0304 Fridges and freezers maintenance


This document describe the maintenance of fridges and freezers at KI Biobank


To describe the maintenance of the freezers and fridges at KI Biobank.  


The instruction includes all the freezers and fridges at KI biobank that are not connected to an emergency alarm.


  • The laboratory staff at KI Biobank is responsible for making sure that this instruction is being followed.
  • The biomedical technician who created the instruction is responsible for updating it.

Reference document

Manual fridge ER8710C, ER8710CX, 818 20 83-00/9, Electrolux

Manual freezer EU8112C, EU8213C, 818 21 28-00/2, Electrolux

Manual for TEFCOLD TFF370 freezer, TKK400 fridge, TFK380 fridge/freezer, KEBO Lab

Manual for Ninolux fridge and freezer.

Manual fridge/freezer Cylinda KFZ 1185 A+.

Maintenance different fridges and freezers


All the weekly maintenance should be documented in the log sheet for fridges and freezers (Loggblad för Kyl och frys). Yearly maintenance, other events, and service should be documented in the Event-log (Händelselogg).

Every week

Every week the temperature on all fridges and freezers should be checked and noted in the log sheet for the corresponding fridge/freezer. All fridges and freezers have a termometer inside.

For the fridges and freezers of the Biobank placed on level 3, the maintenance is done when needed, but at least every second week.





+3°C – +7°C

Freezer -20°C

-18°C – -22°C


When the temperature is outside the given interval it shall be adjusted, see the manufacturers manual. Note your action in the Event-log.



Yearly maintenance

Cleaning and defrosting should be logged in the Event-log. Vacuum/clean the condensator on the back of the  fridge/freezer once per year.


At least once per year, or when needed, the fridges should be cleaned with detergent and water.

1.Place the content of the fridge in another functioning fridge with space.

2.Turn the fridge off and pull out the cable from the wall socket.

3.Take out loose parts and wash them.

4.Clean the inside of the fridge by using a soft cloth and a mild detergent diluted in lukewarm water.

5.Close the door of the fridge when it has dried.

6.Put in the plug and start the fridge. When it has reached the right temperature, put the content back.



At least once per year or when the layer of frost is 3-5 mm thick the freezers should get defrosted and cleaned with detergent and water. The defrosting goes quicker if bowls with hot (not boiling) water are placed in the freezer.

1.Place the content of the freezer in another functioning freezer.

2.Loosen the outflow gutter (at the bottom of the freezer) from its resting position by pulling it straight out, turn it, and put it back in again. It shall form a canal for the water to run in.  

3.Put a freezer box or another suitable box under the outflow gutter to collect the water.

4.Carefully scrape off the ice as it starts to melt. Use a scrape of wood or plastic, not any sharp objects that can damage the interior.

5.When all ice has melted, dry clean, and put back the outflow gutter in its resting position.

6.Start the freezer. When the temperature is stabilized at -20°C put back its content.

Moving freezers and fridges

When a freezer/fridge is moved, this should be noted in the Event-log and the temperature should be logged afterwards.


When the alarm on the freezers goes off, a loud signal is heard. Find out what is causing the alarm and fix the error. Look in the manufacturers manual if you need help. If the problem cannot be fixed the content should be moved to another freezer until it is.  


Document all alarms and solutions in the Event-log.



SOP collection, KI Biobank. 0304 Fridges and freezers maintenance. The Molecular Methods Database. 2016/01/20

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