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REFRIGERANT STORAGE CYLINDER SAFETY
Check with your federal and/or state regulations on the proper vessel to store
refrigerant. In the USA DOT CFR 40 is required when filling and transporting refrigerant
storage vessels.
This unit is design to be used with 400 PSIG rated storage vessels. In the USA, this is
denoted by a DOT rating of 4ABA400 or 4BW400.
When recovering or filling a refrigerant storage vessel, never fill beyond 80% of its
water capacity (WC). Filling a tank at 70F to 90% and then putting it in a hot service van
will cause the liquid to expand until it becomes 100% full. The hydrostatic force of the
refrigerant could rupture the tank causing rapid venting or explosion. See illustration
in Diagram 1 below.
To calculate the maximum weight of a storage tank you will need to get two ratings
from the tank. One is WC (water capacity) and the other is TW (empty tank weight).
The maximum tank weight (MTW) is calculated as follows:
MTW=.8 x WC + TW
Turn on the scale and tare to Zero. Place storage tank on scale. Read the weight.
Compare that to the MTW calculated above. If the scale weight is below MTW,
you still
have
storage capacity you have in the tank. If the scale weight is above MTW, you have
a tank that is overfilled.
If an overfill condition does exist on a storage tank, place in a cool area and transfer
some of the refrigerant into another storage tank until the weight is below MTW.
Always use a calibrated scale to monitor the total weight of the tank when recovering
or filling refrigerant into a storage tank. Devices such as tank overfill floats should stop
the recovery unit, but do not stop the flow of refrigerant to the storage tank.
If the scale or an overfill device does detect tank full condition, the recovery unit should
be turned off and the storage tank valves closed.
80%
60 F˚
85%
90 F˚
90%
120 F˚
90%
60 F˚
95%
90 F˚
100%
Danger:
Tank Rupture
120 F˚
Filled to 80%
Capacity
Overfilled
to 90%
Capacity
Overfilled storage containers may
explode due to liquid refrigerant
expanding when heated.
Transportation of refrigerant
storage tanks more than 80%
full is a DOT violation.