Immersion is a gentle cooler and heater that lowers and increases the temperature of your beer gradually over the course of a few days. Normal performance in a PET Carboy is 1ºF/hour for the first 10º F below/above ambient, 0.5º F/ hour for the next 10º F below/above ambient, and 0.25º F/ hour for the next 10 to 15º F below/above ambient. Other fermenters can take a little longer to cool or won't get as cool.

• Check your temperature probe position. Probes must be placed at the upper 1/4 of the liquid level. If your fermenter has a thermowell, use that only if it measures from the upper 1/4 of the liquid level.
• Check the ambient temperature of your room. If your room sees large swings in temperature, or generally increasing ambient temperatures, Immersion’s performance will be degraded. Both direct sunlight and lack of ventilation are two common causes of high ambient temperatures.
• Let your jacket equalize in temperature for a few hours before you begin using Immersion. If the jacket is too warm, it will cause a startup lag as Immersion must cool both the wort and the jacket to the same temperature before it can make measurable progress on cooling the beer.
• Make sure the temperature probe is plugged in tightly and is registering the correct temperature. Submerging into an ice bath should yield 33.6ºF / 0.9ºC. If your probe is not reading 33.6ºF / 0.9ºC in an ice bath, follow the instructions below to re-calibrate your probe. Taping your temperature probe to the fermenter in the upper 1/4 of the liquid level will ensure an even measurement.
• Unscrew your rod and make sure nothing is between the cold contact point on the head unit and shiny surface of the rod. Obstructions here will inhibit heat transfer.
• Turn on the unit, set it to cool. Wait between 5 and 10 minutes after the fan turns on and feel the air being released – it should be warm. If it is not warm at all or if it is very hot, contact support@brewjacket.com.
• Make sure the heat exhaust vents aren’t blocked by the jacket.
• Cinch the jacket tightly around the rod. A loose jacket can cause warm air to enter the insulated area and warm up the beer.
• Feel the jacket insulation for gaps, both the around the body and around the base. If the insulation is not uniformly distributed around the fermenter, heat will be able to enter the fermenter.
• More your fermenter to carpet or wood flooring or place a towel or blanket under your fermenter. Fermenting on cement or tile can allow heat to be transferred into the fermenter, hampering performance. Adding ground insulation can help performance.

Immersion works best with 5-6 US gallon liquid volumes in fermenters with a capacity of 8 US gallons (30L) or less. 14 US gallon fermenters require custom insulation and enough liquid volume for the rod to touch the wort. While Immersion can work, performance is not guaranteed. We do not make jackets for 14 gallon fermenters, so insulating it yourself with a minimum of 3″ thick insulation is critically important.

Yes. With less liquid, there will be less submersion of the heat transfer rod, however this is okay since there is simply less liquid to cool. Half sized batches do work, however be aware of that your temperature probe may not read accurately outside of the fermenter and a thermowell may be required.

Immersion only works with fermenters that are 16″ in height or taller. Shorter fermenters with less liquid cause the fermenter to be top heavy and put it at risk of falling over. Therefore many small capacity fermenters are simply too small to function with Immersion. The only 3-gallon fermenter we have found works well is the 3-gallon Better Bottle.

If you believe your Immersion (single display) or Immersion Pro is reading the wrong temperature, follow these steps to set it again:

1. Press BrewJacket logo and + button. Your display will flash. You can press – or + to change the calibrated temperature.
2. Press BrewJacket button to save the calibration.

If you need to revert to factory settings, first change the temp mode to F (press BrewJacket logo and the – button at the same time, press + or – to change to F, then press BrewJacket button again to save).

1. Fill a cup up to the brim with ice then fill then fill the cup with cold water to the top of the ice level.
2. Insert the probe into your ice bath and stir with the probe for 30 seconds, or until the temperature on your head unit stops changing.
3. A factory calibrated head unit will read 33.4°. If your unit does not read 33.4°, calibrate the unit so it reads 33.4°.

• Verify there is a green light on the power supply. If no light, make sure all plugs are securely plugged in and you are using a functioning outlet.
• If there is a green light on your power supply, unplug the head unit and plug back in.
• If no lights return, email support@brewjacket.com

The best way to sanitize your rod without iodine is to simply put it in the boil along with your wort for 30 minutes. Just be sure to unscrew your electronic head unit before doing so. You can also put the rod into the oven at 250º F / 120º C for a period of an hour.

Do not use acid or oxygen based sanitizers on the rod. These sanitizers have extreme pH values that can damage the rod’s finish if allowed to contact for a prolonged period of time.

BrewJacket accepts returns of unopened products for a full refund minus shipping for a period of 30 days after physical receipt of the item. If the item has been opened, a 20% restocking fee will be applied to the refunded amount. We cannot accept returns of used items. Returns will only be accepted if the product was originally purchased through brewjacket.com. If the product was purchased through a reseller, the product must be returned to that reseller. Individual reseller return policies may vary.

To initiate a return, email support@brewjacket.com" href="mailto:support@brewjacket.com" style="margin: 0px; padding: 0px; border: 0px; outline: 0px; background-position: 0px 0px; vertical-align: baseline;">support@brewjacket.com with a copy of your original purchase receipt. Please allow up to 48 hours to process your return.

All BrewJacket products are warranted for a period of 1 year from the date of purchase against manufacturing defects and failures incurred during normal operation. Warranty does not cover abuse or failures resulting from use of the product in ways unintended by BrewJacket, Inc. If your box is missing any components, you must notify us within 30 days of receiving your order otherwise a replacement fee will be assessed.

To initiate a warranty repair, email support@brewjacket.com. Include a copy of your original sales receipt as well as the problem experienced. Please allow up to 48 hours to process your warranty repair.