The +2ºC to +8ºC safe margin may be difficult to maintain, especially for a kerosene refrigerator, so you should frequently check the condition of the vaccines. Here we give some guidelines on what to do if the temperature of your refrigerator becomes too low or too high.

Kerosene and gas refrigerators

The temperature of a kerosene or gas refrigerator is adjusted by increasing or decreasing the size of the flame. If the temperature inside the main refrigerator compartment is too low, you can increase the temperature by decreasing the flame size. A smaller flame means less cooling, so the temperature in the refrigerature will rise. If the refrigerator temperature is too high, you can reduce it by increasing the flame size. A bigger flame means more cooling, so the temperature in the refrigerature will fall. Monitor the change in temperature frequently – about every 15 minutes – after adjusting the flame, until the temperature remains steadily between +2^oC to +8^oC, to ensure that it does not rise too high or fall too low.

Electric refrigerators: if the temperature is too low

If the refrigerator temperature falls too low (below +2°C), you should take the following actions:

Thermostat dials in most refrigerators are labelled from 1 to 6, where 1 is the warmest and 6 is the coldest setting.

• Adjust the thermostat so that the arrow points to a lower number, e.g. if the thermostat dial was set at 5, adjust it to 4. This will make the refrigerator get warmer.
• Check freeze-sensitive vaccines to see whether they have been damaged by freezing. You can do this by using the shake test, which you learned about earlier (Section 6.3.3).

Electric refrigerators: if the temperature is too high

If the refrigerator temperature becomes too high (above +8°C), you should take the following actions:

• Make sure that the refrigerator is working. If not, check if the power supply is present.

• Check whether the door of the refrigerator or the freezing compartment closes properly. The seal may be broken, allowing warm air to leak into the refrigerator. If the seal is broken, it will need to be replaced.
• Adjust the thermostat so that the dial points to a higher number, e.g. if the dial was set at 3, adjust it to 4. This will make the refrigerator get colder.
• Check whether ice is preventing cold air in the freezing compartment from entering the refrigerator compartment. If the refrigerator is blocked with too much ice, it may be necessary to defrost it (remove the ice).

If the temperature cannot be maintained between +2ºC and +8ºC, store vaccines in another place, such as a vaccine carrier, and try to get the refrigerator repaired as soon as possible.