Overview Of The Controls - Mitsubishi Electric EHST20-Serie Installationshandbuch

2
introduction

Overview of the Controls

Built into the front of the indoor unit is the Flow Temperature Controller3 (FTC3).
This device controls the function of both the outdoor heat pump unit and the
indoor unit. The advanced technology means that by using an FTC3 controlled
heat pump you can not only make savings compared to traditional fossil fuel type
heating systems but also compared to many other heat pumps on the market.
As explained in the earlier section, 'How the Heat Pump Works,' heat pumps are
most efficient when providing low flow temperature water. The FTC3's sophisti-
cated technology enables the room temperature to be kept at the desired level
whilst utilising the lowest possible flow temperature from the heat pump.
The controller uses temperature sensors around the heating system to monitor
the air and flow temperatures. This data is regularly updated and compared to
previous data by the controller to predict changes in room temperature and adjust
the heat pump output accordingly. By monitoring not only the outdoor ambient,
but the room and water circuit temperatures, the heating is more consistent and
sudden spikes in required heating are reduced. This results in a lower overall
flow temperature being required.
5
Ambient
temp
sensor
Flow temp sensor
Return temp sensor
<How it works>
Temperature data is regularly received by the FTC3 from temperature sensors
around the heating system. The most recent data is used with the previous tem-
perature readings to predict the flow temperature required to keep the room tem-
perature constant.
The room temperature sensor can either be wired or the Mitsubishi wireless re-
mote controller can be used as it incorporates a temperature sensor. For more
information on room temperature sensor options see section 'Remote Controller
Options'. (Page 24)
Room temp sensor
FTC3
20°C