12
Forbes Marshall Thermodynamic Trap
Note
: Never attempt to modify the product. When replacing part with new part, use the spare
parts listed in section 9.
Failure Mode
Possible Cause
Remedy
Motor-
boating
(chattering) of
disc.
Scratch on disc or body seat.
Check if scratch depth is less, then disc
and body seating faces flatness can be
improved by lapping individually on flat
surface or glass plate. If scratch depth is
more replace with new disc.
Note:
The total amount of metal from
body seat face removed should not
exceed 0.25mm (0.01”).
Disc or body seat is worn.
Replace with new disc. If body seat is
slightly worn it can be refaced by
lapping on flat surface or glass plate. If
body seat is worn more replace with
new steam trap.
Note:
The total
amount of metal from body seat face
removed should not exceed 0.25mm
(0.01”).
