Grainfather Conical Fermenter FAQs

CONICAL FERMENTER FAQ

Q: Can I do smaller batches than 30 L (8 US Gal) and still expect efficient heating/cooling?

A. When heating the contents of the fermenter, this will work with any amount of liquid as it heats from the bottom. Anything below 19 L (5 US Gal) for cooling won’t be as effective.

Q. How accurately does the wall mounted thermometer represent the temperature inside the fermenter?

A. The thermometer accurately reads the temperature at the top of the cone. This is also where the heating unit is located, so when heating the contents of the fermenter, the thermal circulation will keep the temperature fairly even.

Q. How does heating work in the fermenter?

A. In the cavity of the fermenter between the outer body and cone sits a 30 Watt 12V heating element. Unlike standard heating element/sources that directly heat liquid, this is designed to heat the environment in between the walls of the fermenter, which in turn heats the liquid. It is similar to controlling the temperature in a temperature controlled room. This way, the beer is not heating at a single small point, it is evenly and ‘calmly’ heated.

Q. Why does the temperature of the fermenter rise above my target temperature in the first few days of fermentation?

A. When your ambient temperature is lower than your target temperature, you’ll want to use the heating unit to raise the temperature to meet your target. During the active stage of fermentation (exothermic reaction with the yeast), the temperature can rise by a few degrees. This is a common occurrence and doesn’t generally affect the beer but if you are worried you could try setting the target a few degrees lower. Alternatively, for accurate temperature control throughout the whole fermentation process, you can hook the fermenter up to the Cooling Pump Kit.

Q. What volume measurement markings are visible in the fermenter?

A. The measurements are in both L and US Gal, 15 L up to 25 L and 4 US Gal up to 7 US Gal.

Q. What products can I use to clean my fermenter?

A. Any fermenter sanitiser will be fine. The fermenter is all stainless steel so as long as it is rinsed properly there won’t be any issues.

Q. My beer keeps getting infected - what can I do?

A. Using stainless steel minimises the risk of infection but you must continue to use good sanitary practices throughout your brewing. If using the dual valve tap make sure this is cleaned between brews too.

Q. Can I bottle directly from my fermenter?

A. Yes. As with most fermenters if you do not have C02 to push the beer out you will need to lift the fermenter higher. Connect a tube to the sample valve which can be opened and closed. Then fill the bottle with this tube.

Q. I am struggling to harvest the yeast from my fermenter because my yeast dump valve is blocked. What do I do?

A. In this instance it is likely you are not removing the yeast soon enough in the process. After primary fermentation is complete you should leave it no longer than 2 days before harvesting your yeast. Dumping your yeast regularly will also help with this.

Q. Is there a risk of oxygen contamination after dumping the trub or dry hopping?

A. Though there is always some risk of oxygen contamination associated with these stages, it is very minimal. When you disrupt the beer in this manner, some dissolved CO2 is likely to escape which will force the oxygen out of the fermenter and a small amount of oxygen can be absorbed by the yeast during active fermentation. As with any fermenter you should be careful to minimize oxygen pick up as much as possible once fermentation has begun.

Q. Does the Grainfather Conical Fermenter have a racking arm?

A. Yes. The dual valve tap has an arm that extends above the yeast and hops to collect a clear sample.

Q. What is the coldest temperature the Grainfather Conical Fermenter can reach?

A. 4oC (39oF) with beer.

Q. What is the height from the bottom ferrule to the floor?

A. 165 mm (6.5”)

Q. When using the Dual Valve Tap, is there enough room to take a sample and dump the yeast?

A. Yes, to dump your yeast, you will need something similar to a 500 ml (16.9 fl oz.) beaker for collection. If you use something larger to collect your yeast in, you will need 19 mm (0.75”) (internal diameter) tubing for collection. You can take a sample for a refractometer reading from the sample outlet but if you would like to take a sample big enough for a hydrometer reading, you will need a 10 mm (0.39”) (internal diameter) tubing to attached to the sample outlet.

Q. Can I use a blowoff tube with the Grainfather Conical Fermenter ? If yes, how do I set this up?

A. You will need a fitting that can connect the blow off tube to the 38 mm (1.5” ferrule). We don’t sell this.

Q. Does the Grainfather Conical Fermenter come with the temperature controller as standard?

A. No, the temperature controller is an optional extra. You can still heat the contents of your fermenter though. Simply plug the fermenter in directly and allow the temperature to rise. The temperature will rise approx 1°C per hour. When your target temperature is reached, unplug the system. This temperature will be maintained for several hours.

Q. Can I add fruit/other adjuncts directly to my fermenter?

A. It is fine to add adjuncts to your beer in the fermenter. To make cleaning easier and avoid any risks of clogging valves it is best to add these adjuncts in a sanitised nylon hop bag.

Q. I am getting a metallic off-taste in my beer, can this be caused by the fermenter?

A. If you have followed the cleaning instructions this will not be due to the fermenter. Stainless steel does not impart metallic flavours. This is most likely an issue with your wort or yeast.

Q. How does cooling work?

A. To be able to cool you need theCooling Connection Kit which is sold separately. In between the two stainless steel walls of the fermenter sits a cooling sleeve (also made of stainless steel). This cooling sleeve is welded onto the inner wall of the fermenter. The cooling sleeve has two holes on each side. The lower one is where a coupler is connected; this is the entry for the cooling liquid. The upper hole is where the cooling liquid exits. As the cooling liquid travels through this sleeve, it cools the stainless steel which in turn cools the wort/beer in the fermenter. This cooling sleeve never comes into contact with the wort/beer and is never seen by the user. This means that it is not something that needs to be cleaned or sanitised.


You will need the fermenter Cooling Connection Kit to connect the Conical Fermenter to the cold water.

This kit includes:

- 2x couplers (self sealing hose connections)

- 2x 2 m (6.6 ft) hoses

- 2x hose clamps


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