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Wiring Centre
MODEL:
UFH8-RF
UH8-RF Wiring
Connections
Mains Supply
Power supply into the UH8-RF which should be fused at 5 amps
these connections are marked
L = live or phase 230v AC 50/60Hz
N = Neutral
E = Earth
Boiler
This is the main call for heat for the system, there are 3 connections;
C = common
NO = normally open
NC = normally closed
Electrically this is a two-way switch, whatever supply is placed on
the C connection, is fed to the NC connection when there is no call
for heat.
This is then switched to the NO connection when there is a call for
heat.
Most systems will use the common (C ) and normally open (NO)
connections.
Pump
Used for an underfloor heating manifold pump.
Connections are clearly marked
L = live or phase 230v ac 50/60Hz
N = Neutral
E = Earth
When a thermostat configured as an under-floor heating zone
sends a call for heat to the UH8-RF, the live output will supply 230v
to the manifold pump.
It is recommended that this is fed through a high limit switch
placed on the heating manifold, to protect against mechanical
failure of the manifolds temperature control.
Valve
Used for an underfloor heating manifold valve.
Connections are clearly marked
L = live or phase 230v ac 50/60Hz
N = Neutral
E = Earth
When a thermostat configured as an under-floor heating zone
sends a call for heat to the UH8-RF, the live output will supply 230v
to the manifold valve.
H/W
This output is used to control a hot water cylinder thermostat
C = common
NO = normally open
NC = normally closed
Electrically this is a two-way switch, whatever supply is placed on the
common connection, is fed to the NC connection when there is no
call for hot water. This is then switched to the NO connection when
there is a call for hot water.
Normally the NO connection would be wired to the hot water cylinder
thermostat, then from there to the hot water valve, the valve auxiliary
switch will then start the boiler/other heat source.
Most systems will use the common and normally open connections.
Zones 1…8
Zones outputs are clearly marked
L = live out to actuator or valve
N = neutral to actuator or valve
There are two connections live (L) and neutral (N), both terminals
marked L are the same and both terminals marked N are the same.
Each zone output is numbered, Zone 1 will respond to radio signals
from the thermostat paired to zone 1, Zone 2 output will respond to
thermostat numbered 2 etc.
Fuses
Each UH8-RF is protected by 3 fuses
Fuse 1.
800mA, 20mm anti-surge fuse, this fuse supplies and protects
the internal electronics.
Fuse 2.
5amp, 20mm anti-surge fuse, this fuse supplies power to all
230v outputs from the board it protects the zone, pump and valve
outputs.
Fuse 3.
2amp, 20mm anti-surge fuse, this fuse supplies power to the
pump and valve outputs, it protects the board from overloads caused
by jammed valves or seized pumps.
The UH8-RF should be fitted as close as possible to the equipment it is controlling, but never within a metal enclosure, if this cannot be avoided an
extension antenna (EA1) must be fitted and placed outside the metal enclosure.
