This is the Prefect Glossary to help you understand the abbreviations, initials and terms we use to describe our products and services.

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Hopefully, any terms or abbreviations that you are not familiar with will be explained below. If you have any questions or queries please don’t hesitate to contact us.



Air Conditioning / Alternating Current

Analogue Dimming

Angled Head

Auto Shut Off Valve

(Denotes second generation of product)

Bottom Black (Pipe stat)

Building Energy Management System

Category 5 Cable

Control Unit

Digital Dimming

Distribution Use of System

Ecostat Controller

Flush Mount


Landscape / Live

Light Emitting Diode

Leak Detection Sensor

Low Voltage

Master Interface Unit



Passive Infra-Red

Infra-red programming

Power Unit

Root Mean Squared


Secondary Interface Unit

Slave Relay

Thermal Drive Valve

Top Red ( Pipe Stat)

Thermal Radiator Valve

Transmission Network Use of System



Volt Free Contact


Water Shut Off


Absence detection
When one of our products with a PIR sensor (Passive Infrared) is set to Absense detection the PIR is programmed to sense when occupants have left the room. When they enter the room they switch on the heating which activates the programme. On leaving the room the detector switches the heater to setback automatically. The heating control can also be switched off manually. Greater energy savings are made when Absence detection is employed.

A product suitable for mounting on the end of battens, highbays and linear style fixtures.

Boost mode is part of the 3-stage student profile. If the occupant of a room wants to increase the temperature in their room they press the up button on our control and this activates Boost mode, the heater will be turned on for the length of time that has been set in the programming process.

Refers to any product that is mounted on the ceiling.

Refers to products that do not protrude excessively from the wall or ceiling surface on which they are mounted.

Frost mode is part of the 3-stage student profile. If the occupant of the room leaves their room for an extended period, (this can be set during the programming process, 12 hours is a common setting) the control unit will notice either via a the PIR or the lack of activation by the up/down buttons, that the room is not occupied and will turn the heater off or to a lower setting (this is set during the programming process). The controller will monitor the room and maintain sufficient heat input to avoid damage from damp or frost.

Infrared is used to send settings and parameters from our handsets to the products. PIR sensors also use Infrared to detect occupancy of a room.

LOT20 Lot 20 is EU Ecodesign legislation for electric heating.  Effective from January 2018, all installations must comply with this minimum efficiency standard. The focus is on removing poorly controlled heaters from the market and replacing them with controls for temperature, timer, presence and open window detection amongst others.

The important part to understand of this legislation, is that heaters fitted with basic controls will no longer be permissible, but that doesn’t mean the control unit has to be integrated.

The Prefect Irus central control system and ecostat 2 range of controls are supplied with a bespoke slave heater. This option provides control through an impressive range of features. The specifications required under EU law are far exceeded and these master controls, fitted separately from the panel.

Our unique, patented, Energy Lock is supplied with the controller and simply slips into a slot on the heater making it operable.

The unit of illumination equal to the direct illumination on a surface that is everywhere one meter from a uniform point source of one candle intensity or equal to one lumen per square meter

Mains Borne Signalling
Mains Borne Signalling is the use of existing wiring within a buildings’ electrical circuit to transmit signals to control electrical devices. We use the Earth and Neutral wires to transmit data from our room nodes, via a Secondary Interface Unit to a Central Controller. The data is interpreted to monitor humidity, decibel, light and CO2 levels. Via the wiring we control heating systems. Mains Borne Signalling provides reliable communications and requires little or no  interference with a buildings infrastructure (in the case of installing data cabling) particularly in retrofit projects.

A PIR triggered switch that is operated using a replaceable rechargeable power cell (with a life expectancy in excess of 3 years).

As no neutral is required, the device is ideal as a replacement for a conventional light switch.

We refer to the control units for our heating systems that are mounted in each room as room Nodes.

The thermostat has an optimum start feature. The optimum start feature ensures the room is at the required temperature at the set time event. The thermostat will learn how long it takes to raise the temperature of the room it is controlling. Using this information the thermostat will calculate how long before the time event the thermostat must start heating to achieve the boost temperature at the time event. This ensures the room is at the required temperature at the required time without having to set the time event early to ensure the room is to temperature, which may waste energy.

These products have a removable back plate that is fastened to the ceiling or wall before the unit is then mounted onto this plate.

Presence detection
When one of our products with a PIR is set to Presence detection the PIR is programmed to sense people in the room. Detectors will switch on heating automatically when a person enters the room and then return the programme to Setback automatically when no movement is detected.

We use the term profile to describe individual room’s settings with regard to maximum and minimum temperature, timing, Setback and Boost mode operations.

Run time(s)
The Run Time is the length of time an electrical product controlled by one of our timers will operate when activated.

Run-back describes the length of time a product will run for when activated, if programmed fro 30 minutes, when the button is pressed the ‘counter’ will begin at 30 and work back to 0.

Sentinels are devices that can be attached to hot water pipes or fire doors, and other objects. They will have a sensor which could read temperature or simply recognise a connection i.e. on/off or open/closed. The sentinel is able to transmit data, using Bluetooth, to our room nodes, which in turn communicate with our portal to display information to Managers of a site.

The set-points are the ideal temperatures that are programmed for each of the modes in the 3-stage student profile i.e. Setback 18°C – Boost 23°C – Frost 10°C.

Setback mode is part of the 3-stage student profile. It is the default temperature level that has been programmed into our control units. If Boost or Frost modes have been activated, Setback is the temperature level the room will return to on when these modes have run their time or the unit is re-activated.

Surface-mounted products will be attached to a wall or ceiling through their back plate with the product then attached to the back plate. This means Surface-mounted products stand proud of the surface to which they are attached.

Tamper-proof means that there is no user access to a unit’s controls to re-programme settings and in some cases if attempts are made to alter settings the heater/hob or other appliance will be rendered inoperable until the unit has been reset.

Three-stage student profile
Three-stage student profile or programme is the use of Frost, Setback and Boost modes to manage energy use with our products. Temperatures are maintained at pre-determined levels (Setback), unless more heat is required, in which case Boost is activated (for a pre-determined time, before reverting to Setback), or Frost mode is activated (by a long period of inactivity in a room).

Some of our products are triggered by ‘touching’ the front surface of the unit.

Products with a trigger delay will begin their designated activity at a pre-set time after the button or some other form of activator has been generated.

User high/low adjustment
The PRE5004EC2 and PRE5204EC2 products in the ecostat2 range provide the occupant of a room with the ability to select High (the pre-determined top temperature) or Low (the pre-determined Setback temperature level) for the temperature of their room.

User variable adjustment
The PRE5003EC2 and the PRE5203EC2 products in the ecostat2 range provide the occupant of a room with the ability to set incremental levels of temperature in their room.

Valve Service Cycle
With wet heating systems, the valves on the radiators can become ‘furred’ over time by impurities in the water. This causes them to jam and cease working. Our products with the Valve Service Cycle feature will open and close the valves during periods when the valve is not being used regularly i,e in Summer months. This prevents residues building up to levels that prevent operation.

Volt Free Contact
The output channel comprises a mains voltage relay capable of on/off switching. The unit provides an isolated voltage free contact output.

These are products that are ideally situated on a vertical wall.

Wet systems
Wet refers to heating systems that use heated water to transmit warmth through pipes and radiators as oppose to electric panels.

Window-open detection
Our products will either use physical switches situated on the window frame to detect if a window is open. Most recently our products detect open windows by being alerted to drastic drops in temperature over very short periods of time, the only explanation being that a door or window is open allowing colder air from outside the room to enter, in these instances power is reduced to avoid wasting energy.