172-65391MA-08 (VS1A) 7 Oct 2021
10
Troubleshooting
NEVER apply direct heat to the float. The float may explode due to
increased internal pressure, causing accidents leading to serious injury
or damage to property and equipment.
WARNING
When disassembling or removing the product, wait until the internal
pressure equals atmospheric pressure and the surface of the product
has cooled to room temperature. Disassembling or removing the
product when it is hot or under pressure may lead to discharge of fluids,
causing burns, other injuries or damage.
CAUTION
When the product fails to operate properly, use the following table to locate the cause
and remedy.
Problem
Cause
Remedy
No initial air
discharged
(blocked)* or
discharge is
poor
Air is not reaching the vent because the
water in the piping is not being displaced by
air
Correct the inlet piping
(Inner diameter should be
at least 16 mm (
5
/
8
in))
The valve seat is clogged
Clean the valve seat
The inlet or outlet piping is clogged
Clean the piping and any
upstream strainer
Water leaks
when valve is
closed
Build-up on the surface of the valve seat or the
valve seat is damaged.
Clean or replace with a
new valve seat
The float is dirty or coated with a film, or is
deformed
Clean or replace with a
new float
Improper installation orientation
Correct the installation
Valve does
not close, and
water spurts
out
Water is inside the float
Replace with a new float
The guide plate is damaged
Replace with a new plate
Specific gravity of the liquid is not suitable for
this product
Select a product with
suitable specifications for
the operating conditions
*NOTE: Once the air vent closes, it will remain closed until internal pressure drops to near or
below atmospheric pressure. This condition may be confused with a malfunction
(blocked). If air is expected to accumulate in the piping during operation, use together
with an automatic air vent.
