ULT Resource Library

Unrestricted airflow is critical for proper operation of a ULT.

• Filters and condensers should be regularly inspected for dirt and dust.
• Vacuum the condenser, filters can be vacuumed or washed in mild soap and water then air dried.

Provides energy efficient thermal barrier to keep cold air in and room temperature out. Good gasket seal helps insure product protection from ambient temperature and humidity migration to the interior, reduces frost build up on the inner doors and interior of the unit.

• Seals should be inspected regularly to check for any tears
• Inspect gaskets for deformity and pulling away from frame
• Frost and ice should be removed from around gaskets and between folds of gasket

*Do not use a sharp object that can puncture of dislodge the gasket.

Stay Ahead of Frost and Ice

• Formation of frost is unavoidable
• If not managed the frost will ultimately turn to ice
• Accumulation of ice on gaskets and sealing surfaces can prevent proper sealing
• Buildup of ice on interior walls will insulate the unit, reducing the cooling capacity and increasing recovery times from door openings and product loading
• Regularly wiping off frost from sealing surfaces with a soft cloth, will slow down the formation of ice
• Utilize racks and bins to maximize sample storage, reduce air space and manage sample inventory
• Minimize door opening frequency and time of door opening
• Lack of freezer organization can expose samples to unnecessary temperature fluctuations, excessive stress, limit life of operating components, jeopardizing sample integrity
• Use racks and boxes, bar coded tubes, bar code readers, inventory management systems to locate samples. Quick location of samples, less time freezer doors are open, minimizes frost and stress on ULT

ULT’s should be place on a regular defrost maintenance schedule. We recommend once per year. That can vary depending on daily usage and maintenance practices.

Steps for proper defrost…

• Samples will need to be removed from unit to be defrosted
• Shut down the unit
• Open inner and outer doors, allowing freezer to warm up and ice to melt (24 hours recommended). Place absorbent pads around base of unit to prevent slip hazards
• Unit should be thoroughly dried before placing back into service
• Allow unit to pull down to operating temperature prior to reloading samples (12 hours at setpoint before loading)