Bp Unit Motorized Valve Control By Target Discharge Pipe Temperature - Daikin FTX25JVEA9 Service Manual

Si18-201
3.36 BP Unit Motorized Valve Control by Target Discharge
Pipe Temperature
Purpose of the This function uses the discharge pipe temperature to provide indirect SH control. It also enables
Function the management of the discharge temperature and wet operation (control in wet zone).
Outline The target discharge pipe temperature is obtained based on the indoor heat exchanger
temperature and outdoor heat exchanger temperature, the motorized valves' flow rates are
regulated so as to adjust the actual discharge pipe temperature close to the calculated value.
Target discharge temp. = α × condensing temp. - β × evaporating temp. + γ
The correction value for the motorized valve is determined based on the table (fuzzy table) of
deviation of the target discharge temperature and actual discharge temperature and per-unit-
time fluctuation of discharge temperature, and used for the operation of the motorized valve.
Main Functions
Target discharge temperature is set so
as to attain target superheating degree.
This inclination is considered to remain
the same regardless of operating condition.
(M1051)
System control
165