Compressor pressure relief valve for Harbor Freight compressor

[tipsy]

I have a harbor freight twin tank air compressor. They don't sell it anymore and it's not listed in their replacement parts list either. It's 2HP and 5 gallons. Lately the PRV has been releasing at 120psi so I adjusted the control to stop before that at about 110psi. I believe the control was set to go to 120. But the PRV is also leaking so I want to replace it. I'm not sure what PRV to get. 150's keep popping up on google as most common but I'm not sure if that's what I should get. I don't see any stamping on the tank to verify capacity. The label on the unit does say Max. Recommended Air Pressure: 100 PSI. I wasn't sure if that was for the entire tank or just the outlet pressure at the hose.
Any advice?
Thanks!

 

[tipsy]

Oh, and there is no stamping on the PRV itself to indicate what it might be

 

[Walkers]

125 pound reluef is pretty common, just google 125psi relief valve.

 

[wheelalignguy]

You can always scour facebook marketplace and find someone selling a horror freight air compressor for parts. I've done this a couple times and have plant of spares for the ol craftsman.

 

[Boilerhouse]

There should be two ratings for a safety valve, pressure (psi) and capacity (cfm). Just be sure that whatever PRV you get is rated to pop at or below the rating for the tank, although that seems like a bit of a guess in this case, but also, importantly, discharging a bit above the capacity of the compressor.
A safety valve discharging 3 cfm would be useless with a compressor that produces 5 cfm.

 

[finn]

Do an Amazon search. There are dozens of relief valves listed at ratings from SV-100 to SV-250. They typically cost less than $8.00.

 

[metalmagpie]

Pressure relief valves screw into holes with NPT threads. Yours probably has 1/4" NPT threads. Buy one with 1/4" NPT threads. Done.

(yes, make sure the specs match)