Many of the yogurt makers overheat after running for 8 hours and end up going above the 110 degrees recommended. You can check by testing the yogurt in the second half of the incubation period. Or do a test run with just water. To prevent the overheating you add a light dimmer switch. You can buy a light dimmer in hardware stores or you may order it online.

Click here to view it on Amazon
You will have to experiment with the machine before making a new batch. It does not take long to figure out where the "sweet spot" is on the dimmer to keep it between 100 and 110F.

You may have to play around a little to find the right spot for your machine but when you do, mark it on the dimmer to make it easy to know where to set it.

The easiest yogurt maker is a dehydrator because it has a built in temperature control.
Click here to view a dehydrator.
Click here for directions for making yogurt in a dehydrator.

Comment by Marilyn Alm, author of the forthcoming cookbook, "Louisiana SCD Lagniappe".

"I really, really, really do not like opening my yogurt every couple of hours to check the temperature -- there's too much danger of introducing stray bacteria whenever you do."

"I asked my design engineer husband (his specialty is piping design and fluids) about this, and he said that if the water bath is between the correct temperatures, the yogurt can't go over."

It is better to check the temperature of the water surrounding the yogurt rather than the yogurt itself.