Brew System – Hot Liquor Tank By: Tom Ayers
Brew System – Hot Liquor Tank
This week I’m going to continue my series of articles on my brew setup. In this article I’m going to discuss my Hot Liquor Tank (HLT). As with any three vessel system my Hot Liquor Tank is used to store and heat water for use in the mash and sparge, but it also doubles as a HERMS system. HERMS stands for Heat Exchanged Re-circulating Mash System. My system is modeled after the Theelectricbrewery.com. I’m writing about my version of it in particular to show that a complex system like this can be built by someone with no electrical knowledge. For additional support, please check out the website as it is a great resource and is extremely detailed.
Note: Electricity and water do not mix (well they do, but trust me it’s not fun and can kill you if not properly put together). Proper safety methods need to be applied including GFCI protection. Because I am neither an electrician nor an expert of any kind I will not be showing the electrical connections. Please refer to theelectricbrewery.com for further instructions.
Let’s start with some visuals. The first picture is an external shot of my Hot Liquor Tank. This is the first vessel I ever bought that was big enough to full 5 gallon boils. It is a Bayou Classic 15 gallon stainless steel kettle. It is an acceptable vessel, but there are better options here on love2brew. There are four ball valves attached to the tank along with a 5500W hot water heating element. The two valves aligned vertically on the left side of the kettle are the entry and exit valves for the HERMS coil. The valve in the middle of the picture near the bottom is the exit valve for the water contained in the tank, while the top right valve is the return valve for water going into the tank. On the bottom right of the vessel there is a box that contains the electric heating element connections. This is water tight for safety reasons.
In the next picture you can see the HERMS coil connected to the two valves on the left side of the first picture. In the bottom you can see the drain valve and on the right of the picture is the return. Lastly, it is difficult to see but the heating element is in the bottom of the vessel.
Basically the way my HLT is used in my brew day, is the entire volume of water I need for brewing the batch of beer is placed in the HLT. It is then heated to my strike temperature for the mash. While heating, the water is re-circulated out of the bottom drain and back into the top return valve. This serves two purposes. First, it mixes the water to ensure and even temperature through out, otherwise the temperature would vary the further away from the heating element you got. Secondly, the temperature probe that measures the temperature of the water is connected to the drain ball valve. You could put the probe in the HLT directly and it could serve the same purpose, but you would still need to re-circulate to achieve the desired temperature across the entire volume of water.
Once I hit my strike temperature I pump out the necessary volume to the mash tun and maintain the remaining water at my desired mash temperature for use during the mash as part of the HERMS setup. I’m going to go into greater detail on the HERMS coil in my next article on the mash tun, as it is an integral part of that vessels function. Once the mash is over I use the rest of the water as needed to sparge the grain and hit my pre-boil volume/gravity. If any water is left over it is used for cleaning.
To make the HLT function it plugs into the control panel for power and temperature monitoring. The valves connect to hoses that run the liquid through pumps to re-circulate and transfer. I’ll cover the control panel, pumps and hoses in future articles. The vessel is able to maintain temperatures with in 1-2 degrees with no additional insulation required. I’ve even brewed outside in 32 degrees Fahrenheit and it was able to dial in my mash temp and maintain it. Having the lid is useful for several reasons. It cuts down on noise from the re-circulation of the water, eliminates any splashing that may occur if you are filled to the rim, and lastly but most importantly it helps retain heat making raising the temperature faster and holding temperature easier.
One additional note about the HLT is that with the exception of the inside of the HERMS coil it never sees wort. For cleaning I simply drain the water and dry. To clean the coil I re-circulate warm oxi-clean through the coil and flush with water. It is a clean is place (CIP) vessel.
Next time I’ll start up the discussion about my mash tun. Until then drink up and brew on.
As always, if you’d like more homebrew information, follow me on twitter @Tom_Ayers. If you have any questions, comments, or topic requests send me an email at AyersBrewing@gmail.com and I’ll be sure to respond. Until next week, cheers and happy brewing!