Wiring up a TempMate


According to experienced homebrewers, temperature control during the fermentation is second only to sanitation (and perhaps healthy yeast). It’s been hot here over the last few months and I’ve been struggling to keep my fermentation temperatures down to a reasonable level by way of a laundry sink full of water with regular additions of slicker pads from the freezer. So, I went ahead and scored myself a full-sized fridge for just $30 on TradeMe (broken thermostat which I removed and hard-wired to permanently on) as well as a $100 TempMate from CraftBrewer in Australia.

The TempMate allows me to keep a constant 18 degrees (you can set the temperature to anything you like) for my ales by turning the fridge on when it gets too warm and by turning on a heading pad (not needed yet as it’s still too warm) when the temperature drops below that. The TempMate ships with very few instructions as to how to wire it up, and, given that the penalty for getting it wrong is possibly death by electrocution and also keeping in mind that if you are a home brewer you are likely going to wire it up yourself instead of consulting an electrician (undoubtedly with a belly full of beer like I did), I’ve decided to share my setup.

A caution: this is 240V mains stuff and cocking it up really can result in an untimely death so if you are going to do it yourself be very careful.

The best guide I could find was on the Melbourne Homebrewers website and I basically copied their setup so check them out.

tempmate wiring

From Ideal Electrical I shelled out a whopping $50 (I could buy almost two fridges for that!) for a fully sealed enclosure along with two unswitched sockets ($20) — one for the fridge and one for the heat pad — and cable glands ($7) to hold my power and temperature probe cables firmly in place at the back. All of the cabling came from an old computer monitor power cable which I shortened and divided up to make all of the cross connections as well as the main power-in lead. I used a drill, a hacksaw blade and a craft knife to create all the cut-outs and holes. It’s a thing of beauty and it works a treat. Now, to brew a batch of Ordinary Bitter on Saturday morning and keep the bugger at 18 degrees throughout fermentation!

(Here is an unobstructed close-up of the wiring)

Tags: , , , , ,

9 Responses to “Wiring up a TempMate”

  1. Ah, I’m jealous. The only option I had available when I was brewing was a temperature control unit that was designed to work with a window air-conditioner unit – I think it was made by Hunter. It was designed to be plugged into the wall, then you plugged the window unit’s power chord into the control. You put the control’s sensor in the middle of the room and you set it to the desired temperature.

    Luckily for brewers, the control was cheap (around $20), and most importantly, was capable of controlling temps down to 32F (0C), though I always wondered who would ever set their room temp to 32F!

    I had an old fridge in the basement that I plugged into it. I set the control to 33F and put the sensor in the freezer side of the fridge. I did a couple of lagers that way. The lagers weren’t bad, but they never approached the quality of the ales (which I kept at around 60F). I never did figure out what I was doing wrong.

  2. Damian says:

    I’ve not yet attempted a lager but now that I’ve got the ability to drop the temperature down nice and low I might have to give it a go at some stage.

    I put down an ordinary bitter this morning using Styrian Goldings and will try the same again in a fortnight with Fuggles to see the difference. After that I want to try out a porter or two and then perhaps I’ll look into lager.

    Your mention of air-conditioning a room makes sense but you’d want really good insulation but even then the poor thing would have to work pretty hard. I’m happy with the fridge setup at the moment though I’ll need to invest in a heat pad when we come into winter I guess.

    Not tempted to get back into it?

  3. Good choices on the hops for a bitters! Give dry-hopping a shot if you haven’t yet – it’s incredible!!

    I used to do the same thing: I’d repeat a recipe except I would change just one of the ingredients. Only I did it less with hops and more with the grains to see what flavor each type of grain imparts. I do miss brewing – I kept all the equipment in hopes that I would get back to it one day. It may be sooner than later – your enthusiasm is damned contagious! :D The next 2 weekends are definitely out – I have a project due the end of this month and I want to make sure I keep well ahead of the deadline (which probably means weekend work). But after Feb, I might just dust off the old brew kettle and give it a go! If I do, I’ll probably try an IPA.

    The Hunter device was manufactured for use with room air conditioners, but brewers who used the device hooked it up to the fridge, not a room unit.

  4. Damian says:

    If you listen to podcasts I can recommend Brew Strong (RSS) for in depth discussion on aspects of brewing and The Jamil Show (RSS) for specific beer styles and recipes.

  5. Good links! Didn’t even know anything like that was out there.

  6. Brett says:

    This is one of the reasons we are reticent to try home brewing a lager; temperature control. The basement in Ohio this time of year is fairly consistent around 50 degrees but with spring on the way, that won’t last long. We need to spring for a dedicated fridge or rig one up like you did here.

  7. Damian says:

    I’ve done four batches in the fridge so far and have noticed a cleaner, less-estery taste. Well worth the money and you don’t need an expensive fridge. See if you can find one with a broken thermostat as you will probably want to bypass it anyway once you have your temperature controller.

  8. Trev says:

    I just got myself a Tempmate and was looking for a bit more guidance around wiring it up. I like what you did with the box and will study the picture you included. I also wondered what the “melbournebrewers” had to say but unfortunately the link you gave is dead. Did you save that information anywhere? Any other sage advice to impart given the benefit of hindsight?

  9. Damian says:

    Hi Trev and thanks for alerting me to the broken link over at melbournebrewers. I’ve managed to find the article again and have fixed the link. Take a look; they’ve done a good job of describing how to set it up.

    The only sage advice I have is that everyone who brews should have a temperature controlled fridge!

    Friends of mine have recently bought cheaper versions of the Tempmate and they seem quite happy with them so, if you’ve not got around to purchasing yet and if you’re interested in saving a bit of money, let me know and I’ll find out more details. I think it might have been half what I paid. (I just re-read your comment and see that you’ve already purchased)

Leave a Reply