Giacomini R478 Underfloor Heating Thermal Actuator – Normally Open 2 Wire 230 v
£31.97 inc VAT (£26.64 ex VAT)
The actuators of the R478 series are normally open (NA). They allow them hydraulic supply of the circuits when there is no voltage and they have a cable
with two conductor for the connection to room thermostats or adjustment regulators.
The R478M version has a stroke end micro-switch for driving circulators or zone valves.
The R478V version has varistor for installation on places where the network voltage undergoes sudden changes that could damage the electronic
The R478MV version has either varistor or stroke end micro-switch.
In radiant panel heating and cooling systems, the normally open electrical actuators are to be preferred as they are not supplied for most of the time
involving a sensible electric energy saving.
Description In order to allow an optimal control of the room temperature, combining the energy saving with a high comfort, the use of electrical actuators on distribution manifolds, on radiator valves with thermostatic option, or on fancoil valves is advisable.
The series of R478 electrical actuators is characterised by an absolute quiet operation, long lasting lifetime as it has no mechanism subjected to wear and a sufficiently slow closing to prevent from water hammer phenomenon.
The operation mechanism is made of wax bulbs controlled by low consumption electrical PTC (Positive Temperature Coefficient).
• Product in compliance with the Directives B.T. 73/23/CEE and 93/68/CEE and ENEC 03 Certificate
• Product category: “Electrical actuators for assembly on radiators or radiant panel systems”
• Condition in absence of voltage: – Normally Open “NO” (R478)
• Linear motion • Valve working stroke 2,4 mm • Dust protection class 2
• Electrical discharge voltage 4 kV • Electrical enclosure to IP40
• Protection against direct contracts by means of double insulation (Class II) • Supply cable type H05 VV-F, useful length 1,5 m
• Opening time at ambience temperature for R478/R478V/R478M/R478VM versions, 230 V – 24 V ≈ 6 minutes
• Working room temperature: -5÷50 °C • Storage room temperature: -20÷65 °C
• Casing material flame retardant PBT V0-UL94 • Vertical assembly above the valve, or horizontal
• Rapid connection for Giacomini standard • Valve position mechanical indicator
• Micro-switch NC with open valve (R478M – R478MV)
Normally dispatched in 3-4 days