Should I change temps to maintain flow rate

[Neelin01]

I have a t500 reflux still and I am just starting to be able to drive it properly. The burner is one temp it has no temperature control past on or off. The temp of the condenser is regulated by water flow. Water flows through a condenser in the stack and causes reflux which gives me the good stuff. I find myself raising the temp a few hours in to keep the distillate flowing at the same rate. So I start at 55-56 and then end up adjusting it over about an 8 hour period to up to around 60 celsius
I have had some pretty great batches so far. And a few terrible ones also. I am having a lot of success making a great neutral with the all bran recipe. I am curious if anyone could tell me if Im hurting quality by chasing the flow rate of the good stuff by raising the temp in the stack? If I didnt do that it would take double the time to do a run. Or I would get a lot less product haha.
Im not the best at tasting cuts yet so Ive been keeping the middle 50% as hearts and the first and last 25% go into my next run.

[Pikey]

Ok I don't have a t500 but we know it uses the water discharge temperature to manage the reflux.

Yes letting the temperature rise will increase your flow rate and decrease your ABV. There is a guy on You tube who tries to use one to make brandy by letting the temperature go high, so as to drag some flavour through.

However, if you search the T500 on the internal google search the site uses, you will find in the older posts "Rad" insists that it is unsafe to let the temperature get over (I think) 85 degrees as it damages permanently some of the plastic components within the column. There is now some discussion as to whether these components can be replaced with "safe" materials which would allow us to use it in accordance with the rules of the site !

Anyway, I believe the T500 is supposed to "shut itself down" before Tails get produced and they become marooned in the still, so I'm sure someone who has run one will be along to clarify this point, but if so, there is no need to make a "tails cut".

In answer to your question then - yes it is ok to let the temp rise, your abv will decrease as it does so - but don't let it over 85 C.

[jb-texshine]

If the burner only has an on or off switch how do you control the temp? Never seen one in person.
Jbt

[Pikey]

If the burner only has an on or off switch how do you control the temp? Never seen one in person.
Jbt

With a coolant managed still, you just reduce the cooling water allowing the reflux chamber to increase in temp and the cooling water comes out hotter.

[jb-texshine]

As an,I see.

[Saltbush Bill]

Your better of running you T500 by watching the flow rate rather than the temp.
I know this because I ran one many many times when I first started distilling.
The slower the out put rate, the higher the abv, and the purer and less taste the spirit will have.
The faster the output rate , the lower the abv , the less pure the spirit.
If you want quality you disregard the temps and keep the output real slow.
Do not believe the owners manual or anyone who tries to tell you that you dont need to make cuts when you use this still, nor that it wont produce tails. That is complete nonsense.
The other thing that you can do to dramatically improve your product is to build a pot still head for the boiler and then strip your wash before refluxing it.

[jb-texshine]

Sbb,tell me if I got this right,
A cm still is basically a packed pot still with forced reflux and should be driven like a pot still-control the output speed for best results. But instead of using the gas pedal to control it you use the brakes. If I understood what I read.
Jbt

[Saltbush Bill]

JB your analogy is pretty well spot on in this case. These stills are a small commercially made Still. They have an electric element to heat the boiler which works at a set heat.
In short you have no control of the amount of energy supplied to the boiler, so the only form of "Braking" you have is by adjusting the volume of water flow.
Turn the water up and the reflux condenser becomes cooler, in turn knocking down more vapor, in turn more reflux and less spirit leaves the still.
In short the vapor has to be able to get past the reflux coil to leave the still, you are just limiting how much gets past that coil by adjusting the coils temp.
What cant pass the coil goes back as reflux.

[HDNB]

perhaps you mean...as the run goes to tails output slows? and you want to reduce reflux to restore flow rate?

in that case, i'd suggest running as stable as possible, without change during hearts. even as output slows towards the tails transition.

when you change out collection vessel for a cut of tails, turning down the reflux may help you finish stripping tails out quicker.

[ShooterNZ]

@OP

I have a T500 wth copper column.

I think you meant boiler and NOT burner.

The alcohol flow is entirely controlled by the cooling flow rate via the small needle valve. I believe 55 degrees C approx is optimal. Alcohol will stop flowing below 50ish

Problem is ..the need to control the needle valve in micro moves due to inconstant water pressure and other demands on your water supply that affect water pressure (or is it flow)

I have a water regulator on mine that makes it a lot easier to control. A pump in a reservoir controls the flow to the cooling head.

[Saltbush Bill]

If your hooking one of these up to a kitchen tap or such try turning the tap down real low ..it sort of acts as a pressure regulator and helps the needle valve supplied with the still to do its job a little better ...not perfect , but does help in my opinion