Daikin Heat Pump vs Nest

[ravee]

I have a Daikin concealed multi-zone heating and cooling heatpump recently installed in my home. I have an issue with this system.

Issue: The temperature read by nest thermostat is different compared to what I see in the DKN app which comes through the WiFi adapter which in turn connects to Nest thermostat. DKN app reads a much lower temperature compared to actual temperature at home or reads much higher temperature. For example, the current room temperature is 69F as read by Nest. But DKN app shows 74F. Because of this difference, the heating doesn't kick-in at the right temperature.

Any help is appreciated on what could be going on.

My HVAC system:

1. Daikin external unit: 5MXS48TVJU 
2. Internal concealed units: FDMQ24, FDMQ12, FDMQ09
3. Interface: Daikin DKN Cloud Wi-Fi Wireless Interface Adapter - Model AZAI6WSCDKB (one adapter for each internal unit)
4. Thermostat: Nest Learning Thermostat (one thermostat for each internal unit)

@CoolingWizard: I saw that you posted on a few threads on Daikin. Any input is appreciated.

[CoolingWizard]

@ravee , the DAIKEN app uses a calculation based on each indoor unit that is running to determine an ambient room temperature. Each of the indoor wall units has return air and supply air thermistors.  The Nest uses multiple internal thermistors and provides the ambient temperature in the area of the Nest thermostat location. Most conventional thermostats are located in a hallway or very close to where the air is returning to the indoor unit. Having said this, it is not possible to use a Nest Thermostat to control the DAIKEN system.  Therefore, I must assume that their home has a separate conventional HVAC system that’s being controlled by the Nest thermostat. 

AC Cooling Wizard