DrainPro Mash Tun — Bottom-Drain Brewing Vessel
Product · DrainPro brew kettles

DrainPro Mash Tun — Bottom-Drain Brewing Vessel

Sloped-bottom mash tun with false bottom and welded recirc ports.

Est. 2014
304 stainless · TIG-welded · mirror polished · sanitary 1.5" tri-clamp throughout · in stock, ships from Vancouver, BC in 1–2 days · 2-year warranty + lifetime parts.

Designed around the drain. Welded 1.5" tri-clamp outlet, sloped geometry that pulls every drop, fine-perforated false bottom that traps the grain bed over a clean exit. Recirculation supply + return ports at the side. 304 stainless, TIG-welded, mirror polished inside and out.


A standalone mash tun built to drop into any tri-clamp brewhouse. Sized 10G / 20G / 30G / 50G. 20G and larger ship with a hinged side grain door for top-down cleanup at scale. Sanitary 1.5" tri-clamp throughout — the same standard used in commercial breweries.


For brewers building a three-vessel hot side from scratch, replacing a leaking mash vessel, or scaling up one vessel at a time. Designed and assembled in Vancouver, BC. Tariff-free worldwide.

Step 1 — Choose your size 10g
$529.00 USDShips from Vancouver, BC
Add $71 more to unlock free continental US shipping Duties, tariffs & brokerage prepaid on every order — shipping is the only thing left to unlock.
or $132.25 USD
with Shop Pay Installments
Ready to ship · most orders out in under a week
2y
2-year warranty · lifetime parts · every part replaceable
Talk to a brewer, not a sales rep · email or call — real humans
Step 1 — Configuration

Vessel only, or vessel + recirc kit?

Vessel only is the bare welded mash tun — for brewers replacing or expanding a hot side who already own the plumbing. Recirculation Kit adds the hardware to make it brew-ready out of the box.

How the Mash Tun works

Six steps. Bottom drain through every one.

A complete brew-day workflow — dough-in through CIP. The bottom drain stays in play across every step, so there's no tilting, no pickup tube to fight, and no dead spots where wort gets left behind.

Step 1

Mash in — dough in over the false bottom

Strike water from the HLT lands on top of the grain bed through the recirculation supply port. False bottom traps the grain; the mash sets up over a clean slope.

Step 2

Recirculate — continuous step mash

Pump pulls wort from the bottom drain, returns to the top through the recirc port. Run a programmed step mash without tilting or interrupted flow.

Step 3

Vorlauf — clarify the wort

Slow the recirculation, let the grain bed filter the wort clean. Watch the sight glass on the return arm — break transfer when it runs bright.

Step 4

Sparge — drain to boil kettle

Hot sparge water from the HLT enters the top while wort drains out the bottom into the Boil Kettle below. Bottom drain pulls a complete transfer with no left-behind volume.

Step 5

Grain out — open the side door (15G+)

Hinged grain access door swings open. Shovel spent grain out the side; rinse the false bottom with the lid spray ball. No lifting a 60-pound grain basket out of a hot vessel.

Step 6

CIP — spray + drain

Spray ball through the lid TC port pulses caustic, acid, and rinse through the vessel. Bottom drain returns to the CIP pump. Closed-loop wash, no manual scrub.

What's included

Mash tun, false bottom, every port welded in.

Hinged side grain door ships standard on 15G and larger. 10G ships without the grain door; spent grain is removed via the false bottom at that scale.

DrainPro Mash Tun — vessel only
  • TIG-welded mash tun — 304 stainless Fully TIG-welded, thickest walls in the industry (1.2 mm on 10G/15G/20G, 1.5 mm on 30G/50G). Mirror polished inside and out. Sloped bottom carries every last drop to the drain port — no tilting, no dead volume.
  • Pressed stainless false bottom Fine-perforated, sized to the vessel. Sits above the welded drain; pulls a clean wort transfer through the grain bed without channeling.
  • 1.5" TC bottom drain port Welded at the low point of the sloped bottom and brought forward in line with the side ports. No threads, no leak points, no pickup tube. Valve not included — it’s in the Recirculation Kit.
  • 1.5" TC recirculation supply + return ports Side-mounted welded TC ports for the pump loop — supply on bottom, return on top. Drives recirculation and sparge in continuous flow.
  • CIP port in the lid — included Welded tri-clamp port in the lid for a spray ball or steam condenser. Ready for closed-loop CIP without opening the vessel.
  • Grain access door (15G, 20G, 30G, 50G) Size-dependent Hinged, welded side door. Swings open for shovel-out grain removal. Ships standard on 15G and larger; 10G does not include a grain door.
  • Etched internal volume markings Stamped right into the interior wall. Read in US gallons and litres. No floating ruler to lose.

*Grain door ships standard on 15G and larger. Pricing assumes vessel-only build; Recirculation Kit priced separately.

Technical specifications

Specs by size.

Specs for:
Volume · dimensions

10 US gal (38 L) · 35 cm (13.8") Ø × 40 cm (15.7") H

Recommended batch

~5 gallons finished beer

Material

304 stainless · fully TIG-welded · mirror polished inside & out

Wall thickness

1.2 mm · thickest in industry at this size

Bottom drain

1.5" TC from the sloped bottom, brought forward in line with the side ports · valve in Recirculation Kit

Recirc ports

1.5" TC supply + return · side-mount

Grain door

Not included at 10G — ships standard on 15G and larger

Pairs with

Any 10G boil kettle · BräuPro 5G hot side

US
Free US shipping over $600Continental US · duties, tariffs & brokerage prepaid
2y
2-year warranty · lifetime partsEvery part replaceable
14
Hand-built in Vancouver, BCSince 2014 · we invented the single-vessel electric brewhouse
Talk to a brewer, not a sales repReal humans · email or call
Build the rest of the hot side

More DrainPro vessels.

Same architecture, same fittings, same drain. Stack the Mash Tun with the matching Boil Kettle (and HLT for a full HERMS) — they share clamps and gaskets across every size.

Common questions

About the DrainPro Mash Tun.

I'm in the US — will I get hit with tariffs, duties, or brokerage fees?+

No. Every price on this site includes free continental US shipping, and we prepay all duties, tariffs, and brokerage on your behalf. You won't get a courier collect-on-delivery for surprise import fees days after your order lands. The price you see is what you pay. (Alaska, Hawaii, and international freight — contact us for a quote.)

Which size should I buy?+

10G for 5-gallon batches. 15G for 7–8 gallon batches — first size with the hinged grain door. 20G for 10-gallon batches and larger grain bills. 30G for 20-gallon double batches or pilot capacity. 50G for ~1 BBL pilot operations or taprooms running back-to-back brews. Architecture and fittings are constant across the line.

Why does the grain door only come on 15G and larger?+

The grain door is too large to fit cleanly on the 10G vessel — at that scale the side panel can't accommodate it. From 15G up, the door is sized correctly and gives you waist-height shovel-out instead of lifting spent grain over the top of the kettle.

Can I specify a custom size?+

Yes. For volumes outside the standard 10G/15G/20G/30G/50G ladder, contact us with your spec and we'll quote a custom build. Lead time is around 3 months on custom work.

Why is the bottom drain welded rather than a removable TC?+

Welded is cleaner. The single continuous pipe from vessel floor to butterfly valve has no joint, no gasket, no crevice where grain husks or yeast can lodge. It's also faster to clean — one straight bore, no fitting to disassemble. Removing the drain isn't necessary for any normal service or CIP, so the weld is the simpler, cleaner build.

Is this just for HERMS, or works for RIMS too?+

Either. The recirculation supply + return ports are TC and pump-agnostic — drive them with an external HERMS coil in your HLT, or wire a RIMS tube inline. The vessel doesn't care which method you use; both pull wort from the bottom drain and return through the top.

Can I use it with my existing brewhouse?+

Yes — it's a standalone vessel. If your existing brewhouse uses tri-clamp fittings, you're plug-and-play. If it runs on threaded NPT, you'll need a small adapter kit (TC-to-NPT 1.5"); we can include those at checkout. Pairs cleanly with any size DrainPro Boil Kettle or with a kettle you already own.

What's the difference between Vessel only and Recirculation Kit?+

Vessel only is the bare welded mash tun + false bottom + every TC port welded in — for brewers who already own valves, clamps, and plumbing. Recirculation Kit adds the hardware to plumb the vessel into a HERMS or RIMS loop: 1.5" TC butterfly valve for the bottom drain, double-clamp barb 90° recirc arm with silicone tubing, TC caps for unused ports, full clamp + gasket kit. Brew pump is sold separately — one pump can move between vessels in a multi-vessel hot side.

What ships, and when?+

Ships from our Vancouver, BC workshop. Most orders out in 5–10 days, free continental US shipping. 10G, 15G and 20G ship via standard courier; 30G and 50G ship LTL freight (palletized, with tracking and a delivery appointment).

What's the warranty?+

2-year warranty on every weld and TC port, the false bottom, the grain-door hinges (15G and larger), and the Recirculation Kit valve (when bundled). Gaskets, clamps and O-rings are consumables; replacements are in stock and cheap. Lifetime parts support on everything we build — serviced, not replaced.

Still have questions? Talk to a brewer, not a sales rep. Email or call us during US business hours.

The drain is
the difference.

Sloped-bottom mash tun. False bottom, welded recirc ports, hinged grain door on 15G and larger. Designed and assembled in Vancouver, BC. 2-year warranty + lifetime parts support.