HERMS on a 10 gallon batch

[Normans54]

Hey everybody,

I have a HERMS system which uses a 1500w heating element hooked up to a Ranco temperature controller and 50 feet of 1/2" copper tubing mounted in an 8 gallon stainless steel pot insulated with reflectix.This system has worked fine in terms of keeping my mash temperatures constant in my igloo cooler mash tun when I am doing a 5 gallon batch. However, I am thinking about turning a large picnic cooler into a mash tun so that I can do 10 gallon batches in the future. My question is do you think that this setup will be enough to keep the temperature constant in a larger batch or will I need more power? I have a 1000w bucket heater and an extra controller that I can use to supplement my current setup (provided that I run it from a different outlet than the 1500w heater), but I am unfortunately limited to using 110v outlets. will this be enough power, or would I have to come up with another solution? Thanks a bunch!

 

[Bellybuster]

I'd say your current setup will work just fine keeping mash temps. Consider the fact that the igloo cooler alone can keep temps to a couple degrees...

 

[ThreeDogsNE]

I use 100 quart coolers as mash tuns for 15 gallon batches in my garage. They might lose a degree, or at most 2, in an hour. I do throw an ancient cheap coat or a jacket over them for overkill during the mash. At times, when I have undershot my strike temperature, 2 1500 watt heat sticks will bring it up to temperature in a few minutes. Sometimes if I'm in no hurry I will just use one to bring it up from room temperature. I'm usually not that patient.

 

[jrcrilly]

Before I started recirculating the mash, I never had sufficient heat loss in my cooler MLT on 5 or ten gallon batches to be concerned about. It was only when I began recirculating that I found that something would be necessary to make up the heat lost in the pump and hoses. That's when I added the HEX. The size of the batch really doesn't matter; if the HEX can keep up with its own heat losses during recirculation all will be well. I use about the same surface area as your setup but with a stainless steel coil; your copper coil will be a little more efficient. It is overkill, I used that size coil because I want to be able to change the mash temperature (step mash, mashout) as well as maintain it during the rest. No problems with ten gallons.