Tech Tips: Working with R-401A
March 1, 2010
A Technician Tip From the PHCC Educational Foundation HVACR 201 Textbook...
Here is a quick review of the most important points to remember when working with R-410A:
• R-410A is to be used with designated equipment only. Do not use in retrofits.
• R-410A operates at pressures 50–70% higher than those of R-22. Be certain that your manifold gauge set, servicing equipment, and replacement components are designed to operate with the increased pressures of this refrigerant.
• R-410A cylinders are rose-colored (PMS 507).
• Recovery cylinders must be rated at 400 psi or higher. Use the DOT 4BA400 or BW
• Systems using refrigerant blends with a glide should be charged with liquid refrigerant to avoid fractionation.
• Manifold gauge sets should be rated at 750 psi (high side) and 200 psi (low side), with a 500-psi low-side retard safety zone.
• Use hoses with a 750-psi service pressure rating.
• Leak detectors should be of the HFC type.
• A liquid-line filter-drier is required on all units (or follow manufacturer’s directions). Do not use liquid-line filter driers with working pressures rated at less than 600 psi.
• Braze joints with a nitrogen purge. Do not use soft or low-temperature solder.
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