Relief Valve

[EricH]

Originally Posted by Gregor

Just for curiosity's sake, why does the pressure relief valve have to be attached to the compressor with fittings (i.e. no tube in between), other than "because the rules say so."

What happens if the PRV is connected with tubing and there's a jam between the compressor and the PRV? Not too hard to do with tubing, mind you, particularly if you don't practice FOD control, or are a bit careless with the handling. Let's just say someone is heatshrinking some wire near the compressor, is a little careless, and manages to melt tubing closed.



Right. Pressure buildup, possibly to well over 125 psi. After all, the pressure switch will probably be down beyond the PRV as well, so it won't register that increase and shut off the compressor. Insert potential catastrophic failure of the pneumatics system here.

With fittings, you get a connection that is very difficult to jam, as well as being resistant to heat, pulling out, etc., and quite probably more resistant to bursting if someone still manages to get a nice jam going.

[FrankJ]

The rules say so is the best answer. Next reason is it is a good best practice. Much for the reasons that Eric described.