Mitsubishi Electric Ecodan HUS210FTC4ST Installation Manual page 49

Electrical Installation
24
Fossil Fuel Boiler Connection
As shown on the schematic for Ecodan
technologies into a common system.
This setup provides the option for the FTC4 to intelligently control and prioritise either heat source, dependant on
either an outdoor temperature, energy use, cost or CO
control thermistors (PAC-TH011HT-E) which must be purchased separately and are required for this type of
installation.
Only space heating operation can be supplemented by the boiler; hot water mode is not possible directly from the
FTC4. When installing a boiler and Ecodan
position of the low loss header means that both heat sources will be common to both DHW and space heating.
However, please note the boiler will only operate in space heating mode. Please refer to the schematic earlier in
this manual for clarification.
As boiler operation commences, pump overrun will occur meaning that all circulators will be energised. This
continues for a time dictated by the settings entered under 'economy setting for pump'. As detailed in the 'main
controller operation' section this should always be set to 3 minutes with this option turned on via the tick box.
It is assumed the boiler will have its own dedicated circulation pump which is interlocked with the boiler not the
FTC4. Once the pump overrun period has ended, the main circulation pump on the cylinder (OUT1) and the
dedicated Ecodan
circulator and the boiler circulator are providing flowrate on each side of the low loss header.
The boiler control output (OUT10) has no voltage across it, unlike the other 240V outputs. It MUST be decided
prior to installation if the boiler in question can be controlled by this method or if a control voltage (AC/DC) is
required when boiler operation is ON.
For more details, refer to the installation manual of PAC-TH011HT-E.
Installation & System set up
1. Set Dip-SW 1-1 to ON "With boiler" and SW2-6 to ON "With Mixing tank".
2. Install the thermistors THWB1 (Flow temp.) and THWB2 (return temp.) *1 on the boiler circuit.
3. Connect the output wire (OUT10: Boiler operation) to the signal input (room thermostat input)
on the boiler. *2
Remote controller settings
Go to Service menu > Heat source setting and choose "Boiler" or "Hybrid". *3
1.
2. Go to Service menu > Operation settings > Boiler settings to make detailed settings for "Hybrid" above .
*1 The boiler temp. thermistor is an accessory.
*2 OUT10 has no voltage across it.
*3 The "Hybrid" automatically switches heat sources between heat pump and boiler.
and fossil fuel boiler connection, it is possible to combine the two
®
in conjunction with a Mitsubishi Electric pre-plumbed cylinder, the
®
circulation pump (OUT1 with relay protection) will de-energise meaning that the space heating
®
(continued)
emissions. Full instructions are provided with the boiler
2
FTC4 Installation Manual
49