Download THE WILLIAMSWARN BREWMASTER USER MANUAL
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increase the pressure back to close to 1.25 bar. You will do that again after a 1 day waiting period. differential of 0.25 -0.5 bar is required between the vessel (at the lower pressure) and the gas cylinder (at the higher pressure) in order to force the clarification agent in when the 3-way valve is turned to the clarification pot. After clarification the vessel will therefore be near the dispense pressure that the gas cylinder is set at and you can connect the gas cylinder to the vessel by opening the 3-way valve. You will then wait 1 ½ more days for a final clearing and then begin to consume the fully carbonated beverage. MONITORING THE PRESSURE IN STEP 3 AND ADJUSTING THE VPRV SET-POINT. When you brew, you will need to use the pressure in the tank during fermentation to set the VPRV at the pressure you desire. We have used a 0.5 bar pressure differential for clarification to be sure first time users clear their beers, but this can be reduced to 0.25 bar and clarification also achieved. Any pressure differential less than this will likely not mix the clarification agent well enough into the beer. Winding the screw down (clockwise) will increase the vessel pressure required to release the spring and winding it out (anti-clockwise) will lower the vessel pressure required to release the spring. Note: We describe two methods on how to release the pressure during a clarification. In the main instruction we use a method for beginners where they carefully create the pressure differential before opening the 3-way valve. In Appendix 8 we describe another method that experienced brewers may like to try, where they turn the 3-way valve and then release the pressure and control clarification by the amount of bubbling that is heard. This method requires experience with regards to knowing the amount of vigorous bubbling that is heard (for adequate mixing) and what a successful clarification process is. See Appendix 8 for details. To test any new setting the vessel will need to be pressurised and the vessel pressure gauge read when the sound of gas emitting from the VPRV is heard. This can be done at any time by adding gas from the gas cylinder to the vessel. However it is easiest and results in less loss of bottle gas if performed during fermentation when the yeast is making excess CO2. PRESSURE CONTROL FOR LOW CARBONATED BEERS When you brew beers at a very low carbonation level, another clarification technique is required. This is because the pressure is so low, we cannot release gas from the vessel via the VPRV lower than atmospheric pressure (0 bar) and so the first clarification method described above cannot work. For example, if you’re making an English Ale at 5°C and want a carbon dioxide content of 3 g/l, you only need 0.12 bar pressure in the vessel, which is very low. So you cannot release 0.25-0.5 bar out of the vessel as described in the first method when making well carbonated beers. If the vessel pressure is below or above the set-point, the VPRV needs to be adjusted. It is important the pressure be near the target (e.g. 1.5 bar for first time users). You don’t need to be 100% accurate as we’re fermenting at a level slightly higher than we actually need but get as close to this as possible. Excess gas will be released manually during the clarification phase. The yeast makes it for free and we are in fact keeping about only 10% of what the produce, so it’s no issue to ferment at a higher pressure and release later. So for your first brew, set the VPRV at 2 ½ turns counterclockwise for fermentation. This is approximately the release point of 1.5 bar. During the first day (for ales and 2nd day for lagers) the pressure will build up and you can adjust the setting. Therefore, during fermentation, if the pressure in the vessel is too high above target, unscrew the VPRV slightly (anti-clockwise) until gas is heard to be emitted at the desired set-point. In this case you need to brew with the VPRV set at about 0.25 bar above the level of carbonation you want (to allow for the drop in pressure when the cooling is put on) and set the gas cylinder at 0.5 bar above that (to create the pressure differential). Then clarify as per normal and the gas bottle pressure will force the clarification agent in the beer. The pressure will increase in the vessel and it should release itself out of the VPRV. When you’ve finished clarifying, you then should release pressure out of the VPRV to the level you want in the final beer. If the VPRV is releasing below target (as heard and smelt off the VPRV and read on the vessel pressure gauge), then you need to wind the VPRV down a bit (clockwise) and let the pressure build up and then adjust further. If you want to set it there and then without waiting, you’ll need to add some gas from the gas cylinder to the fermenting brew in the vessel by turning the 3-way valve to the vessel and adding e.g. 0.3 bar pressure above the target as read on the vessel pressure gauge and then close the 3-way again. Then unscrew the VPRV anticlockwise until gas is heard to be emitted at the desired set-point. You will clarify a second time using the same principle. Once you have finished the second clarification, release the increased gas in the vessel again to the pressure (and therefore carbonation level) you want. Then after this, you will finally set the gas cylinder at the same pressure which is your chosen dispense pressure, and open the 3-way valve to the vessel. When you dump the sediment bottle after 36 hours, the beer will be at the correct pressure and carbonation. After a few brews you will know where to set your VPRV for any desired target but you’ll likely always need some fine-tuning in the first few days of any fermentation. THE VPRV DURING DISPENSE When the vessel is being dispensed, it is best to have the VPRV at maximum to keep its release point as far away from the gas cylinder setting as possible. So set it at maximum pressure during dispense by screwing it right down (clockwise). When fully wound down it will release at 2.2 – 2.5 bar, depending on the spring tension and ambient temperature. If the VPRV is set too close to the gas cylinder pressure during dispense, a small amount of gas from the gas cylinder may emit out the VPRV which is a waste of good carbon dioxide. The difference with this method is that you cannot set the gas cylinder at the pressure you want in the final beer during dispense until after you have clarified. With higher carbonated beers as described in the first method above, you can set the gas cylinder pressure at the beginning of the process and not change it and use the VPRV to make the pressure differential by releasing pressure from the tank. In either case the principle is the same in that a pressure 57