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Nuwave2 Precision Induction Cooktop
Nuwave2 Precision Induction Cooktop

Homebrewing inside using Induction stoves

Arctic Vortex

Winter in the northern states of the USA, most of Canada, and parts of Europe usually means there are certain days in January and February where it is not possible to brew outside, or in a detached garage, due to the freezing temperatures. Even if the tap or faucet is not frozen then unless you have relatively warm ground water the hose pipe will often eventually slow to a trickle as it freezes due to cold water running through a pipe with very cold outside temperatures.

Arctic Vortex freezing temperatures
Arctic Vortex freezing temperatures

Last winter we had this happen to us, we managed to get the brewing finished but during cleanup the hose pipe turned into a 50 foot length of frozen pipe. Luckily we had finished the mashing, boiling and chilling of the final wort! It just meant cleanup had to take place a couple of days later. So after this we decided ah well there will be a few days we cannot brew so providing we watch the weather forecast we should be able to plan yeast starters and brew days accordingly

Enter Winter 2013/2014 which started off very cold in December rather than January… that was until the Arctic Vortex gave us temperatures including wind chill of -30F or -34C so brew days outside or in the garage were not even worth considering.

Alternative Solutions

During a recent local club meeting a fellow homebrewer showed us his system which included the use of Induction Stoves for heating the water in the HLT (Hot Liquor Tank) and also the Mash Tun but he did state that the final boil for the 5 gallon batches was still done outside using propane.

Nuwave2 Precision Induction Cooktop (PIC)
Nuwave2 Precision Induction Cooktop (PIC)

Note: For those who are new to homebrewing please be aware that propane burners should not be used inside due to the Carbon Monoxide that is given off and that plenty of ventilation is needed.

After considering our inability to brew outside I started to research the price and options for Induction Stoves and found that the Nuwave2 Precision Induction Cooker (PIC) could be purchased at Bed, Bath & Beyond for $99.99 but if you signed up for their newsletter then you could get a 20% coupon off any one item. The Nuwave2 can also be bought on Amazon for around $95 – see here.

So we both signed up for the coupon and decided to go and buy two of these Induction Stoves. One for heating the sparge water in the HLT and at the same time use the other for heating the Mash Tun. The aim was then to replace the HLT with the Boil Kettle once the sparging was complete.

False bottom inside Mash Tun
False bottom inside Mash Tun

Equipment

The various valve and false bottom fittings were removed from our 3-tier system then after being cleaned we dug out our old 2 x 8 gallon stainless steel pots that we used to use when brewing 5 gallon batches inside on the kitchen stove. One of these pots was converted into a Mash Tun with a valve linked to a false bottom which is a domed disc of stainless steel metal with perforated holes and a tube coming up through the center to the ball valve. The false bottom helps raise the bed of grain off the bottom of the Mash Tun so that clear liquid can pass out through the valve.

Side pickup & valve inside Boil Kettle
Side pickup & valve inside Boil Kettle

The other pot was converted into a Boil Kettle with a 90 degree tube to pickup the wort from the side of the kettle and take it out through the ball valve hence avoiding the sediment in the middle of the pot which is accumulated after chilling the wort by swirling it around and allowing time for it to settle.

For an HLT we also had a 5.5 gallon stainless steel pot in mind for that task.

The Induction Stoves were both 1300W and had 10 degree F increments from 100F up to 575F. Induction Stoves work by creating magnetic fields that heat up the metal pan rather than heating the surface of the stove that then heats the pan.

Note: Aluminum or porcelain pots will not work with Induction Stoves, the pot must be magnetic and can easily be tested by using a magnet – if it sticks it will work, if not then it will not.

Brew time

Mash Tun on Induction Stove
Mash Tun on Induction Stove

So the brewing process began with measuring out the batch sparge water in the HLT and heating that up on full (Sear setting) with the lid on. The grain for our Scottish Export 80/- was weighed and ground using our mill whilst the strike water in the Mash Tun was being heated up using the Medium-High setting of around 325F.

Once the strike water reached 164F the grain was added but with the grain itself being so cold it took the mash water down to 138F which was below the 154F mash temperature suggested in Jamil Zainasheff’s book, Brewing Classic Styles, from which the recipe was taken. This then required turning on the stove to heat it back up whilst stirring to avoid hot spots.

The problems begin

All went well with the mashing until it came to sparge time… the HLT was taking forever to reach the 170F for approx 4.5 gals and then the kettle in the kitchen was turned on upstairs thus tripping the fuse box and not for the first time that day. A few times both Induction Stoves would go beep and turn themselves off for no reason – overheating?

Hot Liquor Tank (HLT) on Induction Stove
Hot Liquor Tank (HLT) on Induction Stove

The conversion of the mash completed which was indicated by performing a starch test on some of the wort – when complete the color of the iodine does not change but when incomplete (i.e. some starch still remains) then parts show up as black or dark purple.

The valve of the Mash Tun was connected to the Boil Kettle via a tube and the first gallon was captured in a jug and placed back into the mash to allow the grain bed to set and act as a filter – this is called ‘vorlauf’ from the German word for wort recirculation.

After run-off the batch sparge water from the HLT was poured into the Mash Tun and stirred then sparging, including vorlauf, began again.

After finding out how long it took to heat the HLT to 170F we soon figured that bringing 7+ gallons to the boil in one pot would not work so the wort was split between the Boil Kettle and the HLT.

Wort struggling to boil in kettle
Wort struggling to boil in kettle

Bringing both to the boil took forever especially compared to the 150,000 BTU burners used in our 3-tier system which can bring 12 gallons from 160F to boiling in about 20 minutes. These 2 x 3.5 gallons took a good 1+ hours…!

Once they reached boiling the various hop additions were added but another problem encountered was that the lids could not be left off in order to drive off unwanted components such as DMS (Dimethyl Sulfide) as this caused the wort to stop boiling. These unwanted components can cause off-flavors in the final beer so a vigorous boil is needed with the lid off. The only way to counter this was to leave the lids on until boiling then partly take them off – not ideal! Another side effect is that normal evaporation did not take place which meant that the post-boil gravity was lower than ideal but was still within style. The target starting gravity was 1.053 and the actual gravity was 1.049.

End of brew day

Transferring wort to Primary Fermenter
Transferring wort to Primary Fermenter

Eventually the boil was completed and the worts were combined into the larger Boil Kettle so that the copper coil chiller could be used then the whirlpool created to gather the sediment in the middle.

Once the wort was run-off into the primary fermenter it was then oxygenated, yeast nutrient was added then the yeast starter was pitched. Last night the primary was siphoned into the secondary fermenter and so far it has reached a gravity of 1.016 and tastes fine. The beer will sit in the secondary for another week and will hopefully reach 1.012 before being ready for bottling.

Fermentation has taken place at 66F using a temperature controlled freezer using a Reptile Tank Heating Mat – see here for more details and visit the post from Jan 11, 2014, on our Facebook page for how it is used in our setup.

Verdict

So what is our verdict on using Induction Stoves for homebrewing during winter or as an indoor solution?

Yes it is a feasible option BUT it lengthened the brew day from 4-5 hours to around 7 in total. Sure it was nice being warm inside but it was a lot of effort to produce 5 gallons when less time and effort outside would have allowed us to brew 10 gallons.

Oxygenating wort ready for fermentation to begin
Oxygenating wort ready for fermentation to begin

We thought that control of temperatures would have been better with the heat being instantaneous and easier to fine tune compared to the powerful propane burners but the reality was that it was too easy for the temperature to drop off and then took forever to heat back up.

The boiling problem could have been overcome by doing that part of the process outside like my fellow home brewer does but the problem with that is carrying 7 gallons of 160F wort upstairs from the basement and outside – I figure it is only a matter of time before a stumble would result in injury and/or hot sticky wort everywhere.

We ended up returning the Induction Stoves for a refund and going forward will investigate other options such as insulating water pipes out to the garage and going back to choosing days where the temperatures are above freezing.

If you have any comments on this article or suggestions regarding how to overcome the problems of brewing in freezing temperatures then please let us know by leaving a comment below?

One comment

  1. You could do something simple as splitting your batch into two kettles post-boil, half into a four or five gallon pot, and safely transport the wort that way.

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