Technical data

20
I. Gas E. Publications
IGE/UP/1 Soundness testing and purging of industrial and commercial gas
installations.
IGE/UP/1A Soundness testing and direct purging of small low pressure
industrial and commercial natural gas installations.
IGE/UP/2 Gas installation pipework, boosters and compressors in industrial
and commercial premises.
IGE/UP/10 Installation of gas appliances in industrial and commercial
premises, Part 1 flued appliances.
Health and Safety Executive:
Guidance note PM5 - Automatically controlled steam and hot water boilers.
CIBSE Publications
CIBSE Guide B Heating, ventilating, air conditioning and refrigeration.
CIBSE Guide H Building Control Systems
CIBSE Guide Energy Efficiency in Buildings
CIBSE Commissioning Code B: 2002
Dept. of the Environment, Scottish Development Dept. & Welsh Office.
1956 Clean Air Act Memorandum Third edition
Third Edition of the 1956 Clean Air Act Memorandum.
Department of the Environment, Scottish Development Department & Welsh Office.
Location
The location chosen for the boiler must permit the provision of a satisfactory
flue system and an adequate air supply. The location must also provide
adequate space for servicing and air circulation around each unit.
This includes any electrical trunking laid along the floor and to the appliance.
Any combustible material adjacent to the boiler and the flue system must be
so placed or shielded to ensure that its temperature does not exceed 65°C.
Further details regarding boiler location are given in BS 6644. & BS 5440 part 2.
Purewell VariHeat boilers should be positioned on a level non combustible
surface that is capable of supporting the boiler weight when filled with
water, plus any ancillary equipment. Adequate space should be allowed
for installation and servicing. Refer to dimensional drawings on pages
8 & 9 for more details.
Adequate Water Flow
The Purewell VariHeat boiler is designed as a quick response, low water
content unit to run continuously with minimal operating problems. Care
should be taken in the initial design and layout, having due regard for
adequate water flow through the boilers, and the influence of the control
system. Hamworthy strongly recommend that Purewell VariHeat boilers are
installed using the primary circuit design to ensure adequate water flow
regardless of secondary circuit operating conditions. Refer to technical data
tables for minimum water flow requirements.
The control system and valves, where fitted, should be regulated to avoid
lower flows occurring. Condensing models are designed to operate with
systems operating at 20°C differential temperatures and return temperatures
as low as 30°C. Increased flow rates may be used for lower temperature
differentials with due regard for the increased pressure loss through the boiler.
Non-condensing models are designed for more traditional systems operating
at 11°C differential temperatures and return temperature no lower than
50°C. Differential temperatures to a maximum of 15°C are acceptable.
The installation of the boiler MUST be in
accordance with the relevant requirements
of the Gas Safety Regulations, Building
Regulations, IEE Regulations and the bylaws
of the local water undertaking. It should
also be in accordance with any relevant
requirements of the local gas region
and local authority and the relevant
recommendations of the documents below.
The following British Standard Codes
of Practice and Regulations have relevant
recommendations regarding the installation
of Purewell VariHeat boilers.
British Standards
BS 5440.Part 1 Installation and maintenance
of flues for gas appliances of rated input not
exceeding 70kW net.
BS 5440.Part 2 Installation and maintenance
of ventilation for gas appliances of rated
input not exceeding 70kW net.
BS EN ISO 4126-1 Safety devices for
protection against excessive pressure.
Safety valves.
BS 6798 Installation of gas appliances rated
input not exceeding 70kW net.
BS 6644 Installation of Gas Fired Hot Water
Boilers, 70kW to 1.8MW net input.
BS 6700 Design, installation, testing and
maintenance of services supplying water
for domestic use.
BS EN 806-2 Specification for installations
inside buildings conveying water for human
consumption – Part 2: Design.
BS 6880 Part 1,2 & 3 Code of practice for
low temperature hot water heating systems
of output greater than 45kW
BS 7074 Part 1 Application, selection and
installation of expansion vessels and ancillary
equipment for sealed water systems.
Part 2 Code of practice for low and medium
temperature hot water systems.
BS 7671 Requirements for electrical
installations. IEE Wiring Regulations.
Sixteenth edition.
Application & System Data
Purewell VariHeat Boilers