Daikin DPS - Page 117

Table 67: Alternate Initialization Sequence
See page 86 for more information about what is a compressor “step”.
Step 1 Step 2 Step 3
Inverter Compressor & Comp 3
Inverter Compressor Speed=minimum
Comp 3=Off
Inverter Compressor Speed=Smaller of Step 12 or
Maximum
Comp 3=Off
A
Inverter Compressor Only Inverter Compressor Speed=minimum
If OAT≤59°F, Inverter Compressor Speed=
Smaller of Step 12 or Maximum
If OAT>59°F, Inverter Compressor Speed=minimum
A
Outdoor Fan Outdoor Fan=100% ← ←
4 Way Valve (HeatPump) ON ← ←
Outdoor Coil Expansion Valve (EVO)
(HeatPump)
B ← ←
SVR (HeatPump) Closed ← ←
SVB
Normally Open
Closed If Discharge superheat>18°F
← ←
Indoor Coil Expansion Valve (EVI) EVI=100% ← ←
Time Duration 5 seconds 5 seconds C
A. Inverter compressor speed is increased until the 4-way valve is seated (discharge minus suction pressure >57 psi) and
as long as the discharge pressure is below 221 psi. inverter compressor speed is also increased if the discharge pressure
remains below 171 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 discharge pressure rises above 221 psi.
B. The outdoor expansion valve is controlled to keep the suction superheat between 3.6°F and 5.4°F.
C. 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 (differential pressure above 57 psi and either the discharge superheat above 18°F or the
discharge pressure is above 384 psi).
heat puMp
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