Thumper size revisited

[Haus]

Is the thumper size based on actual boiler size or maximum liquid volume with sufficient overhead?

[Da Yooper]

Your thumper should be atleast half the size of the boiler, no less. Parent Site has some readings on thumpers , check it out.

[SassyFrass]

I am currently in the process of building a new pot with 2 thumpers in line. the pot and both thumpers are 15.5 gal kegs. I won't be able to say anything good or bad about it, until I run it a few times.
having said that:
I ran a 15.5 gal boiler with a 5 gal thumper for years. Now those are capacity, not charge levels. I seldom charged the boiler with more than 12 gal, and the thumper was usually charged with 1/2 gal'ish. I usually just eyeballed it and made sure the input spout was covered by about an inch or so. Then, if I shot the thumper midrun, I'd still have sufficient room in the thumper.
There are folks that run smaller than recommended thumpers but I never have.
I've always heard that 1/3 to 1/2 was best size for thumper.
Just my $.02

SF

[Haus]

Don't get me wrong, I have upgraded to 1/2 the size of the boiler. In doing so I began to wonder what it was based on. Example: If you had a 10 gal boiler and a 5 gal thumper but only did runs of 5 gal then the thumper would be over-sized for what is going thru it. Which kind of makes me think it's the maximum possible liquid volume of the boiler. It may be one of those apples and oranges things and easier to just say 1/2 is good. I'm just more curious about the science behind it, that's all.

[Usge]

It's based on the output capacity of your still. Having one too large is not going to hurt anything up to a point. Having one too small will (it will overfill and puke). Because you will be running "different" still charges...both in terms of volume and abv, your sizing choice needs to be based on your "max" volume......not your minimum. Look at the max output volume ....for running max capacity (12 gals for a 15.5 gal keg) of 40% (which is as high as you should safely go). That's what the still is going to 'produce' into the thumper when you go through the run. Then add to that...room for whatever you might plan on adding to the thumper to start with. Then add to that...some headroom. If you are like most people...you should come out somewhere around 1/2 the size of your boiler. And as I said..going a little bigger isn't going to hurt anything.

It's a rule of thumb...based on a lot of variables (you could be running wash, less than full still charge, etc). So, having "extra" headroom...is not going to hurt anything.

[skow69]

I run a 5 gal pot with a 1 gal thumper. If I charge the thumper with 1/2 gal or less it never pukes. If I charge it with 3/4 gal it pukes.

[Haus]

It's based on the output capacity of your still. Having one too large is not going to hurt anything up to a point. Having one too small will (it will overfill and puke). Because you will be running "different" still charges...both in terms of volume and abv, your sizing choice needs to be based on your "max" volume......not your minimum. Look at the max output volume ....for running max capacity (12 gals for a 15.5 gal keg) of 40% (which is as high as you should safely go). That's what the still is going to 'produce' into the thumper when you go through the run. Then add to that...room for whatever you might plan on adding to the thumper to start with. Then add to that...some headroom. If you are like most people...you should come out somewhere around 1/2 the size of your boiler. And as I said..going a little bigger isn't going to hurt anything.

It's a rule of thumb...based on a lot of variables (you could be running wash, less than full still charge, etc). So, having "extra" headroom...is not going to hurt anything.

Very Good! Thank You

[Truckinbutch]

Same size boiler and thumper are working well for me . Gives me the flexibility to run however I wish to run .

[LWTCS]

There are some variables. Ambient temps being the first that come to mind.

As I recall Dunderhead used to say that a" rule of thumb " for rendered low wines for a strip run would be about a 3rd of the total primary boiler charge.
So for me 1/3 is the rule of thumb.