Table of Contents
Advertisement
accordance with the cleanser/inhibitor manufacturers' instructions. The system must be dosed
to the concentrations specified by the inhibitor manufacturer. Inhibitor concentrations must be
monitored and maintained on an ongoing basis. Failure of components such as, but not limited
to, pumps, auto air vents, pressure relief valves and motorised valves due to corrosion within
the system will not be covered by warranty.
3.1.4 Air Vents
The plastic plug of the auto air vent factoryfitted to the appliance must be loosened when filling
the system in order to bleed the air from the appliance. In addition to any factory fitted air vents
it is recommended that another air vent is fitted at the highest point in the system. Where the
flow pipework drops down from the appliance the installer must ensure that an automatic air
vent is fitted to the top of the pipework to prevent air being trapped in the appliance.
3.1.5 Drain Cock
A factoryfitted drain cock is fitted to the return pipe of the appliance, however drain cocks
should also be fitted to the lowest points in the system to allow the system to be completely
drained.
3.1.6 Pipework
We strongly advise that all installation pipework is run in copper. However, if plastic pipe is used
the last 1000mm of pipework connected directly to the appliance must be of copper. All
connections to the appliance must be made with compression fittings.
3.1.7 Heating System Design
The heating system must be designed for a fully pumped appliance.
3.2 Sealed Systems
3.2.1 Expansion Vessel
Refer to BS7074: PART 1, BS EN 12828, BS EN 12831 and BS EN 14336 for details of
expansion vessel sizing. The values given in the Table 4 below are for total system volumes
which include the water content of the appliance which can be found in Table 1: Product Data
(See page 3). The WS18 appliance is supplied with an 18 litre expansion vessel charged to 1.0
bar. This can accommodate a maximum combined appliance and system volume of 160 litres. If
these maximum total system volumes are to be exceeded, additional expansion capacity will be
required. The WP18 appliance is not supplied with an expansion vessel and if connected to a
sealed system, an expansion vessel must be fitted and sized according to Table 4 below.
INITIAL
CHARGE
(bar)
2.1
0.5
2.7
1.0
2.9
1.5
TOTAL
SYSTEM
25
VOLUME
(Litres)
4.2
6.3
8.3
5.4
8.2
10.9
7.8
11.7
15.6
50
75
100
Table 4: Expansion Vessel Volumes.
VESSEL VOLUMES (Litres)
10.5
12.5
14.6
13.6
16.3
19.1
19.5
23.4
27.3
125
150
175
21
16.7
18.7
20.8
21.8
24.5
27.2
31.2
35.1
39.0
200
225
250
22.9
25.0
30.0
32.7
42.9
46.8
275
300
Advertisement
Table of Contents
