Australia & New Zealand Homebrewing Forum

Help Support Australia & New Zealand Homebrewing Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
1 hour later and the G40 is back at 22⁰ and it has brought the unitank back down to 22.8⁰ after raising 4⁰ overnight (peak yeast activity)
Luckily it's fermenting under pressure so I should prevent the horrible esters from fermenting too high.


It's important to remember the set temp on the G40 is not the set temp of the desired temperature of your fermenter. Your set temp needs to be significantly colder. For instance if you want to get down to 0C in the fermenter you need to make sure the liquid in the glycol tank is -10 for instance.

Then what you would normally do is have a separate temp controller that cycles the pump on and off so when the 0C is reached in the fermenter the pump is cycled off. Is this how you have it setup. It would be handy if you can send me some photos of the whole setup and also let me know what the temperatures set point is on each controller.

It sounds like your G40 has good ventilation but I have a funny feeling that something in the setup is not quite optimised.

Also if you can tell me:

1. The l/min the liquid is flowing through your chiller coil? So in other words if you get the return hose that goes back to the G40 stick this in a bucket for 10 sec and then measure how many ml of liquid is collected.
2. If you have a temp controller then if you measure the difference in the glycol going out of the G40 and back into the G40 can you please tell me the difference in these two numbers and I can use this to work out how much heat is being absorbed by your coil.
 
It's important to remember the set temp on the G40 is not the set temp of the desired temperature of your fermenter. Your set temp needs to be significantly colder. For instance if you want to get down to 0C in the fermenter you need to make sure the liquid in the glycol tank is -10 for instance.

Then what you would normally do is have a separate temp controller that cycles the pump on and off so when the 0C is reached in the fermenter the pump is cycled off. Is this how you have it setup. It would be handy if you can send me some photos of the whole setup and also let me know what the temperatures set point is on each controller.

It sounds like your G40 has good ventilation but I have a funny feeling that something in the setup is not quite optimised.

Also if you can tell me:

1. The l/min the liquid is flowing through your chiller coil? So in other words if you get the return hose that goes back to the G40 stick this in a bucket for 10 sec and then measure how many ml of liquid is collected.
2. If you have a temp controller then if you measure the difference in the glycol going out of the G40 and back into the G40 can you please tell me the difference in these two numbers and I can use this to work out how much heat is being absorbed by your coil.
I have done all these things! I ran through an external coil and the temp is 1⁰ higher than the tank. Whilst on the phone to Henry at your shop.
It takes 4 days to get to minus 10 without a load.

THE UNIT IS SET TO MINUS 25⁰.
 
I have done all these things! I ran through an external coil and the temp is 1⁰ higher than the tank. Whilst on the phone to Henry at your shop.
It takes 4 days to get to minus 10 without a load.

THE UNIT IS SET TO MINUS 25⁰.

So if the glycol comes out of the G40 and then returns back to the G40 only 1⁰ higher then it sounds like the G40 is not really absorbing much heat from your fermenter. Do you know the flow rate of glycol through the coil? If you only see a change of 1C we probably need to make the surface area of the cooling coil a bit greater in the fermenter. Do you know how many CM^2 surface area you have on the cooling coil immersed into the liquid in the fermenter? Can you please send us this information.

The more information we have the better we can help you. I know it's a bit of a pain to measure these things but the quality of our advice is limited by the quality of the information we can collect from you.
 
So if the glycol comes out of the G40 and then returns back to the G40 only 1⁰ higher then it sounds like the G40 is not really absorbing much heat from your fermenter. Do you know the flow rate of glycol through the coil? If you only see a change of 1C we probably need to make the surface area of the cooling coil a bit greater in the fermenter. Do you know how many CM^2 surface area you have on the cooling coil immersed into the liquid in the fermenter? Can you please send us this information.

The more information we have the better we can help you. I know it's a bit of a pain to measure these things but the quality of our advice is limited by the quality of the information we can collect from you.
Please read, I disconnected the fermenter and ran through a hermit coil.
The way I had it set up worked fine and could crash the unitank to 0⁰ easily. Now it doesn't.

******* hoop after hoop, your unit is ****** and you won't replace it, get ****** I'll suck up the $700 and buy a SS Brewtech when they are back in stock.
 
@Snake Eyed, with the unit set at -25.3, what percentage/ratio is your glycol solution?
When it did work before Christmas, was the temperature at the preset temp (-25.3)?
Also, have you measured what your solution is now?

Daz
 
According to my calculations you would need to have basically a 50/50 solution.
Allowing for the roughly 8 degree difference between set temp and the systems allowance/operating temperature
 
Last edited:
@Snake Eyed, with the unit set at -25.3, what percentage/ratio is your glycol solution?
When it did work before Christmas, was the temperature at the preset temp (-25.3)?
Also, have you measured what your solution is now?

Daz
When it worked, I had it set to minus 8 and it kept the tank at 3 degree. Once the unitank level dropped and I had dumped all the yeast, I let the unitank raise to ambient and ran the beer through the beerlines, I ran through 2 of the tap coils and the beer froze so I raised the temp and the beers poured well, even filled a couple of kegs.

Now it doesn't chill.
 
Have you a means of testing what ratio of water to glycol you have in the reservoir?
This is important as too much of either can lead to problems. You need the water content to freeze, too little water and your solution will warm up too quick, and likewise, too much water and your solution will ice up.
 
If the unit isn't getting the solution that's in there cold how is adding more glycol going to make it cold?

Read all the posts and watch the video.
 
Here is a good chart for working out your glycol ratio. The 20-25'f at the bottom works out to be 11-14'c.
Screenshot_20200120-165527.jpeg
 
Have you a means of testing what ratio of water to glycol you have in the reservoir?
This is important as too much of either can lead to problems. You need the water content to freeze, too little water and your solution will warm up too quick, and likewise, too much water and your solution will ice up.
I drained all the glycol yesterday because it went yellow and stank.
When it was working it was like a hard slushy.
It only has water now but it still won't chill water
 
If the unit isn't getting the solution that's in there cold how is adding more glycol going to make it cold?

Read all the posts and watch the video.
It wouldn't, too much glycol and not enough water to freeze would result in not getting anywhere near the cold temperatures you need.
 
I drained all the glycol yesterday because it went yellow and stank.
When it was working it was like a hard slushy.
It only has water now but it still won't chill water
I personally would do a 30-33% glycol to water ratio.
The g40 has a 30Ltr capacity. So 10ltrs of glycol and 20ltrs of water. This would mean that the solution would freeze at -15'c, and allowing for the 8'c differential you can bring the solution down to -7'c to put through the fermenter.
My experience is that you need around a 5'c differential to cool, so a -7'c solution should/could be able to get your fermenter down to -2'c.
But obviously all this is moot if your chiller is not cooling the solution down to start with, which is the problem you are having
 
Please read, I disconnected the fermenter and ran through a hermit coil.
The way I had it set up worked fine and could crash the unitank to 0⁰ easily. Now it doesn't.

******* hoop after hoop, your unit is ****** and you won't replace it, get ****** I'll suck up the $700 and buy a SS Brewtech when they are back in stock.

I am sorry that you feel this way and we certainly have not given up on you. With any issue that a customer has with anything we have this approach which is documented in our staff procedures:
1. Assure customer that we will find a solution
2. Diagnose the problem
3. Offer solutions:
3.1 - Return for closer diagnosis/repair if over the phone/email support cannot determine the issue
3.2 - Offer replacement or product alternative.
3.3 - Partial refund if the product has been damaged but the customer still wants to keep the product
3.4 - Full refund

So at the moment we really need to get to the bottom of stage 2 as we cannot proceed to stage 3 without proper diagnosis of the problem.

I will also add that from what I have just been told is that you did not purchase the unit from us either. Normally the first point of call would be to go to the retailer that you purchased the unit from as we also do not have any of the purchase details for the original purchase and we can't refund you if you did not purchase from us.

With that said if you have purchased a unit elsewhere we are still happy to give you whatever after sales support we can. We don't want to make you jump through hoops more than we need you to but we do need to gather information from you so we can complete stage 2 of the process above.
 
It wouldn't, too much glycol and not enough water to freeze would result in not getting anywhere near the cold temperatures you need.

Again read the post. It doesn't have to get to -25. The unit won't even chill water do there's no chance of it getting near freezing.
 


Write your reply...

Latest posts

Back
Top