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4. INSTALLATION
4.1. Ventilation
The appliance may only be installed in a room that complies with the requirements stated
in national and local ventilation regulations.
BS5440 Flueing and ventilation for gas appliances of rated input not exceeding 70
kW net (1st, 2nd and 3rd family gases) –Part 2: Specification for the installation and
maintenance of ventilation provision for gas appliances.
BS 6644 Specification for the installation and maintenance of gas-fired hot water boilers
of rated inputs between 70 kW (net) and1.8 MW (net) (2nd and 3rd family gases)
IGEM UP/10 Edition 4 with amendments installation of flued gas appliances in industrial
and commercial premises.
4.2. Unvented installation
Unvented installations require a number of mandatory safety devices to be installed onto
the system to prevent the build up of excessive pressure within the supply system or the
storage vessel.
A bespoke unvented kit is offered and will supply the mandatory safety devices required
to comply with Part G3 of the Building Regulations as well as the Water Regulations.
The components shown in the drawing below must be installed in this order on the cold
mains supply :
INFORMATION:
The DR-SG water heater does not come with an integrated drain valve.
A tee, reducing fitting and drain valve are provided within the unvented
kit and must be fitted closest to the cold water inlet connection.
13.01.2023
Page 23 / 104
DORCHESTER DR-SG -
Installation, Operation and Maintenance