10Installation and ServicingSECTION 1 - GENERAL1.1 INTRODUCTIONThe Zanussi Ultra+ Combi range of boilers are wall mounted, fullsequence, automatic spark ignition, low water content, fannedflue, high efficiency, condensing, combination gas boilers.Note. Due to the high efficiency of the boiler a plume of watervapour will form at the terminal during operation.Central heating (CH) output is fully modulating with a range of:30 6.1 to 24.2kW35 7.1 to 24.2kWInstantaneous domestic hot water (DHW) output is also fullymodulating with a maximum of :30 30.3kW35 35.3kWThe boiler is supplied fully assembled with DHW plate heatexchanger, diverter valve, circulating pump, pressure gauge,safety valve and CH expansion vessel.Variable CH and DHW temperature controls are fitted on the usercontrol and the boiler features a DHW preheat facility.The boiler includes as standard:- Automatic bypass- Boiler frost protection- Daily pump and diverter valve exercise.The boiler casing is of white painted mild steel with a whitepolymer front panel.The boiler temperature controls are visibly located in the controlpanel on the front of the boiler.The heat exchanger is manufactured from cast aluminium.The boiler is suitable for connection to fully pumped, sealedheating systems ONLY. Adequate arrangements for completelydraining the system by provision of drain cocks MUST be providedin the installation pipework.Pipework from the boiler is routed downwards.Data PlateThe boiler model and serial number can be located on thebottom of the boiler casing, shown in Section 1.16 - Water & GasConnection Diagram.1.2 OPERATIONWith no demand for CH, the boiler fires only when DHW is drawnoff, or periodically for a few seconds without any DHW draw-off,in order to maintain the DHW plate heat exchanger in a heatedcondition. This only occurs if the “PREHEAT” button is pressedand the display reads “HOT WATER PREHEAT ON”.When there is a demand for CH, the heating system is suppliedat the selected temperature of between 30 o C and 80 o C, untilDHW is drawn off. The full output from the boiler is then directedvia the diverter valve to the plate heat exchanger to supply anominal DHW draw-off of30 12.4 l/min at 35ºC temperature rise.35 14.5 l/min at 35ºC temperature rise.The DHW draw off rate specified above is the nominal that theboiler flow regulator will give. Due to system variations andseasonal temperature fluctuations DHW flow rates/temperaturerise will vary, requiring adjustment at the draw off tap.At low DHW draw-off rates the maximum temperature mayexceed 65ºC.The boiler features a comprehensive diagnostic system whichgives detailed information on the boiler status when operating,and performance of key components to aid commissioning andfault finding.1.3 SAFE HANDLINGThis boiler may require 2 or more operatives to move it to itsinstallation site, remove it from its packaging base and duringmovement into its installation location. Manoeuvring the boilermay include the use of a sack truck and involve lifting, pushingand pulling.Caution should be exercised during these operations.Operatives should be knowledgeable in handling techniqueswhen performing these tasks and the following precautionsshould be considered:• Grip the boiler at the base.• Be physically capable.• Use personal protective equipment as appropriate, e.g.gloves, safety footwear.During all manoeuvres and handling actions, every attemptshould be made to ensure the following unless unavoidable and/or the weight is light.• Keep back straight.• Avoid twisting at the waist.• Avoid upper body/top heavy bending.• Always grip with the palm of the hand.• Use designated hand holds.• Keep load as close to the body as possible.• Always use assistance if required.