Tekmar 374 Universal Reset Control User Manual

- Data BrochureUniversal Reset Control 374D 37403/09 1 of 36 © 2009 D 374 - 03/09Universal Reset Control 374Two Mixing, Two Stage Boiler, DHW &a

© 2009 D 374 - 03/09 10 of 36 Section C1Domestic Hot Water (DHW)Section C2DHW with Low Temperature BoilersSection C: DHW OperationSection C1

11 of 36 © 2009 D 374 - 03/09DHW PumpPrimaryPumpMixSystemPumpDisableUsing ExternalWiringDHWPumpPrimaryPumpDHW MODE 4 - DHW in Primary / S

© 2009 D 374 - 03/09 12 of 36 Section C2: DHW with Low Temperature BoilersSETPOINTThe control can operate to satisfy the requirements of a s

13 of 36 © 2009 D 374 - 03/09BOILER TARGET DURING SETPOINTThe boiler target temperature during a setpoint demand is increased to at least

© 2009 D 374 - 03/09 14 of 36 MIX 2 DEMANDThe mix 2 demand allows the operation of the mixing 2 device to provide outdoor reset to the mix 2

15 of 36 © 2009 D 374 - 03/09MIXING TERMINAL UNITSWhen a terminal unit is selected, the control automatically loads the mixing design tem

© 2009 D 374 - 03/09 16 of 36 CAUTIONImproper installation and operation of this control could result in damage to the equipment and possib

17 of 36 © 2009 D 374 - 03/09Boiler DemandTo generate a Boiler Demand, a voltage between 24 V (ac) and 230 V (ac) must be applied across

© 2009 D 374 - 03/09 18 of 36 Mix 1 System Pump (Mix1 P2)The Mix1 P2 output terminal (13) is a powered output. When the relay in the control

19 of 36 © 2009 D 374 - 03/09DHW Pmp / Vlv ContactThe DHW Pmp / Vlv terminals (19 and 20) are an isolated output. There is no power avail

© 2009 D 374 - 03/09 2 of 36 User InterfaceThe 374 uses a Liquid Crystal Display (LCD) as the method of supplying information. You use the LCD in

© 2009 D 374 - 03/09 20 of 36 Unoccupied SwitchIf an external timer (tekmar Timer 032) or switch is used, connect the two wires from the ext

21 of 36 © 2009 D 374 - 03/09DHW DemandIf a DHW demand is used, measure the voltage between the DHW Dem and the Com Dem terminals (29 and

© 2009 D 374 - 03/09 22 of 36 Stage 2 / Setp Enable ContactIf an on / off boiler is connected to the Stage 2 / Setp Enbl. terminals (23 an

23 of 36 © 2009 D 374 - 03/09The control’s exterior can be cleaned using a damp cloth. Moisten the cloth with water and wring out prior t

© 2009 D 374 - 03/09 24 of 36 Rotate / OffThe Rotate / Off DIP switch selects whether or not the control is to provide Equal Run Time Rotati

25 of 36 © 2009 D 374 - 03/09View Menu (1 of 1)Outdoor Current outdoor air temperature as measured by the outdoor sensor. This item is on

© 2009 D 374 - 03/09 26 of 36 Adjust Menu (1 of 4)E1Mix 1 Mode Selects the mode of operation for mixing device 1.0 (off)1 (reset)Default =

27 of 36 © 2009 D 374 - 03/09Adjust Menu (2 of 4)E1Mix 2 Room Unoccupied The desired room air temperature during the unoccupied period fo

© 2009 D 374 - 03/09 28 of 36 Adjust Menu (3 of 4)ABoiler Terminal Unit The type of terminal units that are being used in boiler zones. This

29 of 36 © 2009 D 374 - 03/09Adjust Menu (4 of 4)D1Setpoint Mode Selects the Setpoint mode of operation.1 (parallel, no priority),2 (para

3 of 36 © 2009 D 374 - 03/09The following defined terms and symbols are used throughout this manual to bring attention to the presence of

© 2009 D 374 - 03/09 30 of 36 SETTING THE TIMEStep OnePress and release the Menu button until the TIME menu is reached.Step TwoPress the Ite

31 of 36 © 2009 D 374 - 03/09Schedule Menu (1 of 1)SETTING THE SCHEDULEA schedule allows the timer to automatically change between two pr

© 2009 D 374 - 03/09 32 of 36 The control has a built-in test routine that is used to test the main control functions. The control continual

33 of 36 © 2009 D 374 - 03/09TroubleshootingWhen troubleshooting any heating system, it is always a good idea to establish a set routine

© 2009 D 374 - 03/09 34 of 36 The control was unable to read a piece of information stored in its memory. Because of this, the control was r

35 of 36 © 2009 D 374 - 03/09Error Messages (2 of 2)The control is no longer able to read the boiler sensor due to an open circuit. When

Technical Data 36 of 36Product design, software and literature are Copyright © 2009 by:tekmar Control Systems Ltd. and tekmar Control Systems, Inc.Al

© 2009 D 374 - 03/09 4 of 36 Section AGeneralOperationPage 4 - 6Section BBoilerResetPage 6 - 9Section CDHW OperationPage 10 - 12Sequence of Opera

5 of 36 © 2009 D 374 - 03/09Low Mass Radiant (2)This type of radiant heating system is either attached to the bottom of a wood sub-floor,

© 2009 D 374 - 03/09 6 of 36 EXERCISINGThe control has a built-in exercising feature, which ensures that each pump or valve is operated at least

7 of 36 © 2009 D 374 - 03/09BOILER CHARACTERIZED HEATING CURVEThe boiler(s) have a Boiler Characterized Heating Curve determined by the f

© 2009 D 374 - 03/09 8 of 36 Boiler MassThe boiler mass setting allows the installer to adjust the control to the thermal mass of the type of hea

9 of 36 © 2009 D 374 - 03/09Increasing LoadTimeDifferentialOnOffTemperature fall Temperature rise TimeDesired temperature160°F (71°C)Differe