Pressure relief valve replacement

[daleyd]

On mine the part is listed as a safety valve, item 34 on the linked website https://aircompressorpartsonline.com/twostage-air-compressor-pump-parts-b6000-p-3750.html.

That looks a different design to the clarke ones, maybe that is the safety valve on yours? I just had a gander at mine (ABAC) and it doesn't have anything obvious fitted between the pump and tank other than the non ret valve, but the safety valve is on the side of the pressure switch like the Clarke one.

 

[chrisg3103]

As mentioned its an unloader valve, in your case it seats at 30psi. It is there so the motor is not starting on full load.
When the tanks empty it will vent for a while until the system is up to at least 30psi, then seats.
Motor stops and the pressure between pump and non return valve drops, valve opens for next motor start.
Motor starts and the pressure between pump and non return valve will build near instantly seating the unloader valve so its bairly noticeable once the tanks above 30psi. Non return valve will act as a dead end until pressure is equalised to the receiver.

A pressure relief valve usually has a way of manually lifting it, such as a lever or pull ring and will have a direct line to the receiver, not blocked by the non return valve.

If you want to avoid having the unloader hissing at you everytime you fire up your compressor just close the outlet or regulator at the end of the day, dont go venting your reciever

 

[luke123]

Well i found my issue why it wasn’t working correctly, it had the 2 gaskets fitted but ive fitted a chunkier gasket the squish maybe differant as it does sound louder etc so maybe another gasket required on top ‍

 

[Al Strachan]

it'll only sound louder because its actually doing something
instead of just recirculating.

top work!