Elta Fans
QuietflowDCV

              

QuietflowDCV. The powerful, easy and affordable demand ventilation solution.

Save time, money and the environment with Elta Fans' DCV Range. Download the E-Brochure and you’ll be saving in no time at all.

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Material Strength

A robust, lightweight unit with a galvanised sheet steel casing which is lined with flame retardant Class O rated acoustic lining for much improved sound characteristics.

Reliability

Motors have sealed for life bearings.

Low noise

Single fans are acoustically lined as described above so breakout noise levels are significantly lowered.

Low profile

Casings have a low profile design which allows ease of fitting in roof spaces.

Motor protection

All QuietflowDCV units with AC motors have integral thermal overload protection which prevents the motor from overheating. All QuietflowDCV units with EC motors have internal electronic overload protection.

Mounting

Mounting brackets are supplied fixed to the sides of the casing for ease of installation.

Space saving

The impeller axis runs horizontally across the unit which minimises the overall height of the unit and enables it to be fitted into roof voids.

Full accessory range

Speed controllers, fast clamps, anti-vibration mounts, electric heater batteries, silencers, panel filters, flexible connectors and non return dampers.

Warranty

QuietflowDCV has a 12 month warranty.

Quality impellers

The high efficiency backward curved centrifugal impellers are directly driven by an external rotor motor, mounted on a mounting plate fitted inside the fan casing, designed to provide reliable, continuous air extraction with a smooth airflow.

Easy access

There is easy access to the fan via the lid which means easy access for cleaning and maintenance.

Ease of installation

All models are designed for direct connection to standard diameter flexible or rigid circular ducting with 50 mm long spigots for ease of connection. Each spigot has an integral E PDM (Ethylene Propylene), UV + Ozone stable and resistant rubber seal which has a U shaped profile.

Electrical

All units are suitable for 220-240V operation. All the AC motor specified units operate only on 50Hz whilst all EC motor specified units can operate on 50Hz or 60Hz

Tested to the very latest standards

QuietflowDCV units are tested to ISO 5801:1997 (airside performance) and to BS 848 Pt 2:1985 (sound performance) at Elta Fans own test facility, meaning accurate, up to date information on performance and noise data that can be relied upon.

Quality assurance

All units are designed and manufactured with procedures as defined in BS EN ISO 9001: 2000.

Applications

Toilets, bathrooms, hotels, schools, colleges and libraries. Master and Slave configuration available where the slave unit will not necessarily require a DCV control package.

Changes in legislation

Building Regulations Parts L and F (effective April 2006), recognises the need for the creation of healthier working environments in the workplace for new and refurbished commercial buildings of all types. (The EU is working towards an energy reduction in energy consumption of buildings of 20% by 2010.)

Download the Legislation overview document for more information and details.
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Introduction

The QuietflowDCV range of in-line single fans as manufactured by Elta Fans Ltd. 46 Third Avenue, Pensnett Trading Estate, Kingswinford, West Midlands, DY6 7US, UK.
Tel: +44 (0) 1384 275800

Motors

The single range of units may have either an EC or AC single rotor motor fitted as standard. The motor contains sealed for life bearings. Insulation classification of motors is as follows:
• Sizes up to and including 400mm diameter is Class B Rating.
• 500mm diameter size has Class F rating
All motors are suitable for use in ambient air conditions up to 50°C

Casing

The robust 1.2mm galvanised mild steel sheet casing, is treated internally with a Class O rated (BS 476 Parts 6 and 7) ignition resistant acoustic foam lining. The wrap around folded casing is specially manufactured using integral motor mounting plates to provide additional rigidity for the casings.
Each casing provides a suitably sized circular spigot to suit the duct size required. EPDM (ethylene propylene) rubber U shaped seals (being ozone and UV stable) are used to ensure a good seal back to the duct that is to be attached.
A removable lid is provided as a standard feature to facilitate ease of maintenance and cleaning.

Impeller

QuietflowDCV units are tested to ISO 5801:1997 (airside performance) and to BS 848 Pt 2:1985 (sound performance) at Elta Fans own test facility.

Quality Management

All units in the Elta range are designed and manufactured to procedures as defined in BS EN ISO 9001:2000.
They are also tested in accordance with BS848 Part 2 1985 (sound performance) and ISO 5801:1997 (airside performance).

Controls Elements

The zone controller is positioned within the control box mounted on the side of each casing. The operational status of any of the sensor/enabling devices may be viewed from the Room Controller (RC), which will have been mounted at viewing level within the space being ventilated.
The zone controller and room control interface are connected via the IJ12 port using a SELV (Safety Extra Low Voltage) cable with a standard length of 3 metres, (a 10 metre long cable is available as an optional extra). The number of sensors, enabling devices or management interfaces such as a Building Management System (BMS) may vary according to the project size or complexity of control required.

Looking for something?

Whether it's a Press Release, a Wiring Diagram or just a copy of the E-Brochure, you will find any and all supporting documentation for QuietflowDCV right here.
All QuietflowDCV downloadable documents and diagrams require Adobe Acrobat Reader, you can get it here.
Technical Information Centre

 Technical


 Electronic Brochure

 Animated Video

 Wiring


 Operating & Maintenance

  • QuietflowDCV O&Ms


 Dimensional Data

  • QuietflowDCV Dimensions


 Changes in Legislation

  • Changes to the way we work


 Press Information

  • Information for the Press


 Accessories

  • Further Information on Accessories


Room Controller

The room controller is a programmable unit complete with a back lit LCD display that is the interface between the sensor and the DCV hub on the fan unit. This unit is programmed to indicate whatever sensing details are required (dependant on the type of sensor used). It is suitable for use within a temperature range of -20°C and +70°C and has a protection classification to IP20. Power consumption of 30VA for DCV zone controller. The RC is interfaced with the DCV zone controller mounted on the fan unit itself which is pre-loaded with the design and operational information for that particular fan unit. A 3 metre long SELV cable is provided as standard. The DCV zone controller has a protection classification of IP20 and is enclosed in a control module on the fan. The interface is capable of operating at temperatures between -40°C and + 50°C and an RH ambient humidity of maximum 95% RH.
Simple ON/OFF Switch for the fan with a basic potentiometer in order to provide variable speed control (for the basic fan unit only).
Dimensions (mm): 94(H) x 94(W) x 28(D)
Controls & Sensors

Humidity Sensor

A wall mounted sensor for measuring relative humidity when used in conjunction with a humidistat. High level of reliability with set point settings that can be locked (0 to 90% RH). The sensor has an accuracy of + / - 2% RH (between 40 – 60% RH) and +/- 3% RH in all other ranges. The enclosure has a protection classification of IP30.
Dimensions (mm): 100(H) x 85(W) x 30(D)

Pressure Sensor

Is available for measuring gases (except ammonia). The measuring element is made from a ceramic material to provide good stability and accuracy in measurement. Suitable for use in ambient temperature of -15 to +80°C and has a protection classification of IP54 and suitable for wall mounting. There are two working range options, a standard option suitable for 0 – 300 Pa with an option for a working range product of 0 – 500Pa.
Dimensions (mm): 85(H) x 100(W) x 50(D)

Temperature Sensor

Suitable for wall mounting this sensor has a range of temperature sensing of 0 to 50°C. The level of accuracy provided is +/- 0.3°C. with a protection classification for the wall mounted enclosure of IP65.
Dimensions (mm): 100(H) x 85(W) x 30(D)

PIR Sensor

This sensor will detect when a person enters a space. This detector has a pulse-detecting function that minimises the risk of false alarm and has a settable output on / off delay and protection classification of IP40. Working area of 15 metre x 15 metres, 110° angle can be used and the sensor is suitable for wall or ceiling mounting.
Dimensions (mm): 112(H) x 66(W) x 43(D)

CO2 Sensor

This transmitter incorporates the latest auto calibration processing. Within the same casing we have the option to combine the measurement of CO2 and temperature. The transmitter has the ability to measure concentrations of CO2 from 0 to 2000 ppm or any set range in between to suit the legislative requirements. If it also used to measure temperature, a range of 0 to 50°C is available. The sensor has a protection classification of IP30.
Dimensions (mm): 100(H) x 85(W) x 30(D)

QuietflowDCV. The powerful, easy and affordable demand ventilation solution.

Save time, money and the environment with Elta Fans' DCV Range. Downlaod the E-Brochure and you’ll be saving in no time at all.

Accessories

Fast Clamps

For fast, simple and secure connection of spigotted fans to circular ducts or ancillaries. Constructed from galvanised steel with a foam lining.

Click here to download more information

Non-Return Dampers

Prevents the reverse flow of air whilst the fan is not operating, hence avoiding unpleasant draughts. Galvanised sheet steel case incorporate spring operated aluminium sheet blades.

Click here to download more information

Electric Heater Batteries

Safe and clean heating with a maximum exit temperature of 40°C at 70% RH. Fitted with a manual rest high temperature cutout for safety. Casing is manufactured from galvanised sheet steel whilst elements are nickel chromium wire.

Click here to download more information

Panel Filters

Easily accessed via a removable panel the filter is compliant with BS EN 779 rating G3 with 85% arrestance. The casing is constructed from galvanised sheet steel for longevity.

Click here to download more information

Flexible Connectors

Fits directly onto the spigot to provide a flexible connection between the fan and duct or ancilliaries. Constructed from galvanised sheet steel and PVC coated polyester.

Click here to download more information

Silencers

In an effort to further reduce noise levels Elta’s silencers are infilled with a glass tissue faced high density mineral wool.
The external casing is pre-galvanised sheet steel with perforated steel lining.

Click here to download more information

QuietflowDCV. The powerful, easy and affordable demand ventilation solution.

Save time, money and the environment with Elta Fans' DCV Range. Downlaod the E-Brochure and you’ll be saving in no time at all.

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Efficiency, Controls & System Design

  • The primary purpose of ventilation is to provide good indoor air quality. Inadequate ventilation leads to poor air quality causing occupant discomfort and health problems. The overall energy usage of a ventilation system is dependent on three distinct elements:

Fan Efficiency

  • The fan is responsible for supplying a specified volume flow rate against the system resistance at the best possible efficiency and the lowest possible sound levels. Fans are normally selected for the worst case scenario and for most of the time a lower air flow would suffice. Speed controllable fans are therefore favoured to match the fan duty against the actual demand.

    • Specific Fan Power
    This is a measure in W/l/s of the energy input determined by the pressure losses of the duct system, the pressure losses inside the ventilation unit and the fan efficiency. A low system pressure loss combined with an efficient fan will result in a low specific fan power.



    Impeller
    Traditionally Building Services fans have tended to rely on double inlet forward curved impellers which have an impeller efficiency in the order of 60%. Far higher impeller efficiencies of around 80% can be obtained with aerofoil section backward curved centrifugal impellers. The QuietflowDCV range uses backward curved blades with excellent efficiency coupled with aerodynamically optimised inlet cones.

    Motor
    Direct driven motors eliminate the drive train transmission losses. Typical small AC asynchronous motors up to 1kW can reach efficiencies from 60% up to a maximum of 75%. The highest possible motor efficiencies in this power range of 80% up to a maximum of 90% can be achieved with electronically commutated DC motors.
    EC motors are the most energy efficient option with consistently high efficiencies across the speed control range and would be first choice if whole life costing is the prime consideration.

    Speed Control
    Closed loop speed control for both the EC and AC motor options provides major energy savings as the fan power is proportional to the speed cubed.
    Thyristor and inverter speed control has a negative effect on sound levels at reduced speeds due to electromagnetic harmonics in the form of airborne and structure borne noise. The lowest sound levels under speed control are achieved using auto-transformer voltage reduction or EC motor technology. The AC fan is supplied with an industry first auto-transformer controller providing uniquely smooth, quiet and responsive speed control.
    The EC motor has integrated electronics built into the motor to convert the incoming AC supply to DC and also provide the electronic commutation and regulate the motor speed.

Control System

  • Building ventilation systems often operate at constant or pre-determined ventilation rates regardless of the occupancy level of the building. In the past, ventilation rates were based on maximum occupancy with consequent energy wastage.
    The energy wastage is not only due to the fan operation, but also includes the energy used to condition the air, whether in heating or cooling mode.
    Demand Control Ventilation
    Demand control ventilation is recognised as being a method of ensuring a building is ventilated cost effectively while maximising indoor air quality. Significant energy savings are made by effective DCV which ensures that the ventilation rate continuously matches the current occupancy rate. The three main elements of the Elta DCV system comprise of the sensors, zone controller and wall controller.

    Sensors
    The sensors continuously measure and monitor ambient conditions in the conditioned space and provide real time feed back to the zone controller which adjusts the fan speed modulating the ventilation rate to match the specific use and occupancy of the building.

    Zone Controller
    The pre-programmed Zone Controller is factory wired and fitted in an IP55 enclosure to the QuietflowDCV fan minimising on site wiring. The 24V DC Room Controller is supplied for mounting in the enclosed space and connected to the Zone Controller by means of a 3m standard lead supplied with the fan. (A 10m section of lead is available as an optional extra).

    Room Controller (RC)
    The Room Controller provides a clear overview of the settings and status, with simple intuitive operation and unobtrusive aesthetic design.
    Available features include the following:

  • Remote enable:
    • BMS
    • Time Clock
    • PIR
    • Thermostat
    • Humidistat

  • Sensor control:
    • CO2 sensor: 0 - 2000ppm (P-band)
    • Temp sensor: +5°C – +30°C (P-band)
    • Humidity sensor: 30 – 95% RH (P-band)
    • BMS: 0 – 10 VDC (proportional)
    • Manual speed control (proportional)
    • Pressure sensor: 0 – 300 Pa (PID control)

  • Additional features:
    • Slave fan operation – supply & extract
    • Twin fan operation – duty share standby
    • Status indication
    • Min/Max speed setting
    • Damper operation
    • Heater battery operation
    • Trickle & boost option
    • Run on timer operation

System Design

  • Good system design is critical to reduce the overall energy costs as a reduction in the system resistance will proportionally reduce the specific fan power.
    The specific fan power equation can be re-written as follows:

Quietflow DCV

  • In order to obtain an energy efficient and effective ventilation system it is clear that equal importance must be given to all three inter-related elements:

    Fan Efficiency + Control System + System Design = Energy Efficient Ventilation

    The Quietflow Demand Control Ventilation range fulfills the criteria of providing good indoor Air Quality combined with low overall energy useage.