Atag iSteel 120, Руководство по установке

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ENERGY CUT OUT AND CYLINDER THERMOSTAT (INDIRECT ONLY)
As a requirement of Building Regulations the iSteel units are fitted with a thermal cut-out in addition to the normal control
thermostat. This unit should be fitted to the dedicated boss on the cylinder and wired to the two port valve controlling
the primary flow (see wiring diagram).
DISCHARGE ARRANGEMENT
This guidance is available as a download of the G3 Approved Document from www.planningportal.gov.uk.
The discharge from both the temperature relief and expansion relief valves can be joined together via a 15mm end feed
tee.
It is important that any discharge water does not collect in this pipe-work and can run freely to the tundish.
The tundish should be mounted in a vertical and visible position located in the same space as the unvented hot water
storage system and be fitted as close as possible and within 600mm of the safety device e.g. the temperature relief valve.
The discharge pipe-work from the tundish must be routed in accordance with Part G3 of the Building Regulations.
The discharge pipe from the tundish should terminate in a safe place where there is no risk to persons in the vicinity of
the discharge, be of metal and:
•
Be at least one pipe size larger than the nominal outlet size of the safety device unless its total equivalent hydraulic
resistance exceeds that of a straight pipe 9m long i.e. discharge pipes between 9m and 18m equivalent resistance
length should be at least two sizes larger than the nominal outlet size of the safety device, between 18 and 27m
at least 3 sizes larger, and so on. Bends must be taken into account in calculating the flow resistance. An alternative
approach for sizing discharge pipes would be to follow BS6700 Specification for design installation, testing and
maintenance of services supplying water for domestic use within buildings and their curtilages.
•
Have a vertical section of pipe at least 300mm long, below the tundish before any elbows or bends in the pipework.
•
Be installed with a continuous fall.
•
It is preferable for the discharge to be visible at both the tundish and the final point of discharge but where this is
not possible or practically difficult there should be clear visibility at one or other of these locations.
Examples of acceptable discharge arrangements are:
1. Ideally below the fixed grating and above the water seal in a trapped gulley.
2. Downward discharges at a low level; i.e. up to 100mm above external surfaces such as car parks, hard standings,
grassed areas etc. are acceptable providing that where children play or otherwise come into contact with
discharges, a wire cage or similar guard is positioned to prevent contact whilst maintaining visibility.
3. Discharges at a high level; e.g. in to metal hopper and metal down pipe with the end of the discharge pipe clearly
visible (tundish visible or not) or onto a roof capable of withstanding high temperature discharges of water and
3m from any plastic guttering systems that would collect such discharges (tundish available).
4. Where a single pipe serves a number of discharges, such as in blocks of flats, the number served should be limited
to not more than 6 systems so that any installation can be traced reasonably easily. The single common discharge
pipe should be at least one pipe size larger than the largest individual discharge pipe to be connected. If unvented
hot water storage systems are installed where discharges from safety devices may not be apparent i.e. in dwellings
occupied by blind, infirm or disabled people, consideration should be given to the installation of an electronically
operated device to warn when discharge takes place.
Any queries with regard to discharge arrangement contact your local council planning office.
600 mm Max