- Data Brochure D 270 Boiler Control 270 08/10 The tekmar Boiler Control 270 can control the supply water temperature from a single modulating boiler based on outdoor temperature or domestic hot water requirements. A large easy to read display provides current system temperatures and operating status.
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) Testing and Troubleshooting. The Sequence of Operation section has six sub-sections. We recommend reading Section A: General 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 Number Field Displays the current value of the selected item Menu Field Displays the current menu Boiler Demand DHW Demand Modulation DHW Priority Override Item Field Displays an abbreviated name of the selected item Status Field Displays the current status of the control's inputs, outputs and operation Buttons Selects Menus, Items and adjust settings Symbol Description Burner Displays when Relay 1 is turned on. Warning Displays when an error exists or when a limit has been reached.
Definitions The following defined terms and symbols are used throughout this manual to bring attention to the presence of hazards of various risk levels, or to important information concerning the life of the product. - Warning Symbol: Indicates presence of hazards which can cause severe personal injury, death or substantial property damage if ignored.
EXERCISING The control has a built-in exercising feature that is selected through the Exercise / Off DIP switch. To enable the exercising feature set the Exercise / Off DIP switch to Exercise. If exercising is enabled, the control ensures that each pump is operated at least once every 3 days. If a pump has not been operated at least once every 3 days, the control turns on the output for 10 seconds. This minimizes the possibility of the pump seizing during a long period of inactivity.
MODULATION The Boiler Control 270 provides a modulating output signal to operate a single modulating boiler. The control first closes the boiler contact on to ignite the ignition sequence. The boiler is then modulated from the minimum modulation using Proportional, Integral and Derivative (PID) logic in order to satisfy the boiler target temperature. MOTOR SPEED The Motor Speed is the amount of time the boiler requires to go from 0% modulation to 100% modulation.
To calculate the Maximum Modulation, use the following formula: For 0 to 10 V (dc): Maximum Modulation = 0 V (dc) – Boiler’s Maximum Input Signal x 100% 0 – 10 V (dc) For 2 to 10 V (dc): Maximum Modulation = 2 V (dc) – Boiler’s Maximum Input Signal x 100% 2 – 10 V (dc) Example: A boiler’s input signal range is 2 to 9 V (dc). The 270 control has an output signal range of 2 to 10 V (dc).
Section C: Pump Operation PRIMARY PUMP OPERATION The primary pump operates under the following conditions: • A boiler demand is present and the control is not in Warm Weather Shut Down (WWSD). • A DHW demand is present and DHW MODE is set to 3 or 4. DHW Pump Primary Pump Primary Pump Purge Boiler Sensor After a demand is removed, the control continues to operate the primary pump for a period of time.
CHARACTERIZED HEATING CURVE Boiler Characterized Heating Curve BOIL DSGN BOIL MAX 190 (88) 170 (77) 150 (66) BOIL MIN 130 (54) OUT DSGN 110 (43) BOILER DESIGN TEMPERATURE The boiler design supply temperature is the supply water temperature required to heat the building when the outdoor air temperature is as cold as the outdoor design temperature.
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. Fin-Tube Convector (4) A convector terminal unit is made up of a heating element with fins on it. This type of terminal unit relies on the natural convection of air across the heating element to deliver heated air into the space.
DHW Pump DHW Mode 1 - DHW in Parallel no Priority Primary Pump When a DHW Demand is present, the DHW Pmp / Vlv contact (terminals 7 and 8) closes. The primary pump contact does not turn on, but may operate based on a boiler demand. Boiler Pump DHW Pump DHW Mode 2 - DHW in Parallel with Priority Primary Pump When a DHW Demand is present, the DHW Pmp / Vlv contact (terminals 7 and 8) closes and the primary pump contact is opened.
CONDITIONAL DHW PRIORITY The Conditional DHW Priority Override applies to DHW MODE 2 and Boiler Minimum is not set to OFF. If the boiler supply temperature is maintained at or above the required temperature during DHW generation, this indicates that the boiler has enough capacity for DHW and possibly heating as well. As long as the boiler supply temperature is maintained near its target, DHW and heating occurs simultaneously.
DHW MODE 4 OPERATION In DHW MODE 4, the space heating zones must be prevented from coming on during DHW demands using external wiring. This can be done using an external relay to remove power from zone pumps or zone valves while a DHW Demand is present. This external relay is interlocked with the DHW Pmp / Vlv contact. During a DHW Demand, the control closes the primary pump (Prim P1) contact and the DHW Pmp / Vlv contact.
STEP FOUR ELECTRICAL CONNECTIONS TO THE CONTROL General The installer should test to confirm that no voltage is present at any of the wires. Push the control into the base and slide it down until it snaps firmly into place. 5 6 Powered Input Connections Power N L 115 V (ac) Power 115 V (ac) Connect the 115 V (ac) power supply to the Power L and Power N terminals (5 and 6). This connection provides power to the microprocessor and display of the control.
Modulation Output The Modulation Output terminals (11 and 12) provide a 0 to 10 V (dc) or a 2 to 10 V (dc) output to the boiler. If a 0 to 20 mA or a 4 to 20 mA output is required, cut the jumper wire located next to the modulation output. 11 12 11 12 1 Mod V (dc) – + Mod V(dc) C + -- The modulating outputs replace any mechanical operator such as a T991. Observe polarity when connecting the control to the boiler.
Test The Power Supply Make sure exposed wires and bare terminals are not in contact with other wires or grounded surfaces. Turn on the power and measure the voltage between the Power L and Power N terminals (5 and 6) using an AC voltmeter, the reading should be between 103.5 and 126.5 V (ac). 5 6 V 103.5 to 126.5 V (ac) Power N L Test the Powered Inputs 1 2 20 to 260 V (ac) Boil Com Dem Dem Boiler Demand If a boiler demand is used, measure the voltage between the Boil Demand terminals (1 and 2).
CONNECTING THE CONTROL Make sure all power to the devices and terminal blocks is off, and remove any remaining jumpers from the terminals. 7 8 4 5Power6 DHW Prim P1 Reconnect the terminal blocks to the control by carefully aligning them with their respective headers on the control, and then pushing the terminal blocks into the headers. The terminal blocks should snap firmly into place.
Display Se c In tion s Ad talle va r nc ed View Menu (1 of 1) Description Outdoor Current outdoor air temperature as measured by the outdoor sensor. Room Current room air temperature as measured by the indoor sensor. This item is only available when an indoor sensor is connected to the control. B3 © 2010 D 270 - 08/10 Range -76 to 149°F (-60 to 65°C) 23 to 113°F (-5 to 45°C) Boiler Supply Current boiler supply water temperature as measured by the boiler supply sensor.
Display Se c In tio st n Ad alle va r nc ed Adjust Menu (1 of 2) Description Range Room Occupied The desired room air temperature during the occupied period. 35 to 100°F (2 to 38°C) Default = 70°F (21°C) D1 Room Unoccupied The desired room air temperature during the unoccupied period. 35 to 100°F (2 to 38°C, OFF) Default = 65°F (18°C) D1 Outdoor Design The design outdoor air temperature used in the heat loss calculations for the heating system.
Display Se c In tio st n Ad alle va r nc e d Adjust Menu (2 of 2) Range B3 Boiler Modulation Selects either a 2 to 10 V (dc) or a 0 to 10 V (dc) output signal. 2:10, 0:10 Default = 0:10 B3 Minimum Modulation The minimum percent modulation of the burner. 0 to 50% Default = 0% B3 Maximum Modulation The maximum percent modulation of the burner. 50 to 100% Default = 100% DHW Mode Selects the DHW mode of operation.
Testing the Control The control has a built-in test routine that is used to test the main control functions. The control continually monitors the sensors and displays an error message whenever a fault is found. See the following pages for a list of the control’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. TEST SEQUENCE Each step in the test sequence lasts 10 seconds.
MAX HEAT The control has a function called Max Heat. In this mode, the control turns on and operates the system up to the maximum set temperatures as long as there is a demand for heat. The control continues to operate in this mode for up to 24 hours or until the Item, Menu or Test button is pressed. This mode may be used for running all circulators during system start-up in order to purge air from the piping. To enable the Max Heat feature, use the following procedure.
Error Messages (1 of 1) E01 The control was unable to read a piece of information stored in its memory. Because of this, the control was required to reload the factory settings into all of the items in the ADJUST menu. The control will stop operation until all of the items in the ADJUST menu of the control have been checked by the user or installer. Note: The Advanced / Installer DIP switch must be set to Advanced in order to clear the error.
Technical Data Boiler Control 270 One Modulating Boiler & DHW Optional devices — — — — — — — — — — — D 270, A 270, D 001, D 070. Microprocessor PID control; This is not a safety (limit) control. 3.3 lb. (1500 g), Enclosure A, blue modified 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, meets ICES & FCC regulations for EMI/RFI. Indoor use only, 32 to 104°F (0 to 40°C), < 90% RH non-condensing.
