Daikin MicroTech III DPS User Manual

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www.DaikinApplied.com 63 OM 1263 • MICROTECH UNIT CONTROLLER
Table 43: Alternate Initialization Sequence, 3–15 Tons
Device Step 1 Step 2 Step 3 Step 4
Inverter Compressor & Comp3
Inverter Compressor Speed =
Minimum Comp3 = O󰀨
Inverter Compressor Speed =
Smaller of Step 12 or Maximum
Comp3 = O󰀨
← A
Inverter Compressor Only
Inverter Compressor Speed =
Minimum
If OAT ≥50°F or RAT ≥73°F,
Inverter Compressor Speed =
Smaller of Step 12 or Maximum
If OAT <50°F or RAT <73°F,
Inverter Compressor Speed =
Minimum“
← A
Outdoor Fan
Outdoor Fan = 0% if OAT <
68°F
Outdoor Fan = 5% if OAT ≥
68°F
B ← ←
4 Way Valve (Heat Pump) OFF ← ← ←
Outdoor Coil
Expansion Valve (EVO)
(Heat Pump only)
EVO = 100% ← ← ←
SVR (Heat Pump only) Closed ← ← ←
SVB
Normally Open
Close if Discharge superheat
>9°F
← ← NA
Indoor Coil
Expansion Valve (EVI)
EVI = 0% C ← ←
Time Duration 5 Seconds 5 Seconds
E = 15 Ton size F= 15 Ton size
D ≠ 15 Ton size NA
A. Inverter compressor speed is increased until the 4-way valve is seated (discharge minus suction pressure >57 psi) and as
long as the suction pressure is above 43 psi. inverter compressor speed is also increased if the suction pressure remains
above 71 psi. Comp 3 turns on if the inverter compressor speed is at maximum and these conditions are not met. Comp 3
is turned back OFF after 20 seconds if the suction pressure drops below 43 psi.
B. Outdoor fan capacity is controlled to maintain the discharge pressure between 171 psi and 221 psi. Outdoor fan capacity
is set to 100% if discharge pressure is above 427 psi. Outdoor fan capacity runs at least at minimum capacity if inverter
board (n) temperature >167°F.
C. EVI is controlled to keep the suction superheat between 3.6°F and 14.4°F.
D. Alternate Initialization lasts a maximum 15 minutes. It is completed early anywhere between 10 seconds and 15 minutes if
once the 4-way valve is seated (di󰀨erential pressure above 57 psi and the discharge superheat above 9.0°F).
E. Step 3 ends when the compressor has reached 65% full speed, di󰀨erential pressure is >26 psi for 3 seconds, the stage
has been active for 3 minutes, or Comp3 is active
F. Step 4 (initializaiton) is complete when the stage has been active for 15 minutes, or 4 way valve has set and discharge
superheat is above 9°F

Daikin MicroTech III DPS Specifications

General

Brand	Daikin
Model	MicroTech III DPS
Category	Controller
Language	English