BREWHA Equipment Co Ltd. BIAC, User Manual

Page: 9 / 58

Use of a pressure and vacuum relief valve to prevent pressure build up
A vacuum breaker and pressure relief valve installed on a fermenter
lid port is a necessary accessory to help insure against damage to
a fermenter (and possible injury) caused by pressure or vacuum. A
vacuum, caused by a cooling of liquid or gas inside the fermenter
can pull the sides in, and pressure building up from expansion or
gas produced during fermentation can push the walls out. In either
situation, the fermenter can be damaged, possibly beyond repair.
The BREWHA Vacuum Breaker and Pressure Relief valve serves
to protect your investment by opening when either 25mmHg of
vacuum or 3psig of pressure occurs in the 3-in-1 fermenter (14.9psig
in the 4-in-1 fermenters).
When a vacuum builds up, it pulls down on the valve, opening the
valve and letting air into the fermenter. When pressure
builds up, the relief valve is pushed open, letting gas escape.
It is important to note that a safety relief valve should always
be used in ADDITION to a blow off hose or air lock, and never be used as the primary means
for release of gas; the reason, is that in the event where a fermenter was overfilled (and/or
fermentation too vigorous) krausen (foam) could enter the opening mechanism and prevent the
valve from operating properly and this is more likely to occur if used for primary gas relief.
8
BIAC User Manual Safety
Warning: Never use the pressure relief valve as primary means of gas relief;
always use a large diameter blow-off hose for gas release and the relief valve as
a safety backup.
Figure 4