i watched a good video of a guy home hydro test his tanks with water / guage / quick connect and pressure washer . cool way for a home owner to know if its remotely safe to use . and yes these days insurance companys require so much stupid stuff it makes it hard to work .
i also have ready for install a auto tank drain kit so when the compressor is on it will auto drain each time . but my air is fairly dry in the heated shop and if i do long runs i make sure to drain the tank . i get maybe a few oz of water each time at most . and my big spin down seperator on the outlet gets even less during use . and i have no air dryer / cooler setup yet . my pump is 19cfm
@175psi . its a I.R. pump .
What autodrain have you got?
There are various different designs. Most of the ones I've used have been either mechanical float-operated or timed-solenoid valves. On properly big stuff, the mechanical float ones are pretty good IME, but for anything under about 10 HP and 200-gallons, or not running 24/365, the timed ones seem to do the job best.
The cheap ones are usually 1/2" ported and use a universal-Voltage asymmetric timer between a DIN-connector and the coil. The coil is not universal and needs to suit your supply Voltage. The big advantages these have over the float-type is that you can place them where you can easily access them and you can test them easily.
I usually replace the receiver drain valve with a ball valve, then pipe out of the ball valve in flexible nylon tubing to the Autodrain valve. Because it'll have 100+ PSI of air pressure behind any water, there's no need to have the autodrain valve at the lowest spot in the system: if you raise it to 4ft, where even a codger like me can see it and test it without squinting or bending, it'll only need 1.73 PSI to lift the water column, leaving 98+ PSI to move the water. I pipe out of the autodrain in flexible nylon tubing to wherever I'm going to collect, or dispose of, the condensate. This needs a little thought: it'll be spitting out the condensate followed by air. I usually try to arrange things so that the air is audible, but not excessive, when draining and doesn't result in mist or water in the shop.
Being audible helps reduce reliance on checking/testing: If I hear it working automatically, there's no need to test it that day. I use a push-fit connector to connect the nylon tubing out of the autodrain. This makes it easy to unplug the tubing and put a finger over the end of the fitting to check whether the valve is passing. This isn't a frequent thing, but it's nice to make it easy to check if the compressor seems to be running more than I'd expect. The biggest cause of passing autodrain valves IME is tiny balls of weld from the receiver welding on new compressors.
I usually set a 15 minute interval and the shortest drain time I feel comfortable with (typically it's about 2-3 seconds). I want it to activate while I'm in the vicinity and not doing anything particularly noisy, so I know it's working. I "expect" it to fail (the ball valve on the bottom of the receiver means I can isolate it to find out why/how and fix it). At work, we've used a lot of different ones over the last 35 years. The "better" branded ones might fail less often, but certainly not to the extent that it's reasonable to assume they won't fail. Cost tends to be at least 4 times that of the cheapies and a cheap one installed plus a spare on the shelf is the most cost-effective approach to all but a few industrial production situations.
If buying the cheapies, it's worth checking the threads used. The US uses 60-degree NP threads, where most of the rest of the world uses threads based on the old British Whitworth 55-degree threadform.
