Ask The Brewmasters

hello,

I have a tank in my brewery that appears to be showing signs of having a glycol leak. In the past 2 weeks I had began to notice puddles under a specific BBT. I went and tightened the glycol connections at the top to make sure there weren't any leaks there. After that I topped up our chiller.

This morning there was another puddle under the BBT. I can confirm it is glycol, and from what I can tell it appears to be leaking out of the legs. Each tank leg is on a stainless steel pad, and somehow there is a puddle on each of the four pads despite the water on the floor not being high enough to get over the lip.

The beer inside the tank doesn't show any signs of being contaminated with glycol. Gravity readings have been consistent since fermentation ended.

How would I go about confirming where the leak is on my tank?

Thanks for any help.

Cheers

hello,

I have a tank in my brewery that appears to be showing signs of having a glycol leak. In the past 2 weeks I had began to notice puddles under a specific BBT. I went and tightened the glycol connections at the top to make sure there weren't any leaks there. After that I topped up our chiller.

This morning there was another puddle under the BBT. I can confirm it is glycol, and from what I can tell it appears to be leaking out of the legs. Each tank leg is on a stainless steel pad, and somehow there is a puddle on each of the four pads despite the water on the floor not being high enough to get over the lip.

The beer inside the tank doesn't show any signs of being contaminated with glycol. Gravity readings have been consistent since fermentation ended.

How would I go about confirming where the leak is on my tank?

Thanks for any help.

Cheers

hello,

I have a tank in my brewery that appears to be showing signs of having a glycol leak. In the past 2 weeks I had began to notice puddles under a specific BBT. I went and tightened the glycol connections at the top to make sure there weren't any leaks there. After that I topped up our chiller.

This morning there was another puddle under the BBT. I can confirm it is glycol, and from what I can tell it appears to be leaking out of the legs. Each tank leg is on a stainless steel pad, and somehow there is a puddle on each of the four pads despite the water on the floor not being high enough to get over the lip.

The beer inside the tank doesn't show any signs of being contaminated with glycol. Gravity readings have been consistent since fermentation ended.

How would I go about confirming where the leak is on my tank?

Thanks for any help.

Cheers

hello,

I have a tank in my brewery that appears to be showing signs of having a glycol leak. In the past 2 weeks I had began to notice puddles under a specific BBT. I went and tightened the glycol connections at the top to make sure there weren't any leaks there. After that I topped up our chiller.

This morning there was another puddle under the BBT. I can confirm it is glycol, and from what I can tell it appears to be leaking out of the legs. Each tank leg is on a stainless steel pad, and somehow there is a puddle on each of the four pads despite the water on the floor not being high enough to get over the lip.

The beer inside the tank doesn't show any signs of being contaminated with glycol. Gravity readings have been consistent since fermentation ended.

How would I go about confirming where the leak is on my tank?

Thanks for any help.

Cheers

hello,

I have a tank in my brewery that appears to be showing signs of having a glycol leak. In the past 2 weeks I had began to notice puddles under a specific BBT. I went and tightened the glycol connections at the top to make sure there weren't any leaks there. After that I topped up our chiller.

This morning there was another puddle under the BBT. I can confirm it is glycol, and from what I can tell it appears to be leaking out of the legs. Each tank leg is on a stainless steel pad, and somehow there is a puddle on each of the four pads despite the water on the floor not being high enough to get over the lip.

The beer inside the tank doesn't show any signs of being contaminated with glycol. Gravity readings have been consistent since fermentation ended.

How would I go about confirming where the leak is on my tank?

Thanks for any help.

Cheers

Hi Matt,

One of the most common locations where this type of leak occurs is where a glycol inlet or outlet nozzles welds to the heat transfer surface (see sketchy sketch below).  Thermal expansion (for nozzles welded to the out jacket), vertical loads from piping, and applied torque from a pipe wrench without proper backing are three common causes.  Depending on the size of the leak, you can drain glycol from the tank in question, apply air pressure to the jacket (don't exceed the design pressure), and use a stethoscope to locate the location of the leak.  Temperature guns do work if the leak is big enough, but small leaks are often hard to locate based on temperature.  The good thing about air leaks is that they are noisy and the stethoscope method usually works for even small leaks.

Once the leak is located, your outer jacket will likely need to be cut to allow access to the problem area.  A good repair person will be able to patch the incision with an escutcheon that should not look terrible.

Determining the root cause is important because this sort of failure can occur on multiple tanks if the cause is related to how pipes are installed or thermal expansion.  The latter problem is especially problematic on larger tanks (greater than about 200 BBLs) that have welds connecting the glycol nozzle to the outer jacket where hot CIP is used.  When the inner tank is heated, it elongates.  Because the outer jacket is at room temperature, the weld connecting the glycol nozzle to the heat transfer surface/box header is stressed and fails given enough of these cycles.

If I were to wager a bet, this is where I would place my marker!

Cheers,
Ashton

hello,

I have a tank in my brewery that appears to be showing signs of having a glycol leak. In the past 2 weeks I had began to notice puddles under a specific BBT. I went and tightened the glycol connections at the top to make sure there weren't any leaks there. After that I topped up our chiller.

This morning there was another puddle under the BBT. I can confirm it is glycol, and from what I can tell it appears to be leaking out of the legs. Each tank leg is on a stainless steel pad, and somehow there is a puddle on each of the four pads despite the water on the floor not being high enough to get over the lip.

The beer inside the tank doesn't show any signs of being contaminated with glycol. Gravity readings have been consistent since fermentation ended.

How would I go about confirming where the leak is on my tank?

Thanks for any help.

Cheers

Thank you for all of the replies. 

Shortly after I started this thread I contacted a local to our pub who is an engineer and works in the dairy industry. He gave me this reply exactly as to where the issue most likely occurred. We have 2 inlets to our tank, so we also did the following to help figure out where the leak is.

1. Mix food safe red and green die with water
2. We filled the top jacket with a red die and bottom with green.
3. Then we pressurized the jackets to 5 psi and left them over night
4. in the morning we came in to see which dye was on the ground

We are currently waiting for a welder to come in next week and cut open the outside wall of the tank. Just went over our old drawings and hopefully they are correct, so it will be a little easier to find the appropriate inlets without too much work.  In the meantime I have also started working on getting a new BBT just in case this doesn't workout.

Cheers

Hi Matt,

One of the most common locations where this type of leak occurs is where a glycol inlet or outlet nozzles welds to the heat transfer surface (see sketchy sketch below).  Thermal expansion (for nozzles welded to the out jacket), vertical loads from piping, and applied torque from a pipe wrench without proper backing are three common causes.  Depending on the size of the leak, you can drain glycol from the tank in question, apply air pressure to the jacket (don't exceed the design pressure), and use a stethoscope to locate the location of the leak.  Temperature guns do work if the leak is big enough, but small leaks are often hard to locate based on temperature.  The good thing about air leaks is that they are noisy and the stethoscope method usually works for even small leaks.

Once the leak is located, your outer jacket will likely need to be cut to allow access to the problem area.  A good repair person will be able to patch the incision with an escutcheon that should not look terrible.

Determining the root cause is important because this sort of failure can occur on multiple tanks if the cause is related to how pipes are installed or thermal expansion.  The latter problem is especially problematic on larger tanks (greater than about 200 BBLs) that have welds connecting the glycol nozzle to the outer jacket where hot CIP is used.  When the inner tank is heated, it elongates.  Because the outer jacket is at room temperature, the weld connecting the glycol nozzle to the heat transfer surface/box header is stressed and fails given enough of these cycles.

If I were to wager a bet, this is where I would place my marker!

Cheers,
Ashton

hello,

I have a tank in my brewery that appears to be showing signs of having a glycol leak. In the past 2 weeks I had began to notice puddles under a specific BBT. I went and tightened the glycol connections at the top to make sure there weren't any leaks there. After that I topped up our chiller.

This morning there was another puddle under the BBT. I can confirm it is glycol, and from what I can tell it appears to be leaking out of the legs. Each tank leg is on a stainless steel pad, and somehow there is a puddle on each of the four pads despite the water on the floor not being high enough to get over the lip.

The beer inside the tank doesn't show any signs of being contaminated with glycol. Gravity readings have been consistent since fermentation ended.

How would I go about confirming where the leak is on my tank?

Thanks for any help.

Cheers