Grainfather Brewing Guide: Choosing and Using a Grainfather

Quick answer: the G30 is the natural starting point for standard homebrew batches, the G40 gives you more capacity and a more refined brew-day setup, and the G70 is intended for genuinely large batches. Whichever system you choose, plan the full process — grain preparation, sparging, wort cooling, fermentation and cleaning — rather than buying the brewing unit in isolation.

Which Grainfather brewing system suits you?

Grainfather G30v3

The Grainfather G30v3 is well suited to typical homebrew volumes. It can produce up to approximately 25L of wort, with a 30L vessel and app-connected Bluetooth controller. It is available by itself or as the G30v3 package with counterflow chiller.

• Best for: brewers moving into all-grain brewing, normal homebrew batch sizes and those who want a compact system.
• Cooling choice: choose the package with the counterflow chiller if you do not already own a suitable way to cool and transfer hot wort.
• Connectivity: the controller connects to the Grainfather App through Bluetooth; Wi-Fi bridging is a separate option.

Grainfather G40

The Grainfather G40 is the stronger choice when you want up to approximately 40L of wort, built-in Wi-Fi control, a counterflow chiller and features such as a conical base, integrated sight glass and clean-in-place capability. It also accommodates smaller batches, so increased capacity does not mean every brew must be large.

• Best for: regular all-grain brewers wanting more capacity, faster workflow and room to grow.
• Included cooling: the counterflow wort chiller is supplied with the system.
• Power: the standard setup runs in 10-amp mode. A 15-amp upgrade requires the correct cable and a professionally installed compatible socket.

Grainfather G70v2

The Grainfather G70v2 is designed for large batches, with up to approximately 60L transferred to the fermenter under suitable recipe conditions. Its practical minimum batch size is much higher than the G30 or G40, so it is best chosen because you consistently need volume rather than simply because it is the largest model. Availability can vary.

• Best for: large homebrew batches, group brewing or pilot-scale recipe work.
• Consider first: grain weight, lifting, electrical supply, cleaning space and a fermenter capable of accepting the batch.
• Included cooling: a larger counterflow chiller is supplied.

What you need as well as the brewing system

Required for a complete brew

• A suitable recipe and ingredients: crushed malt, hops, brewing yeast and suitable water.
• A cooling method: required after the boil. The G40 and G70 include a counterflow chiller; choose the relevant G30 package if you need one.
• A suitable fermenter: allow enough headspace for active fermentation, not just the finished beer volume.
• Cleaner and sanitiser: cleaning removes residue; sanitising protects the cooled wort and fermentation equipment.
• Accurate measurement: use the recipe and equipment instructions for volumes, temperatures and gravity checks.

Depends on your setup

• Grain mill: useful if your malt is not already crushed. The crush needs to expose the grain without producing excessive flour.
• Sparge-water vessel: you can heat sparge water separately, or use the 18L Grainfather Sparge Water Heater for a typical G30 setup and the 40L heater for larger requirements.
• Tap adaptors and cooling hoses: confirm they suit the tap and drain locations in your brewing area.
• Suitable power supply: follow the exact requirements for your model and never use an underrated extension lead or adaptor.

Helpful additions

• The Grainfather Graincoat can reduce heat loss around a compatible G30 in cooler conditions.
• A brewing paddle or mash paddle helps with careful dough-in and breaking up dry pockets.
• A hop spider can help contain loose hops, but it must not restrict wort flow or cause the element area to run dry.
• Grainfather High Performance Cleaner is formulated for routine cleaning of compatible brewing equipment.

The Grainfather brew-day process

1. Prepare the recipe and equipment

Load or build the recipe before heating water. Confirm the grain bill, mash schedule, water volumes, hop timings, target fermenter volume and yeast requirements. Assemble the system exactly as shown in the instructions for your model, check valves and filters, and make sure the pump path is clear.

2. Mash and recirculate

Mix the crushed grain into the strike water gradually so there are no dry pockets. Recirculation should be steady rather than forced. A compacted grain bed, very fine crush or fully opened flow can cause overflow, slow drainage or poor temperature distribution.

Step mashing

Step mashing means holding the mash at two or more temperatures rather than using one rest. It can be useful when a recipe calls for a particular fermentability, body or grain treatment, but it is not automatically better for every beer.

1. Enter the complete temperature schedule in the Grainfather App or controller before starting, using the instructions for your model.
2. Treat the recipe temperatures and rest times as part of the recipe; do not add extra rests without a reason.
3. Allow the wort and grain bed time to settle at each target temperature before judging performance.
4. Stir gently if the recipe or system instructions require it, while avoiding damage to the grain basket, plates or temperature probe.
5. After the final rest, continue to the recipe’s mash-out and sparging stages where specified.

3. Lift and sparge

Raise the grain basket carefully and allow it to drain in the supported position. Add prepared sparge water at the rate recommended for the system and recipe. Rushing the sparge can disturb the grain bed, while leaving the basket draining indefinitely can add time without meaningfully improving the batch.

4. Boil and add hops

Bring the wort to a controlled boil and follow the recipe timings. Stay with the system, particularly as the wort approaches boiling. Keep the element area and wort path clear and do not seal the vessel during the boil.

5. Cool and transfer

Use the supplied or selected cooling equipment exactly as instructed. Sanitise every part on the cold side before transferring wort. With a counterflow chiller, check the cooling-water direction and wort connections before starting the pump, then confirm the outlet temperature before sending wort to the fermenter.

6. Ferment

A Grainfather brewing system handles the hot side of the process; it does not replace the fermenter. Pitch suitable yeast at the correct temperature, provide headspace and control fermentation temperature according to the yeast and beer style.

7. Clean promptly

Remove grain and hop debris before it dries. Follow the model instructions for circulating the recommended cleaner through the pump, pipework and chiller, then rinse as directed. Do not immerse electrical parts. Inspect seals, filters, connections and hoses before the next brew.

Common Grainfather problems

• Slow or stopped recirculation: reduce the flow, check the grain crush and confirm that filters and pipework are not blocked.
• Low efficiency: check crush, dough-in, water calculations, mash temperature, sparge method and whether the final volume was measured accurately.
• Scorching or burnt residue: stop and investigate rather than continuing to heat. Excess flour, settled material, restricted circulation or an inadequately cleaned base may contribute.
• Cooling takes too long: confirm hose direction, cooling-water temperature, wort flow and that the chiller is clean internally.
• Transfer slows after a hop-heavy boil: check the hop filter and pump path; do not dismantle hot or pressurised equipment.

G30 video walkthrough

These Grainfather videos show the established G30 workflow. Exact parts and controller screens can differ between generations, so use them alongside the current instructions supplied with your system.

Assembly

Mashing

Sparging

Boiling

Cooling

Cleaning

Brewing-system safety

Hot wort, steam, electricity and heavy wet grain all require care. Brew on a stable, heat-resistant surface with ventilation and safe access to water and drainage. Keep electrical connections dry, do not move a full hot unit, use the basket supports exactly as intended and follow the current manufacturer instructions for your model.

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Ready to compare the options? Browse the Grainfather range, compare the G30v3 with counterflow chiller and the G40, or ask us about matching a system to your normal batch size.