[FONT=comic sans ms,sand] Thermostat Modification[/FONT]​
Do not try this yet! I really have no idea what I'm doing? This is Just a Test!
I've never done this befor but not afraid to trying anything once... Well almost anything.
I'm trying to get rid of the inherent 10degree temperature swing of the typical hot water heater thermostat.
This is just an experiment I have never seen the inside of one of these befor.
I'm hoping to find out what makes this thing tick and tweek it to my liking.
Step 1 ... drill out the 2 rivets holding the backing plate on.
In hindsight if you remove or pull back the degree setting sticker from the front it will be easier to drill them out.


The rivets are out. Lift the back cover off. The round matilac disk appears to be the heart or "ticker" in question.
Do not bend or mess with the "ticker" or it may never work properlyagain. Some kind of special looking spring steel IDK?

When the disk is heated it expands this pushes down on the plunger witch turns the circut to the off position
& when the disk is cooled it retracts and releases the plunger turning the circut back on that makes one cycle.


This first pic shows the plunger my first idea was to alter the length of the plunger making it slightly shorter.
I found that an ink pen tube fit in the hole. It's e-z to cut no problem cut one up & give it a go.


I started out on the long side with the new plunger then trimed it off. Now to put it back together & see if it still works.
Just center the "ticker" back in place & slip the back cover on, align it to the 4 small pins around the circle.
If the "ticker" is not centered properly it will not go together. A little tricky but not bad.


I'm using a zip-tie to hold it together for now as I'm sure I'll be back inside it soon.

I tested the switch out in a small box for awhile after the plunger change + or - .5 to .7 degree swing getting much better...
After I test this out under real incubating conditions and I'm 100% sure It works "I'll Let The Cat Out Of The Bag"
Update 8/30/09 This Is The Good Part
"The Cat Is Out Of The Bag"
I put the stock plunger back in and was able to drill three 1/8" holes in the bakelite housing this
modification allows a much faster air transfer rate to the "ticker" Say goodbye to temp swings.


One or two holes may have been enough but I figured the more the better & went with three.
I tested the switch out in the small box again for awhile "O Degree Tempeture Swing"

Yes I Said "O Degree Tempeture Swing"
I now have this setup just laying in the Sink-A-Bator 99.5 Degree Air tempeture & 99.5 Degree wiggler tempeture all day long!!!
Give this a try you'll be glad ya did. This works!