Important Information; Ftc1 & Ftc2 Differences; Useful Numbers - Mitsubishi Electric ecodan PUHZ-W50VHA2 User Manual

FTC1 and FTC2 Differences
The Flow Temperature Controller 2 (FTC2) has some fundamental differences to the previous Flow Temperature
Controller (FTC1).
It is important that these differences are fully understood in order to ensure correct installation. This manual covers all
the changes which affect both the installation and the functionality of the system in detail, however the major changes are
highlighted below.
The interconnecting cable between Ecodan and FTC2 no longer carries 240V potential so does not need an earth
or switching through an isolator, this is now a two core cable not three core plus earth as on FTC1.
S1 is no longer in use on FTC2 and only connections between S2 and S3 are necessary, FTC2 is not powered from
the outdoor unit as is the case for FTC1.
DIP switch SW8-3 on the outdoor unit must be switched to the ON position in order for the Ecodan to recognise
that power for the interface is provided by the FTC2.
Immersion heater control can be provided directly from the FTC2 so no additional third party timer is required if
this control method is selected. The preferences for immersion frequency can be adjusted via DIP switches SW2-4
and SW2-5 on the FTC2 main circuit board. To use FTC2 to control the immersion heater directly, an optional
relay control box is required. If it is chosen to indirectly control the immersion heater as with FTC1 using an
additional third party timer, then DIP switch SW1- 4 must be switched OFF and SW2-7 switched ON.
When setting the hot water temperatures on the PAR-W21MAA remote controller please be aware that this is no
longer flow temperature to the cylinder as is selected on FTC1. For FTC2, cylinder target temperature is selected
so it is important to ensure that no more than 55
TH5 cylinder sensor is now supplied with the package and should be immersed in a dry cylinder pocket mounted
one third to half way up the cylinder, it should not be surface mounted in order to ensure accurate readings.
TH5 sensor should not be installed on pipework or undesirable operation will be encountered, this will be
especially true when automatic changeover mode is in operation.
The Honeywell wiring centre is no longer used with FTC2, all components are now wired directly to the relay
board.
Please ensure that after commissioning the PAR-W21MAA remote controller it is locked, this is essential as it is
possible to turn the system on via the PAR-W21MAA when there is no demand for hot water or central heating
through the programmer, in this case the system can run without any pumps or valves energised which will result
in a high pressure fault.
Only use spring return type zone valves with FTC2 units, this unit is not directly compatible with motor closed
valves.

Useful Numbers

After Sales Technical Support: 0870 3000 300
Hatfield Head Office: 01707 276100 (Heating Department 01707 278666)
Manchester Office: 0161 866 6080
Birmingham Office: 0121 741 2800
Bristol Office: 01454 202050
Wakefield Office: 0870 330 0347
Orpington Office: 01689 881030
Livingston Office: 01506 444960
North London Office: 01707 282480
For pre sales technical support please call your local office
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IMPORTANT INFORMATION

o
C is selected for hot water mode.
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