Carrier 09RH specifications Control Pressurestats for Low Stage Application, Characteristics

Control Pressurestat for Booster Applica- tion — The standard dual pressure switch furnished with the 5F,H compressor cannot be used for booster application. Replace it with an appropriate low temperature dual pressurestat that can operate at values shown in Table 24. Any commercial pressure switch is acceptable; for example, an Allen-Bradley Bulletin 836, type L33 for R-12 or type 1 for R-22.

Table 24 — Control Pressurestats for

Low Stage Application

CHARACTERISTICS			R-12	R-22, R-502, OR
					R-507/404A
Switch Action — High		Open on pressure rise		Open on pressure rise
	— Low	Open on pressure fall		Open on pressure fall
Range	— High	20″	Vac to 65 psig	30″	Vac to 110 psig
	— Low	30″	Vac to 20 psig	30″	Vac to 25 psig
Differential	— High	8 to 30 psi adjust.		12 to 30 psi adjust.
	— Low	5 to 15 psi adjust.		9 to 30 psi adjust.
Max Pressure — High		200 psig		300 psig
	— Low	120 psig		300 psig

F	+50
TEMPERATURE		R-12									120
	+40
									F		110
							TEMPERATURE
	+30									100
										90
INTERMEDIATE					DISCHARGE
	+20							80
	+10			SATURATED
SATURATED	0
	-10
	-20
	-100	-90	-80	-70	-60	-50	-40	-30			-20	-10	0
			SATURATED SUCTION TEMPERATURE F
	+50
F	+40
TEMPERATURE
										110
	+30							F		100
		R-22				TEMPERATURE
										90
	+20	R-502 (SEE NOTE)							80
INTERMEDIATE	+10				DISCHARGE
			SATURATED
	0
SATURATED	-10
	-20
	-30
	-40
	-100	-90	-80	-70	-60	-50	-40	-30			-20	-10	0
			SATURATED SUCTION TEMPERATURE F

NOTE: For R-502, lower saturated intermediate temperature is approximately 5 F.

Fig. 21 — Optimum Intermediate Temperature for 2-Stage Compression

(Incorporating Equal Compression Ratios per Stage)

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