Air Compressor trouble

[WestieCorp]

A while ago my compressor was working fine until the check valve went off. So I looked at adjusting the pressure up and down - that didnt do anything, so I pulled apart the pressure switch and it looked a bit corroded, so I cleaned it up and put it all back together - still the valve goes off. So the other day I went and got myself a nice brand spankers Condor MDR2 pressure switch, put it on and had trouble with air leaking out the unloader valve and pressure not building up in the tank. So I fixed that problem, pressure builds up nicely now (no leaks) but the check valve still goes off. Has anyone experienced this before or know a solution?
Do I need to 'dial in' the new pressure switch?

CHeers,

[China]

Sounds like the pressure valve may need adjustment itself, check what pressure it blows off at, and adjust accordingly

[WestieCorp]

how do I do that? and how do I know when it is enough?

[Woodlee]

how do I do that? and how do I know when it is enough?


If the pressure safety blow off valve is blowing off before the compressor cuts out then the pressure in your tank is higher than the pressure saftey blow off valve setting .
1.adjust the pressure switch to shut of the compressor at a slightly lower pressure.until it cuts off the compressor with out the blow off valve activating.
or
2. adjust the pressure saftey blow of valve to blow off at a slightly higher pressure.
You can use the pressure gauge on your tank to do this if you have one fitted .

I would suggest backing the new pressure switch back a tad ,if you haven't touched the blow off valve at all .
It's also possible that the blow off valve spring has weakened or has some crud under the seat ,or the seat may need lapping in.

You could take both the switch and the valve to a instrument tech and get him to set them up against a master gauge to cut out and blow off at the correct pressure ,it would cost a few bucks , its a safety issue and maybe worth the time and small expense .

Industrial air receivers are usually inspected at regular intervals ,but there is no requirement for home user ones to be inspected .The condition of some of the home user ones I've seen over the years would make your blood curdle.
A compressed air explosion can be a devastating and spectacular event.
I don't want to scare you , but its just that I've seen the results of such an event.

Kev.

[WestieCorp]

All fixed!!!! the new switch has 3 points which you can adjust the differential and the cut-in pressure. I just backed them all the way off and then slighty increased it back gradually to get to the pressure point i wanted. Works like a brand new compressor now!

[daMANiack]

Hi,

Do you recommend to release the air compressor tank pressure when not being used? (I've normally release pressure after using)

I use a 3hp 50L belt at home and might only need it a couple times per week.

Do air compressor have a one-way valve leading into the air tank so that the held pressure doesn't cause damage to the piston seals etc.?

Cheerz :) :D ;)


A compressed air explosion can be a devastating and spectacular event.
I don't want to scare you , but its just that I've seen the results of such an event.

Kev.

[robyn2839]

i had the same trouble with mine ,did all the adjusting,etc then replaced the pressure thingy,and still when it reaches pressure it turns off then all the air pisses out till it starts again,does that sound like yours?. there is a brass valve at the fromt of the compressor where the air goes into the tank via a copper pipe from the pistons, and a small tube that goes to the pressure switch,well on the side of that valve there is a big nut on the side ,inside the nut is a spring with a rubber plug on the end of it . when the compressor is pumping air to the tank the rubber is pushed out ,bit when it reaches pressure and stops the rubber stops the air fron escaping ,thats wher the problem starts the spring corrodes and does not cut off the air so it just keeps coming out till it gets to certain pressure then starts comp again and so on...............bob

[Quasimodo]

"Do you recommend to release the air compressor tank pressure when not being used?"


My admitedly older model compressor has a one way valve at the entrance to the tank - when it pumps up to the set pressure, the switch turns off the motor and an unloader valve releases the pressure from the pressure switch and compressor head. This I think is designed to make the subsequent restart easier.

So, depending on your design, the pressure is probably only on the tank. The problem of not releasing air daily is that moisture buildup is not drained frequently so rustout of the tank is possibly accelerated.