How does a wafer work and when do I need a new one?

[johnnalei]

I just bought a new Hova-bator and I'm very confused with the whole thermostat thing. It took me a couple of days of tinkering with it just to get the temperature up. I think it's been an error on my part, but how does the wafer work? How will I know if I need a new one? Thanks!

 

[Nemo]

When the wafer heats up, it expands, and gets thicker. You turn the screw it is attached to to move the wafer closer to or farther from the switch. When the wafer is closer to the switch, it doesn't need to heat up / expand as much to click the switch and turn the heat off. When the wafer is farther from the switch, it needs to heat up / expand more before clicking the switch, so the incubator gets hotter.

If the temperature in the incubator ranges widely, like mine did, then you should get a new wafer. It has ether in it, which can escape after years, so it doesn't respond as quickly as it should.

 

[johnnalei]

Oohh, I understand now!! This also would probably explain the difficulties I was having setting it up. Thanks!

 

[adrian]

I really don't want to risk putting eggs in and having my wafer thermostat fail, so after how many years should a thermostat such as this be replaced? My current incubator, which will be used as a hatcher when I receive my Genesis, is a Hovabator turbofan model. I've had it for two years.

 

[Nemo]

I have no idea how long they [should,do] last. Mine was in a 'bator that's prob'ly older than me. It was up in a co-worker's garage for a number of years. I have no idea what happened to it before that.

The wafer does flex as it expands/contracts, so it will wear out eventually. I guess the best advice would be to have a spare on hand. When your temps start to vary too widely, then it's time to replace it.

 

[DANNY]

The wafer system consists of a wafer and a micro-switch. When the wafer expands from being heated it pushes the little point sticking out of the micro-switch in breaking the connection and turning off the heating element and when it cools it retracts turning the heat back on. I change my wafer and micro-switch every year to avoid problems though they will sometimes last for years. I use the ones i take out of the bators in my brooders because the temperature don't have to be as precise.