Ideal Boilers Optia HE 9 Installation And Servicing Instructions

30 Optia HE - Installation & ServicingINSTALLATIONNotes.1. Some earth wires are omitted forclarity. Ensure proper earth continuitywhen wiring.2. Numbering of terminals onthermostats is specific to themanufacturer.3. This is a fully controlled system - setthe boiler thermostat to maximum.4. Switchmaster valve has grey andorange auxiliary switch leads but thegrey wire must be connected to thelive supply.45 TWO SPRING CLOSED VALVEPumped onlygy greyy/g yellow/greenor orangev violetpk pinkLEGENDb bluebk blackbr brownr redy yelloww white46 FROST PROTECTIONCentral heating systems fitted wholly inside the house do notnormally require frost protection as the house acts as a'storage heater' and can normally be left at least 24 hrs. withoutfrost damage. However, if parts of the pipework run outsidethe house or if the boiler will be left off for more than a day orso, then a frost thermostat should be wired into the system.This is usually done at the programmer, in which case theprogramme selector switches are set to OFF and all othercontrols MUST be left in the running position.The frost thermostat should be sited in a cold place but whereit can sense heat from the system.Wiring should be as shown, with minimal disturbance to otherwiring of the programmer.Designation of the terminals will vary but the programmer andthermostat manufacturer's leaflets will give full details.If a boiler is installed in a garage it may be necessary to fit apipe thermostat.Diagram A shows a double pole frost thermostat, which shouldsuffice for all systems which do not use the OFF terminals ofthe programmer.Diagram B shows a 'change-over' frost 'stat', which will covermost systems which do use CH OFF. If, however, on such asystem the HW pipework is in an isolated part of the house, asecond frost 'stat may be used to protect it. If in doubt, ask yourinstaller for advice.INSTALLATION