Frequently Asked Questions
Which trap backs up more condensate, a Velan Bimetallic steam trap or a
thermodynamic steam trap?
Actual tests show that the thermodynamic
steam trap will back up
more condensate than a Velan bimetallic
steam trap. The reason
is because a thermodynamic steam trap discharges condensate based upon
ambient conditions, not by the amount condensate in the drain leg. If
it is warm outside, or the trap is insulated, it will not open and remove
condensate until the steam trapped above the disc condenses. Tests in
the Velan lab have shown that the thermodynamic
design can collect
up to 72 inches of condensate in a ¾” pipe before cycling. Conversely,
if a thermodynamic steam trap is exposed to low ambient temperatures,
or precipitation, it will cycle continuously, resulting in substantial
loss of live steam.
The Velan bimetallic steam trap will only hold a
maximum of 12-18 inches of water in a ¾” pipe in front of the trap. This will actually
promote better condensate removal because of the constant pressure drop across
the trap. In superheated conditions, the trap will remain fully closed
when no condensate is present.