Installation 7
0020300877_01 Energy
7
Installation and maintenance instructions
23
down differently by the manufacturer. The expansion ves-
sel volume depends on the total water system volume and
the initial system design pressure. For any system an ac-
curate calculation of vessel size is given in the current is-
sue of BS 5449 and BS 7074 Part 1. Example: For an initial
design pressure of 0.7 bar, the minimum total vessel volume
required is 0.063 x Total System Volume.
Note
A higher initial design pressure requires a larger
volume expansion vessel.
In GB, guidance on vessel sizing is also given in the cur-
rent issue of BS 5449 and BS 7074 Part 1. In IE refer to the
current edition of I.S. 813 “Domestic Gas Installations”. The
charge pressure must not be less than the static head of the
system, that is, the height of the highest point of the system
above the expansion vessel.
A manometer with a set pointer and covering at least 0 to 4
bar (0 to 60 lb/in
2
) shall be fitted permanently to the system
in a position where it can be seen when filling the system.
7.8
Connecting the heating flow and heating
return
2
1
1
Heating return connec-
tion
2
Heating flow connection
1.
Establish the heating connections in accordance with
the applicable standards.
2.
Check whether the connections (
Page 34) are leak-
tight.
7.9
Check compliance with the local gas group
The product's combustion has been factory tested and is
preset for operation with the gas group indicated on the data
plate.
The product is only authorised to be operated with natural
gas.
▶
Check the information about the gas type indicated on
the data plate and compare this with the gas type avail-
able at the installation site.
Condition
: The product design
is not compatible
with the local gas group
▶
Do not start up the product.
Condition
: The product design
is compatible
with the local gas group
▶
Proceed as described below.
7.10
Gas connection
1
1.
Establish the gas connection
(1)
in accordance with the
applicable standards.
2.
Purge the gas line before start-up.
3.
Check the entire gas line properly for leak-tightness.
7.11
Connecting the condensate discharge pipe
1
2
▶
Follow the instructions listed here and observe the legal
and local regulations on condensate discharge.
▶
Use PVC or any other material that is suitable for drain-
ing the non-neutralised condensate.
▶
If you cannot guarantee that the materials from which the
drain pipework is made are suitable, install a system for
neutralising the condensate.
▶
During installation remove all burrs from inside of cut pipe
work and avoid excessive adhesive which may trap small
pockets of water close to the pipe wall which can freeze
and build into a larger ice plug.
▶
For any installation the condensate must be free flowing
and not be possible for air back-pressure to prevent wa-
ter flow.
▶
As with other pipe work insulate the condensate dis-
charge pipe to minimise any risk of freezing and beware
when crossing cavities that the fall is maintained and the
pipe sleeved.
