Building a Better Homebrew Pump

There's nothing more frustrating on brew day than flipping your new shiny magnetic driven pump on and nothing happens. You might have hot water waiting to mash-in or your wort is ready to transfer to the boil kettle, but you can't seem to get anything to move. The pump is on and you can hear it spinning away. What gives? Did you set the pumps up to flow in the right direction? How about position? How about height in relation to your brew kettle or mash tun? Are the pumps self-priming? There's a lot to these little homebrew power pushers and with a few modifications, your pump can be doing double duty.

Bleed Valve and Throttle Assembly
Most affordable home brew pumps on the market are not self-priming, which means that air is the enemy. The pump manufacturers state that "the pumps need to be positioned below the level of liquid for the input in order for the pumps to prime." Speaking from many years of experience with these types of pumps, they don't play nice all the time.

The pump will be full of air and that air needs a place to go. Adding a simple bleed or relief valve can help you release some of the trapped air in the pump chamber. The pump head must be filled with liquid before it will pump properly, so bleeding out the air will allow the pump to get going. It helps to run a tube from your bleed valve down into a bucket or reservoir to catch any small amounts of liquid during pressure relief. The additional outlet also comes in handy for gravity samples during the mash, sparge and final runoff to the fermentor and back flushing your system with cleanser.

Adding a bleed valve to the discharge port allows air pockets out that might be trapped in the pump head. The flow regulating throttle valve is placed on the outlet also. This becomes especially paramount during sparge and transfers that need to be low flow to reduce agitation. It is not recommended to put the throttle valve on the wort in port. This can cause your pump motor stress and possibly a shorter lifespan.

Advanced Two Pump Design
In a two pump all-grain home brew system you have the ability to move all liquid from start to finish using pump power. Below is a sample schematic of a 10 gallon system using two pumps for hot water transfer, mashing in, recirculation, sparge, final runoff transfer through a plate chiller and finally to the fermentor. The pumps, in conjunction with (4) 3-way ball valves, move the entire brew day along without the need to move hoses.

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Hot water flows in from the Hot Liquor Tank (HLT) and is pumped through a 3-way ball valve on PUMP 1 and out to the Mash Lauter Tun (MLT). After the mashing process is completed, the wort is recirculated through the same pump with a twist of the 3-way ball valve on PUMP 1. After recirculation is complete, the sparge process begins. The 3-way valve on PUMP 1 is set back to allow hot water to flow in from the HLT to the MLT's sparge arm/assembly. (Using the Blichmann Auto-Sparge or the Ultimate Sparge Arm can give you even more control over your flow rates.)

The bottom 3-way valve on the MLT is set to divert runoff into PUMP 2 and out to the boil kettle. After the sparge and lautering process winds down and you have boiled your wort, the PUMP 2 bottom valve is switched to allow flow from the boil kettle out to the plate chiller and finally into a closed fermentor. Not only is there no disconnection of hoses in this pump design, but the system remains "closed" during the final transfer to the fermentor. Closed transfers are considered the safest for minimizing exposure of bacteria and wild-yeast.

Pump Position
There are many different ways to design your brewery and the previous example was just one way to go. In that example the pumps would be mounted horizontally to a brewing rig or table below the vessels in order to help pump priming as the manufacturers suggest. The preferred pump head orientation is having the inlet on the bottom and the outlet on the top. Mounting the pump head on its side works too, but make sure the outlet is on the right side and the inlet is on the left. Mounting the pumps in the opposite configurations will cause air pockets and pump cavitation.

In the end, pump head orientation is not something to get hung up on. The pumps should work in any position they are mounted with the use of a bleed valve. Making sure the position of the pump is below the liquid needing to be moved is more important.

Stainless Steel Pump Heads
The pump head material that most non self-priming models come with is Polysulfone (a tough and durable thermoplastic) which has a maximum operating temperature of 250F. A great choice for homebrewing. The stainless steel heads run at the same max out temperatures and are made of food-grade metals that can withstand caustic chemicals. They can be effectively sanitized, so they are more of a professional brewers material of choice and aren't really a necessity for a homebrewer.

They sure are pretty though.

Christian Lavender is a father, husband, computer geek, beer writer and homebrewer in Austin, TX. He currently brews on Picobrew's Zymatic and enjoys styles ranging from hoppy barrel aged barley wine to funky sours. Follow Christian's brewing on

Related Yeast Articles:
Cleaning Pump Heads - Plate chillers, pumps, ball valves, air stones and more.
Different Styles of Mashing - Partial mash, fly sparging vs. batch sparging, infusion, decoction, step, and steeping.
Homebrewing with a Closed Transfer System - Minimizing your wort's contact with air during the brewing process.