Fabdec EXCELSIOR, Installation Manual

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5. Servicing & Maintenance
Servicing and maintenance should only be carried out by a competent unvented hot water installer or Fabdec Ltd
authorised personnel.
Before any work is carried out on the installation, it must be isolated from the electricity supply.
Both the primary and secondary systems will contain very hot water that will scald, therefore care should be taken when
opening any joints, seals or valves.
Only use spare parts authorised by Fabdec Ltd. The use of other parts will
invalidate the warranty.
Excelsior cylinders utilising internal expansion will require checking periodically to ensure the air gap is sufficient. If the air
gap requires replenishing, follow the steps listed in the Commissioning section.
This product should be serviced regularly to optimise its safety, efficiency and performance. The service engineer should
complete the relevant Service Record on the Benchmark Checklist after each service.
Replacing air gap if lost during service (internal air gap – no expansion vessel)
1.
Turn off the mains supply to the unvented hot water cylinder
2.
Open a hot water tap, preferably on the same floor or the floor below where the cylinder is located.
3. Operate the temperature and pressure relief valve until water stops flowing from tap.
4.
Close the hot water tap and temperature and pressure relief valve.
5.
Turn the mains supply back on and bring the cylinder up to working pressure.
Replacing air gap if lost during service (external air gap – expansion vessel fitted)
1. Turn off the mains supply to the unvented hot water cylinder
2. Open a hot water tap, preferably on the same floor or the floor below where the cylinder is located to relieve
pressure.
3. Check pressure within expansion vessel. Re-pressurise to 3.0 bar if required.
4.
Close the hot water tap.
5.
Turn the mains supply back on and bring the cylinder up to working pressure.