Boiler Temperature Control

[packapoo]

I wonder if any of you who have ability to control boiler temperature, as in using your BM or GF as a still boiler, would care to share your operational views/advantages? (Or otherwise).

I'm thinking of two possibilities for my set up. Either mate my PDA-1 to a T500 lid to mount on my GF, or setup one of the cloned GF STC controllers I have, to run my existing boiler. The boiler does have a thermowell which makes that option simpler. All I have to decide is whether to plug my present boiler control, which is a little hit-and-miss as far as real control goes, into STC or bypass the present control entirely in favour of STC.

Any thoughts you might have would be welcomed.
As an aside would I be right in thinking if initial run temp were set at fores tops, would that automatically ensure all fores were extracted at any one time during a run? Similarly, same could be done for heads and hearts?

[Anavrin]

Hi packapoo

You can't control the temperature the contents of your boiler boils at, that's determined by the composition of the liquids inside it, all you can do is regulate the power with an SSR or something similar.

This will enable you to smoothly turn down the power to a required level during a spirit run.

If you tried to use an STC set at a particular temperature to control the boiler temp, all that would happen is once that temp has been reached the power will be switched off and it will stop boiling until it's cooled down enough for it to start again, we need a continuos boil that constantly produces vapour, so a power regulator is the way to go.

[Easydrinker]

I think Anvarin gave you a fairly complete answer, but will add this.
With my VS Still, once I have set a boiler temp.- with my SSR controller, time is the controlling factor, as my cooling is more or less fixed.
As with many here, after full reflux and then the heads have come off, nudging the boiler input up starts the hearts.
In my case, for some reason, Style and scale of metalwork, ambient air, whatever,... Tails don't start.
I got lucky maybe

Robert.

[packapoo]

Thank you for your response, gentlemen. That's all pretty clear.

As to yours Anavrin, realising the STC will switch off at set temp, my thinking was by eyeballing, at temp drop increase temp to get rolling again to the next phase. Then ditto repeato.

[packapoo]

Further to previous, I'm hesitating to going for a Still Dragon SSR controller kit. While price isn't big there's still (get it?) a question in my mind as to accuracy of dial to power output. Does anyone have any knowledge of these, please?

My present is a burst-fire controller which I have configured as a clock face: off @ 7 o'clock, full tilt @ 5 o'clock. I don't believe the in-betweens fully reflect the true power inputs. I run it thru a plug in power meter showing wattage as a guide but still have doubts.
So, will SSR be an advance?
I've just finished a new brew shed where among other things, electric circuitry should reflect stability in power usage on my meter, but Murphy's being what it is.....

What I'm trying to do is get correlation between boiler temp and output temp to optimise off-take. I have seen claims this is worthwhile but perhaps I've missed something....

[Myles]

Burst fired and SSR do the same thing but by slightly different methods. I use both and they both give variable power outputs over a rangeof values. It is usefull to check what the variation is, even calibrate them.

To do a propper job you need to measure both current output and voltage output as on most controllers these BOTH vary constantly.

This was a PSR 40 connected to a 6 kW element in %age of max power.

[packapoo]

Cheers for that Myles.
Going over things last night came to conclusion that the two must be pretty similar. To that end had another think and sorted out a way to proceed.

[Myles]

This might be usefull.

K613L1r3(using thyristors).pdf

(40.8 KiB) Downloaded 247 times

[packapoo]

Very interesting reading. Thank you Myles.
I'm glad I settled on what I have plus a work-around.

[Easydrinker]

Beyond me boys, I tried to follow and failed.

But this often happens to me late at night after a shandy or two

Robert.

[packapoo]

Happens to me frequently Robert, so you're not alone.....

[RumJohn]

Cook on gas. Much easier to control.

[Easydrinker]

I would question that, but may concede to scale.

Robert

[RumJohn]

No question at all Robert. Only becomes difficult to control when it pukes and the whole thing catches on fire.

[Easydrinker]

That does make me feel that electrically controlled heating is the best choice for me.
I seem to be able to keep that controlled. Safely.
As I said,
scale, and maybe experience, are the things in play here.

Robert.