Tekmar 257 DHW Control Manuel d'utilisateur

1 of 12 © 2009 D 257 - 03/09D 25703/09- Data BrochureDHW Control 257The DHW Control 257 is used for dedicated domestic hot water systems. The c

© 2009 D 257 - 03/09 10 of 12 Program Menu Item Field Range Description Actual SettingStage Mode DelayTarget DHWDifferentialDHW70 to 190°F(21 to 8

11 of 12 © 2009 D 257 - 03/09Field TestTo test the control, push and hold the up button for 3 seconds while in the default menu. While in

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 Fax

© 2009 D 257 - 03/09 2 of 12 How to Use the Data BrochureThis brochure is organized into three main sections.They are: 1) Sequence of Operation,

3 of 12 © 2009 D 257 - 03/09▼POINTERDisplays the control operation as indicated by the text.HEAT RELAYDisplays when the HEAT 1 relay is closed

© 2009 D 257 - 03/09 4 of 12 Sequence of OperationWhen the DHW Control 257 is powered up all LCD segments are displayed for 2 seconds followed by

5 of 12 © 2009 D 257 - 03/09This function rotates the firing sequence of the two boilers based on the accumulated running hours of each stage.

© 2009 D 257 - 03/09 6 of 12 Step Three — Rough-in WiringThe wiring terminates in the two wiring chambers on the control. Determine whether the l

7 of 12 © 2009 D 257 - 03/09Test the OutputsHeat 1 and Heat 2 Make sure power is off to the boiler circuits and connect the TT contacts on the

© 2009 D 257 - 03/09 8 of 12 DIP Switch SettingsOff | On - RotateThe Off | On – Rotate DIP switch is used to turn boiler rotation on or off. When

9 of 12 © 2009 D 257 - 03/09DEFAULT MENUDefault Menu Item Field Range DescriptionStage Mode DelayTarget DHWDifferentialDHW-60 to 255°F(-51 to 1