Multipoint 75/100 Accessories, Accessory selection

06Accessory selection

Multipoint 75/100 ACCESSORIES

Thermostatic blending valves

Pack U3 and U7 for use with all Multipoints;

Thermostatic blending valves allow water to be stored at high temperatures and blended with cold water to a preset outlet temperature. This provides over-temperature protection, and is ideal for the control of Legionellae and the extension of

system capacities.

PACK U3 TMV2

Connection 15mm compression.

Allows water to be safely stored above 60°C

Precisely controls outlet water temperature (range 35°C to 60°C)

Lockable control knob

Fail-safe shutdown

Incorporates check valves to prevent cross contamination

Operating pressure 0.2 bar to 6.0 bar

PACK U7 TMV3

Connection 15mm compression.

Fully approved under the TMV3 scheme to the DO8 specification

Allows water to be safely stored above 60°C

Precisely controls outlet water temperature (range 38°C to 46°C)

Unique adjuster key to prevent unauthorised temperature adjustment

Fail-safe shutdown

Incorporates check valves to prevent cross contamination

Operating pressure 0.2 bar to 5.0 bar

TMV Installation

Heater

Outlet taps	Hot outlet	Cold water in

Blended water	Pack U3 or U7
to outlets	blending valve

Balanced cold water supply

Technical Support

Heatrae Sadia offers a dedicated Specifier Advice line to provide information and advice on specification and installation. This is supported by a fully-trained national sales team, all of whom are qualified to provide further guidance and support locally.

Water expands by up to 4% when heated (See Fig. 1). This means that the design of the water heater and the installation in which it is used are critical. Conventional (vented) and unvented systems allow for expansion in different ways.

FIG. 1
	4.34
	4
%	3
%
S I O N	2
X P A N	1.2
E	1.2
E	1
	1
	0
	10	20	30	40	50	60	70	80	90	100
	T E M P E R A T U R E R I S E							O C

With unvented systems, there are no cistern tanks or open outlets to accommodate expansion. All systems above 15 litre, and some systems of 15 litre or less, employ an expansion vessel or an internal air-gap to accommodate expansion.

With larger systems (above 15 litre), expansion is accommodated either by a separate expansion vessel or an internal air-gap. Multipoint 75 and 100 litre units use an expansion vessel which is supplied factory fitted within the casing. They are supplied complete with all the necessary components and controls to provide a safe and efficient method of providing stored mains pressure hot water.

Building Regulations

Direct connection to the cold mains supply has been permitted in the UK since 1987. All units above 15 litre must be installed to meet the requirements of the Building Regulations. It is a legal requirement that the local Building Control Officer be notified of any proposed installation of unvented water heating systems over 15 litre capacity. Products up to 500 litre and 45kW must be approved by a recognised body such as the British Board of Agrément (BBA) and BEAB and be fitted by an installer who has successfully completed a recognised course in the installation of unvented heating systems such as CITB.

Requirements call for an expansion space (internal or external), safety devices to prevent the stored water exceeding 99°C, and pipework to convey discharged hot water safely away from the safety devices.