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4.0 INSTALLATION - DISCHARGE PIPE REQUIREMENTS
4.1
The discharge outlet from the Pressure (Expansion) Relief Valve and the
Temperature/Pressure Relief Valve (if fitted) must be connected to a discharge
pipe. It is recommended that a tundish (not supplied) be installed in the discharge
pipe to give a visible indication that the valves are operating.
4.2
The discharge pipe must fall continuously from the valve outlets and be
unobstructed.
4.3
The pipe from the valves to the tundish should be 15mm o/dia minimum. From
the tundish to the point of discharge the pipe should be 22mm o/dia minimum and
have a resistance to flow equivalent to 9 metres of straight pipe. Long discharge
pipe runs should have an increased internal diameter.
4.4
The pipe material should be capable of conveying water/steam at 100
o
C.
4.5
The final discharge point should be in a safe, visible position.
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5.0 COMMISSIONING
5.1
Do not switch on the electrical supply until the unit has been filled with water and
checked for leaks.
5.2
Check that all installation, electrical and discharge pipe requirements have been
met.
5.3
Check that all water and electrical connections are tight.
5.4
Open a hot water tap, turn on mains water supply to the heater.
5.5
Allow unit to fill and leave hot tap running for a short while to purge any air and
flush out the pipework. Close the hot tap and check the system for leaks.
5.6
Manually test the operation of the Pressure (Expansion) Relief Valve and, if
fitted, the Temperature/Pressure Relief Valve. Ensure water flows freely from the
valve(s) and through the discharge pipes.
5.7
Switch on the electrical supply. The indicator light will illuminate during heating.
When the set temperature is reached the indicator light will go out.
5.8
The set temperature can be adjusted by rotating the shaft located on the Combined
Thermostat and Thermal Cut-out, clockwise increases the temperature. Access to
adjust the temperature is gained by removing the terminal cover
.
6.0 REMOVAL AND FITTING OF TERMINAL COVER
6.1
To remove the terminal cover use a large flat bladed screwdriver to relieve the
snaps located towards the front at either side of the cover. Gripping the cover at
the front, pull upwards.
6.2
To fit the cover, locate the hinge at the back. Slide the snaps into place. Apply
pressure to the front of the cover pushing back and down until it snaps securely
in place.