Compressor problem

[pauls440]

Hi all can anyone help please my compressor relief valve keeps blowing, I've fitted a new switch but it still does it,
Now I say relief valve it's the little pipe that comes from the pump to the switch ,as it's a plastic pipe could this need changing,
Your thoughts and advice please

 

[carbon]

It does sound like the non return valve is not sealing correctly and draining the tank down. Drain all the air out and dismantle the non return valve hopefully its just a small foreign object holding it open

 

[pauls440]

Ok Chris thanks
Would you know if brake pipe is the same size so I could change the plastic pipe for metal

 

[rtbcomp]

I'd keep the plastic pipe, you'll have to mess around with the unions if you fit metal pipes.

You should be able to check the non-return valve without disturbing the thin pipe, as Carbon says drain the tank and then unscrew the back off the NRV.

http://www.mig-welding.co.uk/forum/media/img_2169_803-jpg.1686/full

http://www.mig-welding.co.uk/forum/media/img_2168_803-jpg.1685/full

 

[pauls440]

It seems to come from the new switch which is why I change it in the first place

 

[rtbcomp]

There is a small valve (the unloading valve) on the end of the thin pipe, this is where the air is coming from.

The valve opens when the pump stops to empty the pipe between the pump & tank (delivery pipe). If it releases air continuously when the pump is stopped then air must be coming past the NRV, and that wants checking first.

 

[pauls440]

Hi yes it happens straight away

 

[pauls440]

And ware is the nrv

 

[rtbcomp]

It's screwed into the tank and has the thick pipe from the pump and the thin pipe from the switch connected to it.

Post some photos of your compressor, just to make sure.

 

[pauls440]

My little pipe comes from the top of the pump and go's to the starter switch

 

[the snooper]

My little pipe comes from the top of the pump and go's to the starter switch

follow the main delivery pipe from the pump to the receiver and it will be at the end of that, it stops the air going back to the pump when it works

 

[rtbcomp]

My little pipe comes from the top of the pump and go's to the starter switch

That's feasible, photos would be a BIG help.