Useful p/stat replacement?

[chrisnotton]

Ciao e tutti,
For those of you with a HX machine who fancy a bit more control but without PIDing this might be an interesting upgrade:

http://www.cse-distributors.co.uk/contr ... switch.htm

It has range & differential controls so you can set the pressure that your element switches off and also the drop before it comes on again. This should allow you much closer temp control than the standard p/stat.

The spec. says 1/4" connection but doesn't say BSP so it COULD be some other 1/4" I suppose. All this for £29. I'm thinking of buying one to play with

Pip pip
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[Ian]

It only goes up to 100C, a HX boiler will be around 120C.

Nice try though.

[chrisnotton]

Hmmm.

Well If it lives at the end of a long tube like most stats, i.e. not directly mounted on the boiler itself it will stay much cooler than the boiler temperature. I can comfortably hold the pipe at the stat end on my machines.
Here is the spec. of the standard p/stst:
http://www.signal-lux.com/frame-products.html (click on pressure switches & then M3)

You will see that it is spec'd at 85c. This might be one of the reasons that manufacturers stick 'em on the end of long tubes. I guess they can then buy industry standard switches with nitrile diaphragms. I could never figure-out why they did this, could be to keep the temp within the switch tolerance and the stat away from the hot boiler.

I have also had a nice manufacturer offer to send me a free sample of a close tolerance (<.1 bar differential) p/stat which I'm going to try.

I have an old paper-roll temp. logging machine so I am going to do some boiler temp experiments, with & without pulling shots, & then do some brew-temp readings to see what difference the switches make.


Pip pip
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