Supplied By www.heating spares.co Tel. 0161 620 6677204 3 N LN L 44.8 Controls4.8.1 External electrical controlsThe boiler terminals 3,4 and 5 are forconnecting external controls such as atime switch and/or room thermostat.Terminals 3 and 4 are linked togetherwhen the boiler is supplied. If externalcontrols are used, this link must beremoved, and the controls connectedacross terminals 3 and 4.Terminal 5 is an additional neutralconnection for external neutrals suchas from the anticipator of a roomthermostat.Refer to Section 4.8.2 for fullconnection details.4.8.2 Connection of external electricalcontrols4.8.2.1 Connection details forprogrammable thermostat and boilerterminal strip (refer to fig. 29).Fig. 29 shows the connection detailswhere a programmable thermostat(time switch with built-in roomthermostat) is used to control theboiler. (Important: The arrowednumbers indicate connection into therelevant terminal in the boiler terminalstrip).4.8.2.2 Connection details forexternal time switches and boilerterminal strip (refer to fig 29a).Fig. 29a shows the connection detailswhere a time switch is used without aroom thermostat to control the boiler.(Important: The arrowed numbersindicate connection into the relevantterminal in the boiler terminal strip).If a room thermostat is to be connectedin addition to a time switch the wirebetween the time switch 'ON' terminaland boiler terminal 4 should be brokenby the contacts of the room thermostat(see Schematic layout, fig. 30).If a frost thermostat is to be fitted itshould be connected in parallel acrossterminals 3 and 4.4.8.2.3 Vaillant optional Plug-in timerAccessoriesRefer to the instructions supplied withthe optional plug in timer accessoriesfor connection details.ÕÕÕÕACL DraytonLifestyleLP711ACL DraytonSwitchmaster 300(Please note: Remove Link N-2 and L-4)Grässlin TowerchronDt71, T200lHoneywellST6100HoneywellST7000B(Battery operated)Horstmann425 CoronetChannel Plus, H17, H11Landis & GyrRWB100, 152, 170Potterton MysonEP400l, EP500lDanfoss Randall103, 103E, 103E7Danfoss RandallSet 1E, TS975f i g .f i gGW 409/0Boiler Terminal StripE N L 1 2 3 4 5 6ON OFFN L 4 3ÕÕÕÕE N L 1 2 3 4 5 6ON OFFN L 4 3ÕÕÕÕÕN L 1 2 3 4 5 EOFF ONN L 3 4ÕÕÕÕÕÕÕÕÕ ÕN L 1 2 3 41 2 3 E 5 6ONN L 3 4ÕÕÕÕN L 1 2 3 4OFF ONN L 4 3ÕÕÕÕN L 1 2 3 4ONN L 3 4ÕÕÕÕN L 1 2 3 4ONN L 3 4ÕÕÕÕN L 1 2 3 43 4ÕÕL 2 3 4OFF ONVaillant Calotrol(VRT 9083 and VRT 9084)ACL DraytonDigistat 2 and 3ACL DraytonPT110, PT170ACL DraytonLifestyleCT171, CT172,PT271, PT371Danfoss RandallTP2, TP3, TP4, TP5HoneywellCM51, CM41Landis & GyrREV 10 and 21Potterton MysonPot 1f i gN L 4 3ÕÕÕÕN L 1 2 3 4N L 3ÕÕÕN L 1 2 3 4OFF ON3 4 5ÕÕÕÕ2 L 1 N COFF ONN L 3 4ÕÕÕÕ1 2 3 43 4ÕÕ1 2 33 4ÕÕ1 2 33 4ÕÕA B C3 4ÕÕQ1 Q2Connection detail for room thermostat and time switchConnection details for time switchConnection details for programmable thermostats