The Cast Air ADVS is an air-operated automatic tank drain valve for shop compressors in the 1–10 HP range. At $119.43, this is the valve-only version — the right choice if you already have the strainer and shut-off hardware in place, or if you are replacing just the valve on an existing drain assembly. If you are starting from scratch with no drain hardware at all, look at the ADVSM kit at $154.00, which includes everything.
The problem this valve solves is straightforward: air compressors generate condensate every time they run. Hot compressed air enters the tank, cools, and water vapor drops out of suspension. In a working shop, a 60 to 80 gallon tank accumulates water steadily — every day, every run cycle. That water corrodes the tank steel from the inside out. It gets picked up by the air stream and carried downstream into your tools, spray guns, and air lines. It ruins paint work, accelerates rust in fittings and hoses, and degrades the performance of every air-powered tool in the shop. The ADVS handles draining automatically, every cycle, without anyone on the shop floor thinking about it.
How the Air-Operated Mechanism Works
The ADVS is a pneumatically actuated valve — it uses the compressor's own air pressure differential to open and close. When the compressor unloads at the end of a run cycle, the pressure drop across the valve actuates a drain purge. Condensate that has settled to the bottom of the tank gets expelled at exactly the right moment: after it has had time to settle, before the compressor reloads and stirs it back into the air stream.
There is no electrical connection. No solenoid coil to burn out. No 120V circuit to wire to the compressor. No timer to program or battery to replace. The valve does its job in response to the compressor's actual cycle — meaning it drains as often as the compressor runs, not on a fixed schedule that may miss busy periods or waste energy during slow ones.
Key Features
- Air-Operated Actuation: Powered by the compressor's own pressure differential — no electricity, no wiring, no timer
- Cycle-Based Draining: Opens at each compressor unload event, the optimal timing for condensate removal
- Valve-Only Configuration: Order this if you have existing strainer and shut-off hardware; order ADVSM if you need the complete kit
- 1–10 HP Rated: Sized for single-phase and small three-phase shop compressors in the most common HP range
- No Solenoids or Electronics: Purely pneumatic mechanism with no consumable electronic components
- Direct Tank Mount: Installs at the drain port on the bottom of the receiver tank where condensate collects
- Cast Air Build Quality: Minnesota-manufactured to the same standard as the Castair compressor line
Benefits for Your Shop
- Tank Longevity: Eliminating standing water stops internal corrosion — the primary cause of tank failure and failed pressure inspections
- Drier Air at Every Drop: Less moisture reaches downstream tools, airlines, and spray equipment
- Zero Daily Maintenance: No petcock to open, no schedule to keep, no one to forget
- No Electrical Work Required: Install anywhere on the tank without routing power to the compressor location
- Fast Payback: One averted tank failure or moisture-contaminated paint job pays for this valve many times over
What's in the Box
- 1x Cast Air ADVS air-operated drain valve
Note: This is the valve only. Installation hardware (strainer, shut-off valve, fittings) is not included. See the ADVSM at $154.00 for the complete installation kit.
Available Configurations
Cast Air offers multiple drain solutions for their compressor line. Here is where the ADVS fits in the lineup:
- ADVS — $119.43 (this valve): Air-operated drain valve, no install hardware. For replacements or installs where you already have the strainer and shut-off in place.
- ADVSM — $154.00: Same ADVS valve plus strainer, shut-off valve, and all mounting hardware. The complete first-install kit. Add $34.57 over the ADVS and get everything in one order.
- SDV03S — Electronic Drain w/Strainer, 115V: Timer-controlled solenoid drain valve. Requires 120V. Better for large or continuous-duty compressors where fixed-interval draining is preferred.
- SDV03M — Electronic Drain w/Install Kit, 115V: Electronic solenoid with complete install kit. Full-featured electrical drain for programmable interval control.
- PC14 — Petcock 1/4": Manual drain. Lowest cost. Requires someone to open it regularly. In practice, most shops should use something automatic.
When Does a Shop Need the ADVS vs. Other Drain Options
Choose the ADVS when:
- You are replacing an existing air-operated drain valve and your strainer and shut-off are already in place
- You want automatic draining without any electrical work at the compressor
- Your compressor is 1–10 HP and cycles on and off regularly throughout the day
- You prefer cycle-based draining over a fixed timer interval
Choose the ADVSM instead when:
- This is a first installation — the ADVSM includes strainer and shut-off hardware that you will need
- You want everything in one part number and one order; the $34.57 difference is worth not sourcing hardware separately
Step up to an electronic drain (SDV03S or SDV03M) when:
- Your compressor is larger than 10 HP or runs near-continuously — a pneumatic cycle-based drain may not keep up with the condensate volume
- You want programmable drain intervals independent of the compressor's unload cycle
- 120V is readily available at the compressor location and you prefer the electronic approach
The manual petcock (PC14) works when:
- Budget is the only factor and there is genuine shop discipline to drain every single day
- In most real shops, manual draining gets skipped — that is exactly the problem automatic drains solve
Technical Specifications
- Part Number: ADVS
- 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
- Configuration: Valve only — no install hardware included
- Kit Version: See ADVSM at $154.00 for valve + strainer + shut-off + hardware
- Price: $119.43
- Country of Origin: USA (Minnesota)
Why Buy From Air Compressor Factory Direct?
Air Compressor Factory Direct has specialized in Cast Air compressors and accessories since 2016. We stock the full Castair drain and filter accessory line so shops can get the right part from a supplier who understands the equipment. If you are not sure whether to order the ADVS or the ADVSM, call us — we will check what installation hardware you already have and give you a straight answer.
Every order ships free. Full manufacturer warranty on every Cast Air product. No restocking fees. If the part does not fit, we make it right. Our tech support line is staffed by people who know compressed air systems, not a general call center.
Call 866-217-0063 for quick answers and help!
