14
6.2.3 HCH Model
HCH boiler can be installed as heat only boiler or a systen boiler.
Figure 8: HCH Boiler
Figure 9: Installation Loop for HCH Boiler (System Type Installation)
**External WRAS appoved fillin loop must be added during installation.
1- Main Exchanger
2- Mixer
3- Fan
4- Silencer
5- Pressure Sensor
6- Condensate Trap
7- Gas Valve
8- CH Return Temperature Sensor
9- CH Supply Temperature Sensor
10- Ignition-Ionisation Electrode
11- Flue Gas Sensor
12 – Rain water collection reservoir
Water main
BS Stop Valve
Fixed spindle type
Wras Approved
Filling Loop**
DHW
DHW
Storage Tank
CH Supply
CH Return
Expansion Vessel
3 bar
Safety
Valve
