Circulation Pumps - Mitsubishi Electric Ecodan HUS210FTC4ST Installation Manual

Circulation Pumps

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All Mitsubishi Electric pre-plumbed cylinders with FTC4 control systems come with 2 'A rated' Grundfos UPS2
25 - 60 circulating pumps fitted. One pump is located on the heat pump flow and the other is located on the space
heating return. In hot water mode only the pump on the heat pump flow will energise, whereas in heating mode
both pumps will energise in order to overcome the additional resistance of the heat emitter circuit and associated
pipework. This will ensure the required flow rate is maintained for each mode whilst consuming the minimum
amount of energy possible. The minimum flow rate for each Ecodan system can be found in the design section of
®
this manual. If minimum flow rate cannot be achieved with the pumps on speed 3 then additional pumping capacity
may be required – please contact Mitsubishi Electric Pre Sales Technical Support (01707 278666) for further advice.
The second (space heating) circulation pump is controlled by the 2 port valve motor outputs for all 2-zone systems
as shown by the below wiring diagram.
FTC4 Installation Manual
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