Inspection And Maintenance; Checking The Temperature And Pressure Relief Valve And Expansion Relief Valve; Checking The Charge Pressure Of The Expansion Vessel; Draining The Cylinder - Vaillant uniSTOR Operating Instructions Manual

7 Inspection and maintenance

7 Inspection and maintenance
Regular inspections and maintenance of the cylinder by
a competent person approved at the time by the Health
and Safety Executive are a prerequisite for long-lasting
operational readiness, reliability and a long working life.
The operational reliability of the cylinder may be
impaired and material damage and personal injuries may
result if the inspection and maintenance work is not car-
ried out.
The essential maintenance work on the cylinder and the
corresponding maintenance intervals are specified in the
table below.
i
When replacing parts, use only original replace-
ment parts from Vaillant Ltd.
Replacement parts
An overview of the available genuine Vaillant replace-
ment parts can be obtained from your wholesaler
(replacement parts catalogue, printed or on CD-ROM).
Maintenance work on
Cylinder
Check all connections to ensure that there are no leaks.
Check the temperature and pressure relief valve.
Check the expansion relief valve.
Check the charge pressure of the hot water expansion vessel.
Check water flow rates are correct (check and clean filters as necessary)
Ensure set temperatures are correct
Check the charge pressure of the expansion vessel, re-pressurise as necessary
Fill in the service section of the Benchmark cylinder commissioning checklist.
Tab. 7.1 Maintenance checklist
7.1 Checking the temperature and pressure relief
valve and expansion relief valve
> Open each valve manually by turning the valve cap and
check whether water is able to flow to the drain via the
tundish without obstruction. Make sure that both valves
sit correctly in their idle position.
7.2 Checking the charge pressure of the
expansion vessel
> Shut off the water supply pipe and open the nearest hot
water draw-off point to discharge the pressure from the
secondary water system.
> Use a pressure gauge to check the expansion vessel
pressure at the measuring point. If the pressure is below
3.0 bar, increase it using a suitable air pump.
> Fill in the maintenance section of the commissioning
report.
32
7.3

Draining the cylinder

> Close the cold water supply pipe.
> Secure a hose to the drain valve.
> Place the free end of the hose in a suitable discharge
position. The opening should be around 1 m beneath the
cylinder.
> Open the highest hot water draw-off point to reduce the
pressure and vent the water pipes, thus draining them
completely.
> Open the cylinder drain valve and leave open until no
more water escapes and the cylinder is completely
empty.
> Once the water has drained out, close the hot water
draw-off point and the drain valve.
> Remove the hose from the drain valve.
Installation and maintenance instructions for uniSTOR 0020111105_00
Maintenance interval
Annually
Annually
Annually
Annually
Annually
Annually
Annually
Annually