- Data Brochure D 261 Boiler Control 261 03/09 The Boiler Control 261 is designed to control two separate on / off boiler stages (or one low / high fire) in order to provide outdoor reset or setpoint operation. The control includes a Liquid Crystal Display (LCD) to view system status and operating information.
How To Use The Data Brochure This brochure is organized into four main sections. They are: 1) Sequence of Operation, 2) Installation, 3) Control Settings, and 4) Troubleshooting. The Sequence of Operation section has three sub-sections. We recommend reading Section A: General Operation of the Sequence of Operation, as this contains important information on the overall operation of the control. Then read the sub-sections that apply to your installation.
Display Item Field Displays an abbreviated name of the selected item Number Field Displays the current value of the selected item OUTDR DSGN DIFF BOIL TARGET MIN MAX ROOM WWSD INDR UNOCC Terminal Unit VIEW ADJUST °F °C min Displays the current menu 12 Boiler Demand Setpoint Fire Delay Setpoint Demand { Status Field Displays the current status of the control’s inputs, outputs and operation Menu Field Buttons Selects Menus, Items and adjusts settings Item Symbol Description 12 OCC Pump Display
Sequence of Operation Section A General Operation Page 4 Section B Boiler Reset Page 5-8 Section C Setpoint Page 8 Section A — General Operation POWERING UP THE CONTROL When the Boiler Control 261 is powered up, the control displays the control type number in the LCD for 2 seconds. Next, the software version is displayed for 2 seconds. Finally, the control enters into the normal operating mode and the LCD defaults to displaying the current outdoor air temperature.
Section B: Boiler Reset Section B1 General Section B2 Installer Section B3 Advanced Section B1: General BOILER DEMAND A boiler demand is required in order for the 261 to provide heat to the heating system. A boiler demand is generated by applying a voltage between 24 and 240 V (ac) across the Boiler Demand terminals (1 and 2). Once voltage is applied, the Boiler Demand pointer is displayed in the LCD. If the 261 is not in WWSD, the 261 closes the Boil Pmp contact.
Section B2: Installer BOIL DSGN The OUTDR DSGN is the outdoor air temperature that is the typical coldest temperature of the year where the building is located. This temperature is used when doing the heat loss calculations for the building. If a cold outdoor design temperature is selected, the boiler supply temperature rises gradually as the outdoor temperature drops. If a warm outdoor design temperature is selected, the boiler supply temperature rises rapidly as the outdoor temperature drops.
Fancoil (3) A fancoil terminal unit or air handling unit (AHU) consists of a hydronic heating coil and either a fan or blower. Air is forced across the coil at a constant velocity by the fan or blower, and is then delivered into the building space. Default values: BOIL DSGN = 190°F (88°C), BOIL MAX = 210°F (99°C), BOIL MIN = 140°F (60°C) Fin–tube Convector (4) A convector terminal unit is made up of a heating element with fins on it.
Boiler Contact Closes Boiler Fires FIRE DELAY (Fire Delay) Boiler Temperature The Fire Delay is the delay time that may occur between the time that the 261 closes a stage contact, and the burner fires for that stage. This delay is usually the result of burner pre-purge, or other forms of time delay built into the burner’s safety circuits.
Installation CAUTION Improper installation and operation of this control could result in damage to the equipment and possibly even personal injury. It is your responsibility to ensure that this control is safely installed according to all applicable codes and standards. This electronic control is not intended for use as a primary limit control. Other controls that are intended and certified as safety limits must be placed into the control circuit.
3 4 Setpoint Demand Setpoint Demand To generate a setpoint demand, a voltage between 24 V (ac) and 240 V (ac) must be applied across the Setpoint Demand terminals (3 and 4). 24 to 240 V (ac) Output Connections 7 5 6 Power Boil L N Pmp Boiler Pump Contact (Boil Pmp) 8 Boiler pump N The boiler pump output terminal (7) on the 261 is a powered output. When the relay contact in the 261 closes, 120 V (ac) line (L) is provided to the Boil Pmp terminal (7) from the Power L terminal (5).
Unoccupied Switch 13 14 UnO Com Sw If an external timer (tekmar Timer 032) or switch is used, connect the two wires from the external switch to the UnO Sw and Com terminals (13 and 14). When these two terminals are shorted together, the control registers an unoccupied signal. Timer switch STEP FIVE TESTING THE WIRING Each terminal block must be unplugged from its header on the control before power is applied for testing. To remove a terminal block, pull it straight down from the control.
Test The Outputs 5 6 7 8 Power Boil L N Pmp N Boiler Pump (Boil Pmp) If the boiler pump is connected to the Boil Pmp terminal (7), make sure power to the terminal block is off, and install a jumper between the Power L and the Boil Pmp terminals (5 and 7). Install a second jumper between Power N and N terminals (6 and 8). When power is applied to the Power L and Power N terminals (5 and 6), the boiler pump should start.
Quick Setup To enter the installer programming mode, set the Advanced / Installer DIP switch to Installer. Access the ADJUST menu by pressing and holding simultaneously for 1 second, the Item, The display will now show the word ADJUST in the top right corner. ADJUST °F ROOM and buttons (all three at same time). The ROOM OCC adjustment is the first item displayed. Use the or button to set the ROOM temperature. The ROOM OCC setting is set to the desired room air temperature during the occupied (Day) mode.
Se ct i In on st a Ad ller va nc ed View Menu (1 of 1) Display OUTDR Description Range VIEW °F Current outdoor air temperature as measured by the outdoor sensor. This is also the default display for the control. -67 to 149°F (-55 to 65°C) B1 B3 Current boiler supply water temperature as measured by the boiler sensor. 14 to 266°F (-10 to 130°C) B1 B3 C Target boiler supply is the temperature the control is currently trying to maintain at the boiler sensor.
Se ct i In on st a Ad ller va nc ed Adjust Menu (2 of 2) Display DSGN ADJUST °F BOIL MAX The design supply water temperature used in the heat loss calculation for the heating system. 70 to 220°F (21 to 104°C) B3 The maximum boiler target supply water temperature. 120 to 225°F (49 to 107°C) B3 The minimum temperature allowed for the boiler target temperature.
Testing the Control The Boiler Control 261 has a built-in test routine which is used to test the main control functions. The 261 continually monitors the sensors, and displays an error message whenever a fault is found. See the following pages for a list of the 261’s error messages and possible causes. When the Test button is pressed, the test light is turned on. The individual outputs and relays are tested in the following test sequence.
Troubleshooting When troubleshooting any heating system, it is always a good idea to establish a set routine to follow. By following a consistent routine, many hours of potential headaches can be avoided. Below is an example of a sequence that can be used when diagnosing or troubleshooting problems in a hydronic heating system. Establish the Problem Establish the problem. Get as much information from the customer as possible about the problem.
Error Messages VIEW The control was unable to read a piece of information from its EEPROM. This error can be caused by a noisy power source. The control will load the factory defaults and stop operation until all the settings are verified. OUTDR VIEW The control is no longer able to read the outdoor sensor due to a short circuit. In this case the control assumes an outdoor temperature of 32°F (0°C) and continues operation. Locate and repair the problem as described in the Data Brochure D 070.
Notes 19 of 20 Copyright © D 261 - 03/09
Technical Data Boiler Control 261 Two Stage Boiler & Setpoint Literature Control Packaged weight Dimensions Approvals Ambient conditions — — — — — — Power supply Relays Demands Sensors included — — — — Optional devices — D 261, A 261’s, D 001, D 070. Microprocessor PID control; This is not a safety (limit) control. 3.0 lb. (1340 g), Enclosure A, blue PVC plastic 6-5/8” H x 7-9/16” W x 2-13/16” D (170 x 193 x 72 mm) CSA C US, CSA 22.2 No 24 and UL 873, meets class B: ICES & FCC Part 15.
