The Cast Air ADVSM is the complete automatic tank drain solution for shop compressors in the 1–10 HP range. At $154.00, it includes the air-operated drain valve plus the full installation kit — strainer, shut-off valve, and all mounting hardware. If you want to stop manually draining your tank and do it right the first time, this is the kit to order. You get everything you need in one part number, no separate hardware runs, no guessing on fittings.
Moisture in a compressor tank is a slow disaster. Every time hot compressed air enters the tank, it cools, and water vapor condenses out. In a working shop — especially in a humid climate — a 60 to 80 gallon tank can collect a cup or more of water per day. That water sits at the bottom of the tank, corroding the steel from the inside. It gets picked up by the air stream and pushed downstream into your tools, spray guns, and airlines. It ruins paint jobs, causes rust in airline fittings, and shortens the life of every air-powered tool in the shop. The ADVSM eliminates that problem automatically, without any electrical wiring, without any timers, and without anyone remembering to open a petcock at the end of the day.
How the Air-Operated Drain Works
The ADVSM uses the compressor's own air pressure to actuate the drain cycle — no external power source required. The valve is set up so that when the compressor unloads (pressure drops at the end of a cycle), the differential pressure across the valve actuates a drain purge. Condensate that has settled at the bottom of the tank gets expelled before the compressor reloads. This timing is ideal: draining at the unload point, when condensate has had time to settle and before it gets stirred back up into the air stream.
Because it is air-operated rather than electrically operated, you have no solenoids to burn out, no 120V wiring to run to the compressor, and no timer batteries to replace. The valve responds to the compressor's actual cycle, not a fixed time interval — which means it drains when draining is needed, not on a schedule that may or may not match your shop's actual run time.
What the ADVSM Includes (Complete Kit)
The ADVSM is the complete installation package. The ADVS valve is available separately at $119.43 if you already have the hardware, but the ADVSM gives you everything needed for a clean, professional installation:
- ADVS Air-Operated Drain Valve: The core valve unit, rated for 1–10 HP compressors
- Strainer: Protects the valve seat from debris and scale that can come off the inside of an older tank — critical for long valve life
- Shut-Off Valve: Allows you to isolate and service the drain assembly without fully depressurizing the tank
- Mounting Hardware: All fittings and hardware needed to complete the installation
Key Features
- Air-Operated Actuation: Uses compressor pressure differential to open drain — no electrical connection required, no 120V wiring needed
- Cycle-Timed Draining: Valve purges at the compressor unload point, the correct moment to drain settled condensate
- Complete Installation Kit: Includes strainer, shut-off valve, and all mounting hardware — nothing additional to source
- 1–10 HP Rated: Sized for the most common range of single-phase and small three-phase shop compressors
- No Solenoids or Electronics: Purely pneumatic mechanism — nothing to burn out, nothing to wire, no timer to program
- Strainer Included: Protects valve seat from tank scale and debris that would otherwise cause premature failure
- Shut-Off Valve Included: Allows servicing the drain assembly without a full tank depressurization
- Cast Air Construction: Minnesota-made, built to the same quality standard as the Castair compressor line
Benefits: What This Actually Does for Your Shop
- Extends Tank Life: Eliminating standing condensate stops the internal rust that eventually requires tank replacement or fails inspection
- Drier Air Downstream: Less moisture reaching tools, airlines, and spray equipment means longer service life and better spray results
- Eliminates a Maintenance Step: One less thing on the daily or weekly maintenance checklist that actually gets skipped in a busy shop
- No Surprise Failures: Automatic draining means the job gets done every cycle, not just when someone remembers
- Pays for Itself: The cost of one moisture-contaminated paint job, one rusted-out tank, or one set of air tool repairs exceeds the cost of this kit many times over
What's in the Box
- 1x Cast Air ADVS air-operated drain valve
- 1x Inline strainer (protects valve from tank debris)
- 1x Shut-off valve (for service isolation)
- All mounting hardware for complete installation
Available Configurations
Cast Air offers two versions of this air-operated drain system, plus electronic drain options and a manual petcock for reference:
- ADVS — $119.43: Valve only. The same air-operated drain valve without installation hardware. Order this if you already have the strainer and shut-off valve from a previous install, or if you are replacing just the valve.
- ADVSM — $154.00 (this kit): Complete installation kit. Valve plus strainer, shut-off valve, and all mounting hardware. The right choice for a first install or a full replacement.
- SDV03S — Electronic Drain w/Strainer, 115V: Timer-based electronic solenoid drain. Requires 120V wiring. Better choice for very large tanks or continuous-duty industrial compressors where a fixed drain interval is preferred over cycle-based draining.
- SDV03M — Electronic Drain w/Install Kit, 115V: Same electronic solenoid with complete install kit. Full electrical drain solution when you need programmable timer control.
- PC14 — Petcock 1/4": Manual drain. Low cost, no automatic function. For shops where someone will actually open it every day without fail — which in practice means most shops should not rely on this.
When Does a Shop Need the ADVSM vs. Other Drain Options
Choose the ADVSM when:
- You have a 1–10 HP shop compressor and want automatic draining without any electrical work
- Your compressor is in a location where running 120V to the drain valve is inconvenient or impractical
- You want a complete kit with no additional hardware to source — one part number, everything included
- You want draining tied to the actual compressor cycle rather than a fixed timer interval
Step up to an electronic drain (SDV03S or SDV03M) when:
- Your compressor is larger than 10 HP and runs more continuously — where a cycle-based pneumatic drain may not purge frequently enough
- You want precise programmable drain intervals and a solenoid that is independent of the compressor's unload cycle
- You have 120V easily available at the compressor location and prefer a timer-based system
The manual petcock (PC14) is fine when:
- Budget is the only consideration and someone in the shop will genuinely drain the tank every day without exception
- In practice, this is rarely the right answer in a busy shop environment
Technical Specifications
- Part Number: ADVSM
- Manufacturer: Cast Air (Castair), Minnesota
- Compressor Range: 1–10 HP
- Operation Type: Air-operated (pneumatic actuation, no electricity required)
- Drain Timing: Cycle-based — actuates at compressor unload
- Kit Contents: Drain valve, strainer, shut-off valve, mounting hardware
- Valve Model Included: ADVS
- Price: $154.00
- Country of Origin: USA (Minnesota)
Why Buy From Air Compressor Factory Direct?
Air Compressor Factory Direct has been supplying shops with Cast Air compressors and accessories since 2016. We stock the full Castair accessory line — drain valves, filter bowls, drain kits, and hardware — so you can source everything from one supplier who actually knows the product. When you call us, you talk to someone who can confirm whether the ADVSM fits your specific tank setup, not a call center reading from a spec sheet.
Every Cast Air accessory order ships free. We back every product with the full manufacturer warranty. If you have installation questions or need help choosing between the pneumatic and electronic drain options for your specific compressor, call us directly — we will tell you the honest answer, not just the more expensive one.
Call 866-217-0063 for quick answers and help!
