2-57
johNSoN coNtroLS
ForM 102.20-N1 (1109)
2
DX Coil Circuiting And Staging
On stacked coils, a minimum of four coil circuits should
be used to achieve full-face control (Fig. 2-83). Each
coil distributor circuit requires its own Thermostatic
Expansion Valve (TXV). Each condensing unit circuit
requires its own liquid line solenoid valve (LLSV).
When the condensing unit has two compressors per
refrigerant circuit, either one or two coil circuits may
be used for each refrigerant circuit depending upon the
cooling capacity.
Fig. 2-81 – StACKEd COil dESign - StAndARd
LD09145a
H4
H2
H1
D1
D2
H3
D4
D3
4 Distributor
Circuits Face Split
50 - 50% Interlaced
If one coil circuit is used (Fig. 2-84), the LLSV and
TXV must be sized to handle the full capacity of the
refrigerant circuit. When two coil circuits are used per
refrigerant circuit (Fig. 2-85), each TXV should be
sized to handle half of the capacity of the refrigerant
circuit and the LLSV should be sized to handle the full
capacity of the refrigerant circuit.
Fig. 2-83 – StACKEd COil CiRCuiting
LD09147a
Two Circuits
NOT Recommended
Four Circuits
Recommended
2
4
1
3
1
2
Fig. 2-82 – StACKEd COil dESignS - SQ SPECiAl
LD09146
H1
H2
H3
H4
H5
H6
H7
H8
D2
D1
D3
D4
D5
D6
D7
D8
H1
D1
D1
H1
H2
D2
H1
D1
D2
H2
D1
H1
H2
D2
D3
D2
D1
H1
H2
H3
H4
D1
D2
D3
D4
H1
H2
H3
H4
H5
H6
D2
D1
D3
D4
D5
D6
1 Distributor
Circuit
SQ Required
Single
HDR
Body
Single
HDR
Body
Single
HDR
Body
Single
HDR
Body
Single
HDR
Body
2 Distributor
Circuits 50 - 50%
Interlaced
SQ Required
2 Distributor
Circuits Face Split
SQ Required
2 Distributor
Circuits Row Split
SQ Required
3 Distributor
Circuits Row Split
66-33 Split
SQ Required
4 Distributor
Circuits Row Split
Interlaced
SQ Required
6 Distributor
Circuits Face Split
Row Split & Interlaced
SQ Required
8 Distributor
Circuits Row Split
& Face Interlaced
SQ Required
Summary of Contents for YORK SOLUTION LD09624
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