Vaillant ecoTEC plus 937 Instructions And Maintenance Instructions - page 24
Installation and maintenance instructions ecoTEC plus 0020031552_03
24
h
Note
The drain pipe connected to the condensate
drain of the combi boiler must have a constant
gradient (45 mm per metre) and should be
installed and terminate within the building to
prevent the possibility of freezing up.
The condensate drain pipe must terminate in a suitable
location, e.g.:
a)
preferably the discharge pipe should run and termi-
nate internally to the house soil and vent stack
(at least 450 mm above the invert of the stack). A
trap giving a water seal of at least 75 mm (3) (built
into the boiler) should be incorporated into the pipe
run, and there must be an air break (4) in the dis-
charge pipe upstream of the trap. The connection to
the stack should not be made in a way that could
cause cross flow into any other branch pipe, or from
that branch pipe into the condensate drainpipe. This
can be achieved by maintaining an offset between
branch pipes of at least 110 mm on a 100 mm diame-
ter stack and 250 mm on a 150 mm diameter stack.
b)
connecting into the internal discharge branch (e.g.
sink waste or washing machine) with an external ter-
mination, the condensate discharge pipe should have
a minimum diameter of 22 mm with no length restric-
tion and should incorporate a trap with a 75 mm (3)
(built into the boiler) seal. The connection should
preferably be made down stream of the sink waste
trap. If the connection is only possible upstream, then
an air break is needed between the two traps. This is
normally provided by the sink waste.
c)
terminating in a gully (5) below grid level (6) and
above the water level. The external pipe length
should be kept as short as possible to minimise the
risk of freezing and should not be more than 3 m.
d)
at a condensate absorption point (soakaway) (7). The
external pipe length should not be more than 3 m.
Further information can be obtained from "BS 6798
Specification for installation of gas–fired boilers of rated
input not exceeding 70 kW net“. The condensate siphon
must be filled with water as described in Section 5.6 be-
fore the combi boiler is commissioned.
min.
180
Fig. 4.12 Installation space condensate siphon
d
Danger!
Danger of poisoning!
In order to prevent exhaust gases from escap-
ing from the combi boiler via the siphon, the
siphon must be filled with water before the unit
is switched on.
The discharge pipes must therefore be installed
in such a way that they do not cause an ob-
struction and sufficient clearance exists to
allow access to the condensate siphon.
There must be a minimum clearance of 180mm below
the siphon for access.
4.16
Installing the pressure relief discharge
pipework
4
3
2
1
Fig. 4.13 Installing the discharge pipe
The pressure relief for the heating system is integrated
into the boiler.
• Remove the discharge pipe with union nut and rubber
seal from the box of accessories for the shift load
storage tank.
• Insert the rubber seal (1) into the union nut (2) and
screw the discharge (3) onto the pressure relief
valve (4).
• The discharge pipework should be as short as possible
with a continuous fall from the appliance.
• The discharge pipe should terminate in such a way
that nobody can be injured and no cable or other elec-
trical components can be damaged if water or steam is
discharged. Please note that the end of the discharge
pipe must be visible.
h
Note
We recommend that the discharge pipe for the
pressure relief valve is not shortened.
4 Sequence of operations during installation