How accurate is a hot water cylinder thermostat?

[Chris123]

Hi, it's a final sealant tank on an anodising line. It's a Nickel Acetate based sealer, if it boils it destroys the anti-smut additive. Although this is really only a problem on black colours, it would be nice to stop it happening!

 

[Chris123]

Currently using a deep fat drier from a takeaway, which isn't accurate at all!

 

[Ermintrude]

If you can jacket tank and have some sort of stirrer or de stratification device. Ransome orbital sander plate under tank? Use a wet pocket probe or two?

Heat the jacket with water from a thermal buffer (20 times the volume of the jacket) ?

 

[happyflyer]

Currently using a deep fat drier from a takeaway, which isn't accurate at all!

The thermostat on a deep fat fryer will have an even more wild hysteresis, +- 20 Deg C no reason for it to be accurate with chip oil....they used a long rod type thermostat

 

[Ermintrude]

No he is using the fryer element and stat in the frying bath. That's what he meant to say. HSAWA and HAZOP really ring a bell!

 

[happyflyer]

Ermi,

" put mi to fish in please"

 

[Ermintrude]

K? You want your fish cooked in Ni solution? Make your fillings go funny?

 

[Bronze_tap]

Ideal temperature is 96c, but could go as low as 90.

It looks an ideal case to be heated by steam at 100C at atmosferic pressure, passing through the coil (you can rip the top of the suitable unvented stainless steel cylinder to be used as a bath.) and connect the coil pipe to another boiling tank/steam boiler, so that the condensate can run back into it. (Provided yours process i OK with stainless steel walls).

 

[Ermintrude]

If you take the lid of an unvented cylinder and boil the water in it it will splay open like a yogurt left on a stove top. The lid acts as a structural part of the cylinder . Plus open top will create a thermal gradient through bath. Why go to the hassle of raising steam when he could just use an element?

Best to keep cylinder closed but vented and have a small closed jacket. Vented essential as no one likes flashing to steam.

 

[Dotty]

Bronze tap.

I'm watching you now.....