COMBI A - Instruction Manual

13. Electrical

13. Electrical connections (continued) 13.1 Fitting the Digital Programmer The boiler is supplied with a factory fitted mechanical time clock, to fit the optional digital programmer it is necessary to proceed as follows; (this should only be carried out by a competent engineer) - Isolate the electrical supply to the appliance; - Remove the front panel as described in Section 18.1.1; - Remove the mechanical clock on the right hand side (Fig. 31) and pull out the 4 wires (Fig. 32); NOTE: THE WIRES MAY BE TUCKED BEHIND THE ELECTRICAL COVER. - Connect the clock wires as follows; MECHANICAL MODEL (Fig. 33) Red Wire - Contact 1 Black Wire - Contact 2 Black Wire - Contact 3 Grey Wire - Contact 5 Fig. 31 NOTE: THE TWO BLACK WIRES ON CONTACTS 2 & 3 CAN BE REVERSED DIGITAL MODEL (Fig. 34) Red Wire - Contact 1 Black Wire - Contact 2 Grey Wire - Contact 3 NOTE: SECOND BLACK WIRE IS NOT CONNECTED. - Push the clock back into the panel and refit the casing panel (Fig. 35). Fig. 32 Fig. 33 5 4 3 2 1 G B R Fig. 34 Fig. 35 28

14. Commissioning and testing 14.1 Initial preparation MTS (GB) Limited support the initiative. In Sections 24 and 25 (pages 60 and 61) of this manual the Commissioning Checklist and Service Interval Record can be found. It is important that this is completed in the presence of your customer, they are shown how to use it, and it is signed by them. Please instruct your customer that they must have this manual with them whenever they contact a service engineer or us. Preliminary electrical system checks to ensure electrical safety must be carried out by a competent person i.e. polarity, earth continuity, resistance to earth and short circuit. FILLING THE HEATING SYSTEM: Remove the front casing panel and lower the control panel as described in Section 18.1 (page 43). Open the central heating flow and return cocks supplied with the connection kit; Unscrew the cap on the automatic air release valve one full turn and leave open permanently; Close all air release valves on the central heating system; Gradually open the valves at the filling point (filling loop) until water is heard to flow, do not open fully; Open each air release tap starting with the lowest point and close them only when clear water free of air is visible; Purge the air from the pump by unscrewing the pump plug anti-clockwise, also manually rotate the pump shaft in the direction indicated by the pump label to ensure the pump is free; Refit the pump plug; Continue filling the system until at least 1.5 bar registers on the pressure gauge; Inspect the system for water soundness and remedy any leaks discovered. FILLING OF THE DHW SYSTEM: Close all hot water draw off taps; Open the cold water inlet cock supplied with the connection kit; Slowly open each draw off tap and close them only when clear water, free of bubbles, is visible. GAS SUPPLY: Inspect the entire installation including the gas meter and test for soundness. The entire installation should be in accordance with the relevant standards. In GB this is BS 6891 and in IE this is the current edition of I.S.813. The connection on the the appliance is a 15mm copper tail located at the rear of the gas service cock (39 Fig. 2 - page 5) If the gas supply serves other appliances, ensure that an adequate supply is available both to the boiler and the other appliances when they are in use at the same time. Pipe work must be of an adequate size. Pipes of less than 22mm should not be used. Open the gas cock (supplied with the connection kit) to the appliance and check the gas connection on the appliance for leaks. WATER TREATMENT: The boiler is equipped with a stainless steel heat exchanger. The detailed recommendations for water treatment are given in BS 7593:1992 (Treatment of water in domestic hot water central heating systems); the following notes are given for general guidance; If the boiler is installed on an existing system, any unsuitable additives must be removed; Under no circumstances should the boiler be fired before the system has been thoroughly flushed; the flushing procedure must be in line with BS7593:1992. Firstly fill the central heating system with the power off, and flush through cold, fill the central heating system again, adding a flushing detergent, run the boiler on central heating until it reaches its operating temperature and flush the system, refill the system with a suitable corrosion inhibitor, NOTE: FAILURE TO CARRY OUT THE FLUSHING PROCEDURE WILL RESULT IN THE WARRANTY BECOMING VOID. 14.2 Initial start-up The checks to be run before initial start-up are as follows: 1. Make sure that: - The screw on the automatic air valve has been loosened when the system is full; - If the water pressure in the system is below 1.0 bar, bring it up to the appropriate level; - Ensure that the gas cock is closed; - Make sure that the electrical connection has been made properly and that the earth wire is connected to an efficient earthing system; - Supply power to the boiler by pushing the on/off button 26 (Fig. 1) the green led indicator light will illuminate; - Turn the central heating control knob 29 (Fig. 1) to maximum and switch the time clock (if fitted) to constant and turn up the room thermostat; - After 7 seconds, the boiler will signal a shutdown due to ignition failure. Leave the boiler as it is until all the air has been bled from the system; - Loosen the cap on the head of the pump to eliminate any air pockets; - Repeat the procedure for bleeding the radiators of air; - Open the hot water taps for a short period; - Check the system pressure and, if it has dropped, open the filling loop again to bring the pressure back up to 1.0 bar; 2. Make sure that all radiator valves are open; 3. Turn on the gas cock and check the seals on the connections with any approved soap solution and eliminate any leaks; 4. Press the reset button 28 (Fig. 1) the boiler will re-attempt ignition. If the burner does not light the first time, wait 1 minute and repeat the procedure; 5. Check the minimum and maximum CO2 values and gas rates;- Adjust if necessary as indicated in Section 14.3 (page 30). 29