Thermsaver unvented water heater, Руководство по установке

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TUNDISH
The tundish supplied must be fitted visible to the occupier. The
discharge pipe must be 22mm copper pipe. Regulations do not
permit more than 3 x 90-degree bends between the unit
and the outflow. Between the temperature & pressure relief valve
and the first 90-degree bend there must be a fall of at least
300mm. The fall of the pipework must be continuous and the pipe
should terminate in the gully or be bent backwards onto an
outside wall, in a place where discharge cannot be injurious to
persons.
If you need to site the unit In the middle of the house then
your discharge pipe to the tundish can be as far away as 9m, which
in most cases is enough to run the final discharge point. After 9m,
increase the pipe size to a greater diameter than 22mm and
accordingly for subsequent 9m lengths, see table 1 on page 10.
COMMISSIONING THE UNIT
Switch on electricity to the immersion heater(s) (Direct system) or
switch on the boiler (Indirect system). Refer to the boiler
manufacturers instructions on commissioning.
Bring the unit to its maximum temperature setting of approx. 60
degrees Celsius. You should, on operating the water taps, have a
good flow of hot and cold water assuming adequate water is
supplied to the unit.
Check the water does not discharge via the tundish pipework
during heating.
Recheck all fittings/joints for possible leaks.
On completion of the installation, before turning on the mains
water supply ensure that all residual materials are removed by
means of flushing the system with a "fernox" type cleaner or
equivalent.
EXTERNAL EXPANSION TANK
This smaller tank is connected to the cold-water inlet side of the
vessel. Mount the tank according to separate manufacturers
instructions provided with the External Expansion Tank.
See fig 1 page 5.
SCALE
In hard water areas lower water temperatures can result in less
scale being deposited.
If water softener is used it should be capable of flows of approx. 50
lt/min, this will maintain maximum performance of the unvented
unit.
If no descaler or softener is used then the heating element(s) will
need descaling periodically for maximum efficiency.
DRAINING
Switch off electrical power to immersion heaters and/or shut down
the boiler. Close the stopcock valve to isolate the unit.
Attach hosepipe to the drain cock having sufficient length to take
water to a suitable discharge point.
Open drain cock
Open hot water tap nearest to the unit.
If water fails to drain from unit, vent the system by
opening the temperature pressure relief valve.
DISCHARGE PIPEWORK
It is a requirement of Building Regulations that any discharge from
an unvented system is conveyed to where it is visible, but will not
cause danger to persons in or about the building. The tundish and
discharge pipes should be fitted in accordance with the
requirements and guidance notes of Building Regulations. Building
Regulation G3 Requirements and guidance section 3.9 reproduced
in the following sections.
Information Sheet No. 33 available from the British Board of
Agreement gives further advice on discharge pipe installation. For
discharge pipe arrangements not covered by G3 Guidance or BBA
Info Sheet No. 33 advice should be sought from either your local
Building Control Officer
SCHEMATIC DISCHARGE
PIPE ARRANGEMENT
Fig.6