DORCHESTER DR-LA 110, User Manual

Page: 57 / 64

Introduction
Instruction manual DR-LA 57
s
9 Maintenance
9.1 Introduction
c
Note
Maintenance may only by carried out by an approved service and
maintenance engineer.
At each service, the water heater undergoes maintenance both on the water
side and on the gas side. The maintenance should be carried out in the following
order.
1.
Preparing for maintenance ;
2. Water-side maintenance ;
3. Gas-side maintenance ;
4. Finalising maintenance .
n Caution
Before ordering spare parts, take a moment to write down the water heater
type and model and the full serial number of the water heater. Only by
ordering with this information can you be sure to receive the correct spare
parts. These details can be found on the rating plate.
9.2 Preparing for
maintenance
To test whether all components are still working properly, you should complete
the following steps:
1. Put the ON/OFF switch on the control panel to position 0 .
2. Set the control thermostat (note the original setting) to the highest position
and put the ON/OFF switch back to position I .
3. If there is no heat demand, draw some hot water off to initiate a heat
demand.
4. Check whether the heating cycle runs correctly. See paragraph 7.4 Heating
cycle .
5. Set the control thermostat back to the original setting and put the ON/OFF
switch back to position I .
6. Check the supply and burner pressures and adjust these, where necessary.
See paragraph 3.11 Checking the supply pressure and burner pressure .
7. Check that all components of the flue gas system are properly attached.
8. Test the operation of the expansion valve of the cold supply setup. The water
should spurt out.
9. Test the overflow operation of the T&P valve. The water should spurt out.
10. Check the drain pipes from the discahrge points of any valve and remove
any lime buildup that may be present.
11. Drain the water heater. See paragraph 4.3 Draining the water heater .
s