Bryant R-22 Servicing Systems on Roofs With Synthetic Materials, Brazing, Oil Charging

Table 4—Oil Charging

REFRIGERANT		COMPRESSOR MODEL			RECHARGE (FL OZ)		OIL TYPE
					COPELAND
PURON		ZP16---	26		38		3MA POE (32 cSt)
PURON		ZP32---	41		42		3MA POE (32 cSt)
PURON		P54			53		3MA POE (32 cSt)
PURON---	2 STAGE	ZPS20, ZPS30, ZPS40			34		3MAF---	POE
PURON---	2 STAGE	ZPS49, ZPS51			52		3MAF---	POE
					BRISTOL
PURON---	2 STAGE	T81J195			27		MOBIL 32BC
PURON---	2 STAGE	T81J285, 384			37		MOBIL 32BC
PURON---	2 STAGE	T81J515			62		MOBIL 32BC
				SCROLL TECHNOLOGIES
PURON		XG*32---	38		36		HATCO POE 32---			ST
PURON		XN*41---	56		53		HATCO POE 32---			ST
					COPELAND
R22		ZR16---	32		19	3GS---	32YMO (blended white oil)
R22		ZR38---			34	3GS---	32YMO (blended white oil)
				SCROLL TECHNOLOGIES
R22		XC*38---	42		36		Zerol 150---		T
R22		XC*43---	47		45		Zerol 150---		T
R22		XR*48---	60		53		Zerol 150---		T

Servicing Systems on Roofs With Synthetic Materials

POE (polyol ester) compressor lubricants are known to cause long term damage to some synthetic roofing materials. Exposure, even if immediately cleaned up, may cause embrittlement (leading to cracking) to occur in one year or more. When performing any service which may risk exposure of compressor oil to the roof, take appropriate precautions to protect roofing. Procedures which risk oil leakage include but are not limited to compressor replacement, repairing refrigerants leaks, replacing refrigerant components such as filter drier, pressure switch, metering device, coil, accumulator, or reversing valve.

Synthetic Roof Precautionary Procedure

1.Cover extended roof working area with an impermeable polyethylene (plastic) drop cloth or tarp. Cover an approximate 10 x 10 ft area.

2.Cover area in front of the unit service panel with a terry cloth shop towel to absorb lubricant spills and prevent run-offs, and protect drop cloth from tears caused by tools or components.

3.Place terry cloth shop towel inside unit immediately under component(s) to be serviced and prevent lubricant run-offs through the louvered openings in the base pan.

4.Perform required service.

5.Remove and dispose of any oil contaminated material per local codes.

Brazing

This section on brazing is not intended to teach a technician how to braze. There are books and classes which teach and refine brazing techniques. The basic points below are listed only as a reminder.

Definition: The joining and sealing of metals using a nonferrous metal having a melting point over 800_F/426.6_C.

Flux: A cleaning solution applied to tubing or wire before it is brazed. Flux improves the strength of the brazed connection.

When brazing is required in the refrigeration system, certain basics should be remembered. The following are a few of the basic rules.

1.Clean joints make the best joints. To clean:

⎯Remove all oxidation from surfaces to a shiny finish before brazing.

⎯Remove all flux residue with brush and water while material is still hot.

2.Silver brazing alloy is used on copper-to-brass, copper-to-steel, or copper-to-copper. Flux is required when using silver brazing alloy. Do not use low temperature solder.

3.Fluxes should be used carefully. Avoid excessive application and do not allow fluxes to enter into the system.

4.Brazing temperature of copper is proper when it is heated to a minimum temperature of 800_F and it is a dull red color in appearance.

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