After looking through PiHome website I decided that this is just what I need to improve my existing controls – Heatmizer. The price and all functions are unbeatable. I was looking around but could not find any other option.

My old System

Downstairs: 7 zone underfloor heating with heating manifold – heatmizer underfloor controller and wired thermostats ( 5 of them faulty).
Upstairs: One Zone radiator controlled by a zone valve.
Hot Water: One Zone controlled by a zone valve.

My PiHome installation

PiHome Installation for 9 Zone Smart Heating

PiHome Installation for 9 Zone Smart Heating

9 Wireless temperature sensors
3 Zone controller
Raspberry Pi 3 with PiHome installed on SSD
Wireless Smart Home Gateway
PiHome Installation for 9 Zone Smart Heating

PiHome Installation for 9 Zone Smart Heating

The installation was straight forward as I did use downstairs the old controller – just wired in 2 PiHome zone controllers – on the links of old thermostats.
For upstairs and hot water I did use 1 PiHome Zone Controller – wired in the switched live of each valve ( upstairs zone and hot water).
PiHome Installation for 9 Zone Smart Heating

PiHome Installation for 9 Zone Smart Heating

Thank you PiHome