Chinese Incubator Temperature

[Skewbald]

I have a Chibese 48 egg incubator suddenly on day 11 temp has dropped to 30.5 and won't go up.

 

[ChickenCanoe]

As you are aware, that is much too low. Have you verified the temperature with a proven accurate thermometer or relying on the incubator reading?
At what stage are the eggs and how long has this been going on?

 

[Skewbald]

As you are aware, that is much too low. Have you verified the temperature with a proven accurate thermometer or relying on the incubator reading?
At what stage are the eggs and how long has this been going on?

The probe says even lower - 28C
We're on day 11 and it just happened today.

I've got the thing wrapped up in blankets since it's struggled to keep 37.5 but it's not been far off. Today it suddenly dropped.

 

[ChickenCanoe]

With the blankets, are the air holes still uncovered?
If it is struggling, it may help to build a wall around it with cardboard to hold warmth in yet still allow airflow.
But what kind of thermometer are you verifying the incubator with?
37.5 is good. Incubators with low power heat elements like 40 watts often struggle.