Type II — High-PressureQuestion 137 of 240
A technician plans to retrofit an old R-22 system to an HFC blend that uses polyolester (POE) oil. Which statement about the retrofit is correct?
a.Mineral oil works with all HFC blends, so no oil change is needed
b.The R-22 must be recovered, and the mineral oil is typically replaced with the POE oil the new refrigerant requires
c.Retrofitting removes the need for any leak repair
d.The remaining R-22 can be vented since the system is being changed
Explanation
In a retrofit, the existing R-22 must be recovered, never vented, and because most HFC blends are not compatible with mineral oil, the oil is usually changed to polyolester (POE). Components like the filter-drier are commonly replaced and the metering device may need adjustment. Venting during a retrofit is prohibited under Section 608.
Law Reference: 40 CFR §82.154Practice all 240 questions free — no signup required.
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