Using An Immersion Heater
Now you have your Love Brewing Immersion Heater it’s important to understand the capabilities of
this. Depending on where you are doing the fermentation its worth trying this in water before you
start using it on the fermentation. This way you can check to see if it will accurately record the
temperature, you are looking for.
Take a bucket of water and record the temperature on your thermometer let’s say its 20C. Set the
Immersion Heater to 25C and place in the water. You can fully submerge this as it’s a sealed unit.
Your room temperature must always be at least below the temperature you set on the Immersion
but for this purpose we suggest room temperature should be between 20-22C. Depending on this
and the volume of water your liquid temperature should rise to the set level on the Immersion. If
this doesn’t happen check firstly your thermometer (digital strips stuck on the outside are not that
accurate) is reading accurately. Then try increasing the reading on the Immersion to say 30C and
again leave the bucket of water for several hours and see what this is doing to the liquid. It might be
the temperature increases (but not to the full amount). This will then give an idea of how accurate it
is. The light is on when the Immersion is supplying power.
Once we are happy that the reading are there or there abouts (we are never going to have it dead
accurate so please allow some tolerance) we can then start to use it.
If our fermenting room is really cold its essential that the liquid temperature is over 20C (especially
fermenting 23 litres or more of product) at the start of fermentation. The Immersion is good at
maintaining temperatures, but it will find it hard raising the temperature quickly. So, with this in
mind if the room is cold it might be necessary (won’t do any harm to do it) to protect the container
but insulating it with say a blanket or a duvet. It’s also important to have something under its base
like foam or the likes if it’s sitting on a hard concrete type of floor.
One thing we know is the yeast will create heat in the container when it starts fermenting and
converting the sugar to alcohol. This will totally distort the readings so it’s important you bear this in
mind and why when you are testing the Immersion you only do this in water as opposed to a
fermented mix. For example, if we were to set the immersion to 25C (room temp of 24C) the liquid
could rise to 27C and unless we were looking at the Immersion every minute (to see when it
switches off) we couldn’t tell if it were accurate. Similarly, if we set it to 20C on the immersion and
the room temp is 23C the immersion would appear to be switched off. Is this because it got to 23C
or is the yeast heat causing this who knows?
So, when we come to use the Immersion always think about your range. If we want a liquid temp of
22C then we should set it so we can achieve this of say 20C (allowing for the increase in
fermentation heat of 2 to 3C we would then be in the range of 22-23C). Room temperature must be
less than say 22C.
If we are looking for 23C and the room temp is 25C then the Immersion won’t be working (should
switch itself off) but the liquid temp could rise to 28C. We just ask you bear all this in mind.
All I can say is that it’s so much easier testing your Immersion in straight water to find out where you
are with it. If you are having doubts, then let the fermentation finish and then try doing this in water.