the return line (M) to a drain (U)
OR
b. Add a gravity return line (V)
OR
c. Add a pressurized return (W) or a return line 
above the trap discharge (X).
INSTALLATION COMPLETE
MAINTENANCE
When checked regularly and properly maintained, the 
Series I Float and Thermostatic Traps will provide optimum performance and long life.
SCHEDULE:
• Initially, every 2-3 days after start-up until 
system is clean.
• Every 6 months thereafter.
PROCEDURE:
• To prevent serious burns, the internal pressure of the trap must be 0 psi (0 bar) 
before servicing.
• To prevent serious personal injury from steam pipe blow down, connect a temporary 
pipe between the steam pipe opening and a drain, or stand at least 100 ft. (30m) from 
the front of the pipe opening.
Failure to follow this caution will cause personal injury.
CAUTION
1.Inspect joints for leaks. Stop all leaks by tightening 
bolts and replacing gaskets, if necessary.
2.Clean strainers by opening the blow down valve and 
allowing full steam pressure to flow out for (2) two 
minutes. Then, close the valve.
3.Test traps by following the “Troubleshooting” 
procedure.

TROUBLESHOOTING
We recommend trap replacement when parts no 
longer operate properly. A new trap or a complete
cover assembly is more economical than repairing or 
replacing individual parts, and it will provide greater 
Problem:
1. Improper Heating
a. Cause: The float assembly is not opening or
functioning properly. This could be 
caused by a leak in the float.
Test: Use a thermometer to test inlet tem-
perature. A cold trap is an indication 
the trap failed closed.
Solution: Disassemble the trap. Shake the float,
listening for water, and inspect for leaks. 
Replace any worn or defective parts.
b. Cause: The steam pressure is higher than
the trap’s seat rating pressure which 
prevents the trap from opening.
Test: Check the seat pressure rating on the
In-line F&T trap nameplate with the 
available steam pressure to the 
equipment being drained.
Solution: Install a new Hoffman Specialty Bear
®
Tra p
with the proper pressure range. 
Note: The trap must be selected for 
the maximum differential pressure that 
will be encountered. A high pressure 
seat may be used at lower differential 
pressures, but the capacity rating will 
be less than an identical size trap with 
a low pressure rated seat.
reliability. If you choose to repair the trap, order 
Hoffman Specialty replacement parts and follow the 
Repair Procedure provided.
Problem:
2. Energy Wasted
a. Cause: A worn pin and seat, or dirt deposited
on the seat prevents tight closure.
Test: Using a stethoscope, listen for a low
pitch whistle sound. A low pitch whistle sound indicates the trap is open 
and blowing live steam.
Solution: Disassemble the trap and inspect for
dirt or worn parts. Clean if dirty, or 
replace if worn.
b. Cause: The thermostatic element failed open
and is blowing live steam.
Test: Using a stethoscope, listen for a low
pitch whistle sound. A low pitch whistle sound indicates the trap is open 
and blowing live steam.
Solution: Disassemble the trap and replace the 
thermostatic element
c. Cause: Full capacity drainage is prevented
by worn linkage.
Test: Disassemble the trap and inspect for
worn parts.
Solution: Install a new Hoffman Specialty In-
line F&T Bear Trap
®
.
Xylem Inc.
8200 N. Austin Avenue 
Morton Grove, Illinois 60053 
Phone: (847) 966-3700 
Fax: (847) 965-8379 
www.xyleminc.com/brands/bellgossett
Bell & Gossett is a trademark of Xylem Inc. or one of its subsidiaries. 
© 2012 Xylem Inc. HS-232C October 2012 Part No. 510987