Technical information

Combi 70 & Combi 90 Oil Boilers
24
Make the water connections
4.4
Fig. 16 - Combi 70 pipe positions
4 - BOILER INSTALLATION
Note: Water connections may be from the left or
right hand side. If using low level side exit flue, the
flue must be on the opposite side to the top water
connections. See Fig. 19 or 20 for flue/water
connection arrangements.
1 Fit any elbows, bushes etc. to the heating return
connection (bottom) before placing the boiler in
position if access will be restricted. Do not forget
to plug the unused connection.
If the boiler is to be positioned against a side wall, the
water connections may be taken from one side only.
2 If required, for easier access, the case bracing
bracket may be removed. Remove the four screws
securing the bracing bracket and lift it out.
3 Fit the grommets supplied in the water fittings pack
into the holes in the case side (left or right as
required).
4 Combi 70: Fit the three push-fit elbow connectors
onto the open pipe ends in the top right corner of
the boiler. See Fig. 16. Connect the pipework (not
supplied with the boiler) to the elbows as shown in
Fig. 17.
5 Start with the hot water outlet pipe (15 mm), then
the safety valve discharge pipe (15 mm), then the
heating flow pipe (22 mm) and finally the mains
inlet water pipe (15 mm) Ensure that the pipes are
fully pushed home into the elbow connectors.
Fig. 18 shows various possible pipework
configurations - the actual pipework route chosen
depends on the type and direction of the flue
system used and other site/system constraints.
Do not connect any external pipework to the boiler
at this stage.
6 Combi 90: Connect the pre-formed pipework,
supplied with the boiler, to the push-fit elbow
connectors as shown in Fig. 19.
7 Start with the hot water outlet pipe (15 mm), then
the safety valve discharge pipe (15 mm), then the
heating flow (22 mm) and finally the mains inlet
water pipe (15 mm). Ensure that the pipes are fully
pushed home into the elbow connectors.
8 Carefully manoeuvre the boiler into position, but
do not make any external pipe connections at
this stage.
9 Balanced flue models - proceed with the flue
installation as described in either section 4.5 (Low
level balanced flue) or separate fitting instructions
(High level balanced flue).
10 Conventional flue models - proceed with the flue
connection as described in section 3.8.
11 The safety valve discharge pipe must be routed
clear of the boiler to outside, to discharge in such a
manner that it can be seen but cannot cause injury
or damage to persons or property.
12 Do not turn on the mains water supply at this stage.