Johnson temp controller - line for probe

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malkore

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Is it ok to just run the temp controller's probe over the edge of a chest freezer, and just let the lid close on the lead to the probe?

its thin enuf it should affect the freezer from sealing well, but can it damage that wire at all?
 
I drilled a hole in mine and caulked the probe in. But you have to be absoltely sure that there aren't any Chilling coils where you drill. There are USUALLY lines only in the sidewalls (you can often tell by the frost lines that form on the inside surface). So, if you can usually drill through the bottom of the box-out for the compressor right above it. It makes for a much neater installation as you can probably mount the control in the compressor recess as well.
 
That should be fine as long as you don't kink the capillary tube in any way, or allow anything to rub on it in such a way that it will eventually abrade through.

The remote bulb and capillary tube are charged with chemicals (mostly refrigerants) that expand and contract in response to temperature changes. The expansion and contraction acts on a diaphragm, which in turn opens and closes a set of contacts.

If the remote bulb and cap tube lose that charge it will render the control useless.
 
I had no idea these were physically operated. I assumed they were electronic and used a thermistor.
 
Just for clarification. Depending on whether it is a digital controller or an analog controller will dictate what type of sensing element it has. An analog controller will have a remote bulb and capillary tube (see photo on left), while a digital controller will have a thermistor and wire.

johnson-controller.jpg
digital-temp-controller.jpg
 
Ah, I see. I have a digital controller, so I've never seen one of the analog ones up close.
 
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