Tekmar 420 Boiler Reset Module User Manual

D 42008/07- Data BrochureBoiler Reset Module 4201 of 24 © 2007 D 420 - 08/07• • tN4 Compatible• • Boiler Outdoor Reset• • Single On-Off or Modulati

© 2007 D 420 - 08/07 10 of 24Item Field Range Access DescriptionInS (Installer)Ad (Advanced)InSAdACCESS LEVELThe access level that is to be used by th

11 of 24 © 2007 D 420 - 08/07Step 1 The primary pump turns on and remains on for the rest of the test sequence.Step 2 The boiler contact is closed t

© 2007 D 420 - 08/07 12 of 24tekmarNet®4 Communication Section AtekmarNet®4 (tN4) communicates between tN4 devices (thermostats, Reset Module and Exp

13 of 24 © 2007 D 420 - 08/07Terminal UnitThere is a terminal unit setting for each tN4 bus. The Terminal Unit setting is found in the Adjust menu.Hyd

© 2007 D 420 - 08/07 14 of 24Boiler Characterized Heating CurveTerminal UnitBoiler DesignBoiler IndoorOutdoor DesignDecreasing Outdoor Temperatures In

15 of 24 © 2007 D 420 - 08/07Boiler MaximumThe boiler maximum is the highest temperature that the control is allowed to use as a boiler target tempera

© 2007 D 420 - 08/07 16 of 24In some cases, multiple boilers may be required. In these cases, the 420 allows for a connection to a tekmar Boiler Contr

17 of 24 © 2007 D 420 - 08/07Zone Load Shedding Section EDomestic Hot Water Temperature Operation Section FDHW DemandA powered DHW Demand is require

© 2007 D 420 - 08/07 18 of 24DHW MODE 2 - DHW in Parallel with PriorityWhen a DHW Demand is present, the DHW Pump contact closes. The primary pump (P1

19 of 24 © 2007 D 420 - 08/07DHW with Low Temperature Boilers Section GIf DHW heating is to be incorporated into a low temperature system such as a r

© 2007 D 420 - 08/07 2 of 24Table of ContentsTable of Contents ...2Display and DIP Switches .

© 2007 D 420 - 08/07 20 of 24Setpoint Mode 3 – Setpoint in Primary / SecondaryWhenever a setpoint demand is present, the primary pump (P1) is turned o

21 of 24 © 2007 D 420 - 08/07Error MessagesLocal Errors and Device ErrorsError messages are used to indicate a problem somewhere in the system. There

© 2007 D 420 - 08/07 22 of 24Error Message DescriptionADJUST ERRORThe control failed to read the Adjust menu settings, and reloaded the factory defaul

23 of 24 © 2007 D 420 - 08/07Symptom Possible Causes Corrective ActionBoiler does not fire when there is a DHW or Setpoint DemandNo voltage present on

tekmar Control Systems Ltd., Canadatekmar Control Systems, Inc., U.S.A.Head Office: 5100 Silver Star RoadVernon, B.C. Canada V1B 3K4(250) 545-7749 Fa

3 of 24 © 2007 D 420 - 08/07Access LevelBoil On-Off / ModThe Boil On-Off / Mod DIP switch selects whether the control operates an On-Off boiler or the

© 2007 D 420 - 08/07 4 of 24PUMPDisplays when the primary or mixing pump is in operation.BURNERDisplays when the burner contact is closed.LOCKDisplays

5 of 24 © 2007 D 420 - 08/07User InterfaceUse the User Interface available on the Liquid Crystal Display (LCD) to setup and monitor the operation of t

© 2007 D 420 - 08/07 6 of 24View Menu (1 of 1) Item Field Range Access Description-76 to 149°F(-60.0 to 65.0°C)InSAdOUTDOOR SECTION BCurrent outdoor

7 of 24 © 2007 D 420 - 08/07Item FieldRangeAccess Description-60 to 45°F(-51.0 to 7.0°C)Default = 10°F(-12.0°C)InSAdOUTDOOR DESIGN SECTION BThe design

© 2007 D 420 - 08/07 8 of 24Item FieldRangeAccess DescriptionAu, 2 to 42°F(Au, 1 to 23.5°C)Default = AuAdBOILER DIFFERENTIAL SECTION CThe temperature

9 of 24 © 2007 D 420 - 08/07Item FieldRangeAccess Description100 to 220°F(38.0 to 104.5°C)Default = 180°F (82.0°C) AdDHW EXCHANGE OCCUPIED SECTION FTh