The boiler, along with the mash tun are the two basic bits of kit you will need to invest in to progress into all grain brewing, what may seem like a big expense at first soon recoups its value after brewing a few times.
When we brew all grain we ideally want to boil the whole batch of beer, unlike brewing with extract, where you perform a partial boil and then top up the wort to the desired level at the end. Taking the time to mash and extract all the flavour and sugars from grain provides a better quality wort than if you extract only a partial amount and then dilute down with water. This means we need a vessel big enough to accommodate more liquid than the intended batch size.
What Kind Of Home Brew Boiler?
There are various options available to the home brewer and one of the first places to check will be your nearest home brew shop. There are various commercial varieties of boiler available and all will do an admirable job for our purposes. The boilers available are usually around 25 – 30 litres or more which are large enough for a 21 litre or 5 gallon batch. Many of the commercial examples available in the UK are electric boilers with elements in which plug directly into the mains. These boilers will easily achieve a vigorous rolling boil in a short time and often have hop filters in the bottom which allow you to run off a clear wort.
Alternatively if you can get your hands on a large enough catering stock pot you can modify this to your needs. If you are brewing with malt extract or brewing smaller batches you can get by with a stock pot to boil the whole or just part of the batch of beer. At the end of the boil you will be able to top up the wort to the required level. A 12 – 15 litre stock pot is ideal for this kind of brewing. These stock pots are great because they can be placed on the hob in the kitchen which means making beer is as easy as cooking.
If you want to boil bigger batches and brew all grain though you will need a 25 litre pot. To heat this size boiler you will need a burner and gas bottle which means you will need to brew outside but they are a great option which are easily available. Some modifications may be necessary such as making a hole for an outlet tap at the bottom and some brewers even go as far as completely overhauling the pot to add electric elements and sight glasses to measure wort levels. If you do not have these means however there are plenty of brewers who just use a jug to move wort from pot to fermenter so do not worry too much.