Thermocouple advice needed.

[hughjamton]

I see some people having problems with the sensitivity of their PID sensors when using a thermowell.
So the do away with the thermowell and install the thermocouple directly into the mash tun/boiler.
Are the thermocouples waterproof?
I have some that I would think not, but the photo shows one that looks like it is, and also looks like I could install it without a thermowell.
Has anyone done this?
Can anyone see a problem with it?

 

[OldPeculiar]

I would make sure it's Stainless, also you'll need to make sure there is a good seal between MT and outer wall, maybe with the use of larger washers?
OP.

 

[hughjamton]

I would make sure it's Stainless, also you'll need to make sure there is a good seal between MT and outer wall, maybe with the use of larger washers?
OP.

Definitely stainless, and I'm confident I could waterproof fitting it, it's really the thermocouple itself.
It's not so important inside a thermowell, plus it will have added protection.
However, as I mentioned previously, I seen reports of loss of sensitivity and the thermocouple installed directly.
I just don't know if this one is suitable, it looks it to me, but that don't mean much.

 

[OldPeculiar]

Not sure about the loss of sensitivity, but T/C's are accurate to 1deg F, where as your PT 100- (PRT) are a lot higher 0.1% accuracy.
The T/C looks suitable and looks to have enough immersion into MT, but If you can (and if your PID allows) i would go with PT100 but that's just a personal thing.

 

[JockyBrewer]

Not sure about the loss of sensitivity, but T/C's are accurate to 1deg F, where as your PT 100- (PRT) are a lot higher 0.1% accuracy.
The T/C looks suitable and looks to have enough immersion into MT, but If you can (and if your PID allows) i would go with PT100 but that's just a personal thing.

As the owner of some slightly wonky PT100s that seem to 'wander' occasionally (not figured out why...), I'd be satisfied with a lower resolution T/C if it's accurate.

 

[BeerCat]

I installed one directly into my mash tun but never use it. I found the temperature was to variable so I have mine on the output. Mine has not rusted but I have one like in your photo that has. Quality is very dubious. I use the NPT ones.