Controls, Start-Up, Operation, Service and ... - Climayoreo

Size 050, 055, 060
Contactor OFM(s)
Controlling Output
c
i
g
o
L
d
e
l
l
o
r
t
n
o
C
d
e
l
l
o
r
n
o
C
d
r
a
o
B
e
r
a
w
t
f
o
S
t
i
u
c
r
i
C
4
3
Common CDF.1 MBB Rly 6 OFC1 OFM1 Comp A1, A2, B1 or B2 ON
Common CDF.2 MBB Rly 5 OFC2 OFM2,3 Circuit A or B SCT or OAT
Common CDF.3 RCB Rly 1 OFC3 OFM4 Circuit A or B SCT or OAT
Ckt
A,
Ckt
B or
Ckt
A and
B running
Ckt
A,
Ckt
B or
Ckt
A and
B running
M.M. = NO Outputs ON Contactors ON Fans ON M.M. = YES Outputs ON Contactors ON Fans ON
Stage
1 CDF.
1 OFC1
OFM1
Stage
1 CDF.
1 OFC1
OFM1
Stage
2 CDF.
2 OFC2
OFM2,
3
Stage
2 CDF.
1,
CDF.
3 OFC1,
3 OFM1,
4
Stage
3 CDF.
1,
CDF.
2 OFC1,
2 OFM1,
2,
3
Stage
3 CDF.
1,
CDF.
2 OFC1,
2 OFM1,
2,
3
CDF.1,CDF.2,
CDF.1,CDF.2,
Stage 4 CDF.3 OFC1,
2,
3 OFM1,
2,
3,
4
Stage
4 CDF.3 OFC1,2,3 OFM1,2,3,4
2
1
MM
A1 A2 B1 B2
CONTROL
BOX
Low Ambient Prestart 1 (OAT ≤ 50F)
= Stage
1
Low
Ambient
Prestart
1 ( OAT
≤ 50F) = Stage 1
Low
Ambient
Prestart
2 ( 50F
< OAT
< 70F)
= Stage
3
Low
Ambient
Prestart
2 ( 50F
< OAT
< 70F)
= Stage
3
High Ambient Prestart (OAT ≥ 70F) = Stage
4
High
Ambient
Prestart
( OAT
≥ 70F) = Stage 4
Allow
Fan
Staging
if
OAT
< 70F
Allow
Fan
Staging
if
OAT
< 70F
CIRCUIT A
COILS
Size 070, 075
55
Contactor OFM(s)
Controlling Output
4
3
MM
c
i
g
o
L
d
e
l
l
o
r
t
n
o
C
d
e
l
l
o
r
n
o
C
d
r
a
o
B
e
r
a
w
t
f
o
S
t
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c
r
i
C
A CDF.3 RCB Rly 1 OFC3 OFM3 Comp A1 or A2 ON
B CDF.1 MBB Rly 6 OFC1 OFM1 Comp B1 or B2 ON
A CDF.4 RCB Rly 2 OFC4 OFM4 Circuit A SCT or OAT
B CDF.2 MBB Rly 5 OFC2 OFM2 Circuit B SCT or OAT
A1 A2
2
1
MM
MM=YES or NO Ckt A Running (w or w/o Ckt B) MM=YES or NO Ckt B Running (w or w/o Ckt A)
Circuit A Outputs ON Contactors ON Fans ON Circuit B Outputs ON Contactors ON Fans ON
CIRCUIT B Stage 1** CDF.1,CDF.2 OFC1,2 OFM1,2 Stage 1** CDF.3,CDF.4 OFC3,4 OFM3,4
COILS Stage 2 CDF.3 OFC3 OFM3 Stage 2 CDF.1 OFC1 OFM1
Stage 3 CDF.3,CDF.4 OFC3,4 OFM3,4 Stage 3 CDF.1,CDF.2 OFC1,2 OFM1,2
B2
B1
CONTROL
Low Ambient Prestart 1 (OAT ≤ 50F) = Stage 2 Low Ambient Prestart 1 (OAT ≤ 50F) = Stage 2
Low Ambient Prestart 2 (50F < OAT < 70F) = Stage 3 Low Ambient Prestart 2 (50F < OAT < 70F) = Stage 3
High Ambient Prestart (OAT ≥ 70F) = Stage 3 High Ambient Prestart (OAT ≥ 70F) = Stage 3
Allow
Fan
Staging
if
OAT
< 70F
Allow
Fan
Staging
if
OAT
< 70F
** This minimum stage valid only when one circuit is running AND M.M. = NO
otherwise the minimum stage is stage 2
Fig. 7 — Condenser Fan Staging Sequence (cont)
a48-8505