Taylor-Wharton Freezing Tray - Manual

For 35HC, 35VHC, 36VHC
or 750RS Refrigerators
TW-51
HANDI-FREEZE
FREEZING TRAY
The Handi-Freeze tray provides an economical method of
freezing biologicals when a 35HC, 35VHC and 36VHC or
750RS Cryogenic Refrigerator is available. This acces-
sory replaces the necktube core of the four refrigerator
modules and allows the used to take advantage of the
cold nitrogen gas in the necktube for freezing purposes.
When materials is placed in the tray, the depth of the tray
may be adjusted by turning the knob on the top of the
unit. Clockwise rotation will move the tray upward toward
the warmer portion of the necktube; counter clockwise
rotation will move the tray deeper into the colder area.
SAFETY NOTICE – Do not attempt to use this accessory
until you read and understand the safety precautions for
cryogenic refrigerators that are found in Form TW-10
“Handle with Care”. The improper handling of cryogenic
fluids can cause personal injury.
Operation
The tray is designed to hold 24 vials, 12.5 mm in diameter or
less. The freezing rates involve many variables and must be
determined by the user from actual test data. In general, the
top tray position is used for temperature down to 0°F (-
18°C), the middle position to -50°F (-46°C), and the lower
position to cryogenic temperatures -200°F (-129°C).
Convenient index numbers on the freeze tray guide rods aid
in indexing freeze rates. The tray positioning control will
change the tray location by approximately ¼ in. (6.4 mm) for
each complete turn of the knob.
The necktube core of the refrigerator (35HC, 35VHC,
36VHC or 750RS) must be removed and the Handi-Freeze
tray can be inserted into the necktube. The canisters/racks,
if used, need not be removed, as the freeze tray design has
allowed clearance for the canister/rack handles.
Operating Tips
§ Frost formation may make operation of the mecha-
nism difficult. If the cold unit is exposed to moist air,
frost will form. If frost formation, makes the control
knob difficult to turn, remove the unit, and allow it to
warm-up, then dry the moisture with warm air or a dry
cloth.
§ Remove the Handi-Freeze tray from the refrigerator
when not in use. The unit is not insulated and its use
as a replacement for the insulated necktube core
provided with the refrigerator will result in much
greater liquid nitrogen consumption.
§ When removing the Handi-Freeze tray, use the
indentations on the cap. Do not use the tray position
control know as a handle or the unit may be dam-
aged.
§ The refrigerator should be at least half full of liquid
nitrogen.
§ A cooldown time of a least one day should be al-
lowed after filling a warm refrigerator. Allow one hour
after adding liquid refrigerant or after the addition of a
warm specimen canister/rack.