The Controller; How It Works; Operating Mode Principle - Earth Save Products SOLIS 11 Installation And User Manual

4 THE CONTROLLER

4.1 How it works

Start-up / Shut-down Sequence
When there is a 'call' for heat from the Solis, the water circulation pump starts followed by the fan
(30 seconds later) then, after a further 10 seconds, the compressor. (see above for set-to-work
delay).
When the heat pump switches off, the compressor stops first, followed by the fan 5 seconds later
then the water circulation pump shuts down 30 seconds after the compressor.
When the compressor shuts down, it has a minimum interval of 3 minutes before it will start again.
During a defrost cycle, the compressor stop/start interval is based on the defrost parameters
During defrost, the water circulation pump runs continuously.
Compressor Operation
Once started, the minimum run time for the compressor is 15 mins.

4.2 Operating Mode Principle

1) Space Heating Mode
The temperature can be set to a value between 10°C and 55°C, the factory setting is 45°C. This
should be set to the design flow temperature calculated by your heating designer.
2) Domestic Hot Water Mode
The DHW temperature can be set to any value between 10°C and 50°C. If a storage temperature
of greater than 60°C is desired, Earth Save Products Limited can advise on how to control this
through the unit using an auxiliary electrical heater controlled by the Solis. The default factory
setting is 50°C. Please note that the Solis unit will need to be altered before dispatch to enable
DHW production and requires an external storage vessel. A full explanation can be found in the
Solis Domestic Hot Water Appendix available from Earth Save Products Ltd.
3) Defrost Cycle
Solis heat pumps are fitted with an intelligent defrost cycle controlled automatically by the
microprocessors. A number of parameters are taken into account before defrost begins and
ends. The parameters set by the factory should not be changed without consulting your design
Engineer or Earth Save Products Limited. The defrost time will vary depending upon the working
conditions of the Solis unit. The length of, and interval between, defrosts cycles will vary.
Dated 17/09/19 V1.2
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ESP-HC-DHW 11DC
ESP-HC-DHW 17DC