Ridgid - the regulated gauge immediately goes to zero
Bill, I have a Ridgid 3hp 5 gallon 2 tank compressor that pumps up to desired pressure in the tanks and shows same at regulator pressure gauge but when I hook up air hose the regulated gauge immediately goes to zero. It will then slowly rebuild back up but as soon as I apply use it will blast out sudden burst of air (air nozzle) and drop to zero again and then slowly build back up. Its as if the air from the tanks is partially restricted from filling the discharge manifold. At a total loss, Thanks for your help. Steve C.
Steve, the symptoms sound like a malfunctioning, or too small, air regulator to me, or a malfunctioning discharge coupler.
If you are comfortable doing so, with the tank empty and the compressor off, remove the discharge coupler, remove the regulator, install the discharge coupler where the regulator was, and use some air. If you get free flow of air to the tool, then it is clearly the regulator at fault. If the air is still blocked, then it is likely that your discharge coupler isn't opening fully(wrong connector) or the coupler is damaged.
If it is, I suggest you move to a full-size regulator of the same pipe size as your discharge pipe is. You will still be able to modulate the downstream pressure just fine, and a full size regulator has a much larger flow path, allowing higher flow of air through it.
See: www.about-air-compressors.com/regulator-questions.html for some air regulator resources.