The UH3 uses a 5A fuse and can be replaced by the newer UH8 model. Capacity: 8 Zones, up to 4 actuators per zone. Key Features & Technical Specs.
Heatmiser UH3 Wiring Centre 8 Zone - New In Sealed Box
Heatmiser - UH4 Wiring Centre
Heatmiser UH8 Wiring Centre
Heatmiser - UH8 Wiring Centre
Heatmiser UH6 Wiring Centre
Heatmiser UH4 Wiring Centre - 4 Zone