Mycom Relief Valve

[maddocks]

I am retrofitting an older propane based system to have a much higher suction pressure and flow (but same condensing temp). We've bought a new condenser and replaced the motor for the higher power requirements, but am wondering about compressor relief valve sizing. The compressor is a P8WB recip machine and the relief valve is a Mycom but I have no idea on orifice or capacity. Any suggestions? How do I resize this orifice - am I required to?

[charlie n]

If the relief valve was originally sized for propane according to the B-52 code (Canadian) there is no need to change it when you change the operating condition of the compressor. If the valve is over years old, it should be changed according to code requirements.

[maddocks]

charlie: This is great! Thanks. How many years is it before I require replacement? You were typing and missed the # of years.

[charlie n]

Sorry, 5 years

[IceMan_4000]

Charlie also note that you can size the capacity of the valve on the lowest capacity of the machine if there is a means of force unloading at high pressure situations. Since you are using a P8WB machine you can use something like the CP1 controller from Mycom to force the compressor to be a 2 cylinder when pressure approaches relief pressure.

This can make a very large difference on size of valve and the line from it.