Brass Electric Solenoid Valve, 3/4" 12V Air Valve Normally Colsed for Water Air Gas Fuel Oil

Great quality and exactly as described. It works perfectly for what I needed, and the overall value is excellent. I’m really happy with this purchase and definitely recommend it

Funciona muy bien , muy buena calidad la he conectado con un panel solar y baterias

This is verifiably a direct acting solenoid valve, meaning that all movement of the diaphragm is from the energized coil itself. It does NOT require a minimum operating pressure to fully open, which is a much more common design to find. However, that capability comes at a price: operation requires a very powerful coil. But powerful coils draw high CURRENTS and cannot sustain that full current for more than very short periods without OVERHEATING. If your application only requires that the valve be energized for 5 seconds every few minutes and NO MORE, you'll probably be fine using it as-is. Otherwise this MUST be driven using some form of active current/voltage control, i.e. PWM. The resistance of the coil for the 1/2" 12 VDC version measures 5.5 ohms, drawing just over two amps at 12 volts, dissipating 26 watts of heat, which is quite a lot in such a small space. The secret to success is understanding that full power is only needed for a brief time to initially open the valve but a MUCH smaller current will HOLD the valve open. In my case I've got an Arduino Mega driving an H-bridge motor controller that actually powers the coil. To open, full current is supplied for about 100 milliseconds after which it drops to a fraction of that by switching to PWM with around a 30% duty cycle to maintainin the open position. Using this scheme I've yet to have a failure to open or to stay open and the body of the valve never goes above ambient even after hours of being powered. The only other things to be aware of are that it makes a VERY loud click when activated and the threads are NOT NPT, they are not tapered - so expect to use a LOT of sealing tape if using conventional pipe fittings.

I bought the first one in late April 2023 for a machine that had a valve in need of replacement sometime in the future. For various reasons, I didn't get to install it until late Jan. 2024. Installed it, turned it on for about 10 seconds and it worked fine. Turned it off for about 20 seconds and then turned it back on, and it didn't work. Tested the continuity of the coil and had none - the coil was toast. I wrote it off to 'Ya know, it happens. Sometimes a bad part comes off the line.' (I've done industrial maintenance and service work for over 35 years in manufacturing, I get it) I ordered another valve and put it on the day it arrived (today), didn't work at all. Continuity check of the coil showed it was toast right out of the box. Both valves were ordered and shipped as 220V AC coil valves, and before putting each on, I tested the voltage on the coil wiring. This ain't my first time hooking up something as simple as a solenoid valve, as a matter of fact, it doesn't even fall into the first several thousand times I've done it. But it IS my first time getting two brand new components (even Chinese made crap) that were bad right out of the box. I just dropped a little over $120 bucks on a non-Chinese 1/2" solenoid valve (hard to find), and I'll be returning this paperweight that has cost me immeasurable amounts of time, money, and pissed offedness. I hold my nose whenever I buy Chinese crap, but I used to think it was because they were trying the best they could in spite of their skewed economic incentives in the system, now I'm becoming increasingly convinced that they are doing this on purpose.

Valve works fine, but wires come the same purple color. Not like the picture.

Well, it IS a solenoid. It ALSO gets rocket hot if powered up for more than a few seconds directly. If you want to risk it, you MUST use an H Bridge motor driver and an MCU to drive it full and then about 30% PWM once it's open or you will do damage to your project and your home. I gave it 3 stars since it does in fact work perfectly as a solenoid. It is easy to install though the threads don't seem to be NPT. Like all direct drive solenoids, it makes a big 'ole clunk when it is activated. I personally like that confirmation but if you are putting it into a project where quiet operation is desired, this is not for you.

Seems well made, holds air pressure well, and releases quick upon applying the 12V. My application is only for short quick releases of pressure, so no issue with the solenoid getting even warm.

good

Good

Work excellent

Didn't survive after one winter in Vancouver BC. At the end of the winter it got stuck in the open position (the 2 valves I purchased), I had to replace and throw them both to the garbage. I ordered a couple of different valves that hopefully will function in the next summer time will tell...

Marche tres bien

First time using this to operate auxiliary fuel tank drain and shorted out after about 20 minutes of use. Poor product