Maintenance - andrews CWH30/100 Installation Manual, Operation And Maintenance Manual

SECTION 7
Fig. 14
Flushing Point
36

MAINTENANCE

At least once a year the following works must be carried out:
1. Check the CO percentage and adjust if necessary, see page 32.
2
2. Check the output at full load by measuring the gas usage. If this deviates more than
15% from the nominal value (see Section 2, Technical Details) then this is an indication
of dirt or blockages in the flue gas extraction channel, the air supply channel or the
condensation extractor.
3. Switch off the electricity supply. Check the condensation extraction and rinse the
condensation tray and condensation extraction with clean pipe water. An opening has
been provided for this on the top of the condensation tray, see Fig.14. When no more
impurities come out then the condensation extraction is clean.
4. Check the ionisation electrode. This must be straight and clean (light residue is normal).
5. Flush the water heater tank by opening the drainage tap. Let water flow out of the
water heater until no more chalk residue comes out with the water. In areas with hard
water it is necessary to flush out the water heater more frequently.
6. If the water heater is to be drained for any reason, first take the water heater out of
operation and then proceed as follows:
a. Turn off the water tap in the cold water supply.
b. Open one of the warm water taps that can be found at a point higher than the
water heater in order to bleed the warm water pipe section. If the water heater is
set up above the level of the drainage points it will be necessary to open the
warm water connection to let the appliance run empty.
c. Open the drainage tap of the water heater, so the appliance runs empty. Be
careful, the water flowing out can be very hot!
7. The storage tank should be inspected annually and cleaned if required. To gain access,
first drain the tank as above, disconnect any pipework connections to allow removal of
the tank cover, including the pipes from the T&P valve (The valves should be left in
position in the inspection cover), remove sixteen M10 bolts and washers securing the
cover at the top. Lift off the cover, retain the O ring seal for refitting, alternatively a
new seal may be required. When refitting the cover locate the O ring in the groove
and fasten cover using the bolts and washers. Do not over tighten, the torque setting
used should be 60Nm.