Domus Ventilation MAY102B Installation Instructions

TO PROFESSIONAL INSTALLERS:

Please leave this instruction booklet with the fan

on completion of the installation.

NOTICE

PLEASE READ

INSTALLATION INSTRUCTION

BEFORE INSTALLING

THIS PRODUCT

VENTILAT ION

Installation Instructions

This appliance is not intended for use by persons (including children) with reduced physical, sensory or mental
capabilities, or lack of experience and knowledge, unless they have been given supervision or instruction
concerning use of the appliance by a person responsible for their safety.

VENTILAT ION

Domus Ventilation

Cambria House
Caerphilly Business Park
Van Road
Caerphilly
CF83 3ED
Tel: [phone]
Fax: [phone]
Email: [e-mail]
www.domusventilation.co.uk

ISSUE 3

LAB304R

MAYFAIR CLASSIC

Fire Protected Wall/Ceiling Fan

MAYFAIR

Fire Protected Wall/Ceiling Fan

Product Function Guide

Single Speed May 102B

Single Speed fan unit. Requires external switching.

The Mayfair is a cartridge type centrifugal extractor fan for use where fire protection is required.
The Mayfair fan can also be installed as a basic extraction fan without the Fire protection
shutter.

It is fitted with a maintenance free rubber mounted motor. The cartridge system permits the
fan to be removed from the wall or ceiling without disturbing the ducting, wiring or wall fittings.
This facility greatly simplifies maintenance and cleaning procedures.

On new build and renovation projects the Mayfair system permits all the installation work to
be carried out in advance of the fan being fitted, therefore reducing the possibility of theft or
damage.

APPLICATION

BATHROOMS, TOILETS, UTILITY ROOMS, LOBBIES AND HALLWAYS

The Mayfair complies with all current Building Regulations.

Mayfair Range

Single Speed May 102B

Single Speed May 202B
with time delay Single speed fan with integral adjustable timer.

First isolate power supply. Remove the front cover by unscrewing

the central screw. Remove the four fan retaining screws positioned
at each corner and ease the fan away from its mounting. The timer
is next to the power pins. Turn the adjuster (at the end of the timer)
anti-clockwise for less overrun and clockwise for more overrun. The
timer factory set at minimum. The adjustment range is approx 30
seconds to 25 minutes.

Twin Speed May 402B
This model runs at slow speed when the room is unoccupied and

at high speed when the room is occupied. Usually operated by the
light switch.

Cleaning From time to time the fan will require cleaning. To do this, first

isolate the power supply and remove the fan from its mounting as
described under “adjusting timer”. Undo the three screws retaining
the impeller cover. Dust the blades and fan body with a dry brush.
The front cover and fire shutter may be washed in warm water.
Make sure that the fire shutter is dry and the fusible link is in position
when reinstalling.

Single Speed with Timer

Twin Speed

Fire Shutter (Wall Fix)

IMPORTANT: A BUILDING-IN FRAME IS REQUIRED TO FIX THE MAYFAIR FAN

UNIT.

Extract Volume

High Speed 79m3h (21.9 l/s)

Low Speed 36m3h (10 l/s)

May 202B

May 402B

May FD

WARNING: Failure to comply with Installation Instructions and

Cautionary Notes may invalidate warranty.

Wiring Installation

WARNING: ISOLATE ELECTRICITY SUPPLY BEFORE COMMENCING WORK

A Guide to Ventilation

WIRING REQUIREMENTS FOR DOMESTIC ELECTRIC FANS

It is recommended that fans be connected into the lighting circuit, with double pole (3mm) isolation,
provided before the room light switch and suitably fused, in accordance with I.E.E. Regulations.

Wall and ceiling mounted fans for fixed wiring should be connected to the power supply via a cable
with solid conductors of 1 to 1.5mm2 only.

IF IN DOUBT CONSULT A QUALIFIED ELECTRICIAN

MAY 102B

OPERATING SWITCH ISOLATOR SWITCH

S/L

N

OPERATING SWITCH

S/L

N

P/L

NOTE THE OPERATING SWITCH MUST BE SINGLE POLE

S/L

N

MAY 202B AND MAY 402B

ISOLATOR SWITCH

N

P/L

FRAME TERMINALS

S/L = SWITCH LIVE

N = NEUTRAL

FRAME TERMINALS

S/L = SWITCH LIVE

N = NEUTRAL

P/L = PERMANENT LIVE

WHERE TO SITE YOUR FAN

Incorrect siting of an extractor fan
can severely impair its efficiency. It
is therefore important that the fan is
correctly sited using the following
principles.

• To ensure maximum air flow through
the whole room, mount in the wall or
ceiling furthest from the air inlet point
and at high level.

• Do not position a fan where
temperatures are likely to exceed
40ºC.

• When installing in a room with an
open fire or stove without a balanced
flue, ensure that there is sufficient
replacement air to prevent the fan
drawing air back down the flue.

• A 230 Volt fan installed in a bathroom
must not be within reach of a person
using the bath or shower.

• Always use an in-Duct or Low Voltage
Fan (SELV) to ventilate a shower
cubicle.

Building Regulation Requirements

Room Extract Rate

Bathroom/shower room 54m3h (15 l/s)
with or without toilet.

Toilet. 21.6m3h (6 l/s)

Non domestic sanitary 21.6m3h (6 l/s)
accommodation (and/or per w/c or 3 Air
washing facilities). Changes per
hour.

Rooms without opening windows require fans
to be fitted with 15 minute overrun timers.

ELECTRICAL SUPPLY 230V AC~50HZ

IPX4

MODEL

MAY 102B
MAY 202B
MAY 402B

SLOW SPEED

–
–

20W

HIGH SPEED

35W
35W
35W

CAUTION

Fans incorporating electronic control systems may be damaged if used in conjunction with
fluorescent lamps.

If in doubt we recommend you contact our customer services department on 03443 715523.

WARNING:

Positioning the Fan Unit must be so as to
avoid the back flow of gases from open
flue or other open fire appliances.

Also to prevent combustion gases
entering the Air Inlet, the Air Inlet must not
be positioned above or within 11/2 metres
of a combustion flue vent.

NOT FOR USE IN SHOWER CUBICLES OR ABOVE BATHS FITTED WITH A SHOWER.

MAX ROOM TEMPERATURES 40ºC

Installation using building-in frame

WALL MOUNTED

In the chosen position (as high on the wall as possible) cut a hole through the wall to take
the 75mm discharge duct. 100mm duct may be used if preferred. In this case you will
require a 75mm discharge duct. 100mm duct may be used if preferred. In this case you will
require a 75mm to 100mm adaptor. The ducting must slope slightly downwards towards
the outside to allow for condensation drainage. When this has been done, position the
building-in frame with the discharge spigot at the top right over the discharge duct position.
Mark around the frame and cut an aperture to take the frame and fan. It is important that
the front edge of the frame is flush with the surface of the wall.

The aperture must be at least 100mm deep. If installing in a cavity wall with loose thermal
insulation, a cavity liner will be required. When the aperture is ready, grout the building-in
frame into position. If a fire shutter is to be fitted to the fan, make certain that the grouting
used is fireproof. Fit the discharge duct into position from the outside and trim to length.
Grout into position and fit a discharge grille.

While fitting the building-in frame, provision must be made for the power supply cable.

To fit the fan into the building-in frame, first align the power pins and discharge spigot with
their sockets and push gently into position.

CEILING MOUNTED

Select a suitable position on ceiling for fan. Ensure that the chosen position is between and
square to the roof joists. Using the building-in frame as a template, mark and cut out the
square hole to fit the frame into. Cut and fit two noggins to fit between the joists. Position them
alongside the frame aperture so they will support the frame when it is in position. Fit the frame
into position ensuring the front edge is flush with the ceiling surface. Secure firmly by screwing
through the holes in the side of the frame into the joists or noggins.

Seal any gap between the ceiling board and frame with fire proof grouting.

The discharge from the fan may be ducted through a roof cowl or through the eaves either
way, provision for condensation drainage must be made. For vertical duct, a condensation trap
can be made from flexible ducting. Horizontal ducting should slope downwards towards the
eaves.

To ensure maximum efficiency from the fan, flexible ducting and bends must be kept to a
minimum. Please refer to page 6 for relevant wiring diagrams. To fit the fan into the building-in
frame, first align the power pins and discharge spigot with their sockets and push gently into
position.