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9.4 Heating systems with plastic pipes
When connecting or using an underoor heating system, designed with plastic pipes, or plastic pipes are
used elsewhere in the installation, one should ensure that the plastic pipes used comply with the DIN
4726/4729 standard. It is set out in this standard that the pipes may not have oxygen permeability higher
than 0.1 g/m³.d at 40°C. If the system does not comply with this DIN standard, the underoor heating
component will have to be separated from the central heating appliance by means of a plate exchanger.
No recourse can be made to the terms of the warranty in the event of failure to observe the
regulations pertaining to plastic underoor heating pipes.
9.5 Gas connection in general
The local gas supplier should be consulted, at the installation planning stage, in order to establish the
availability of an adequate supply of gas. An existing service pipe must NOT be used without prior
consultation with the local gas supplier.
ATAG supplies boilers suitable for natural gas only and boilers for LPG only. Verify the identication
plate on the boiler if the boiler is suitable for the gas kind on site. The boilers cannot be converted to
another kind of gas.
Make sure that the gas pipe work does not contain dirt, particularly with new pipes.
The complete installation MUST be tested for gas tightness and purged as described in the above
code.
The boiler connection is provided with an isolation valve with 22mm compression tting, into which the gas
line can be tted.
9.5.1 Natural gas connection (NG)
The gas supply must comply to the current Gas Safety, Installation & Use Regulations, in accordance with
BS.6891.
The nominal inlet working gas pressure measured at the appliance should be 21 mbar +/- 2 mbar for Nat
gas (G20). Allowing for the acceptable pressure loss of 1 mbar across the installation pipework, it can
be assumed that a minimum permitted operating pressure of 18 mbar will be delivered to the inlet of the
appliance. (Reference BS 6400-1 Clause 6.2 Pressure Absorption). When tested at the gas valve, the
pressure drop from the meter to the gas valve must not be more than 3.8 mbar.
9.5.2 Propane gas connection (LPG)
The LPG installation has to comply with British Standard 813 and Domestic Gas Installations
Installing of a LPG installation should only be done by a registered LPG installer.
The tank must be provided with a high pressure regulator with a minimum capacity of 24 kg/h to reduce
the tank pressure from 5 to 1,5 bar. The 1,5 bar high pressure gas line should have a minimum diameter of
15mm. In the high pressure gas line a house pressure regulator must be installed. When tested at the gas
valve, the pressure drop from the pressure regulator to the gas valve must not be more than 3.7 mbar.