Service Bulletin

SB 046

Oct 17, 2008
Connection to Viessmann Vitodens 100
Compatibility: The Viessmann Vitodens 100 modulating condensing boiler is compatible with the following tekmar controls: ! ! ! tN4 Boiler Reset Module 420 tN4 Universal Reset Module 422 tN4 Universal Reset Module 423
In order to connect to a tekmar control, a Viessmann OpenTherm Module (Part Number: 7249069) is required. Sequential staging of multiple boilers using a tekmar control is not possible at this time. For multiple boiler applications contact Viessmann. Piping: It is recommended to follow the near boiler piping directions provided by Viessmann using a low loss header or the use of primary-secondary piping. The Vitodens 100 will operate the boiler pump, while the tekmar control operates the DHW pump and any system pumps and zone pumps. Piping using Low Loss Header Piping using Primary-Secondary
File and version v0011-May0803-L

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Wiring Instructions: Follow the wiring instructions included with the Viessmann OpenTherm Module. Wire the tekmar control to the OpenTherm Module as follows:
Essential tekmar Control Settings: The tekmar 420, 422, and 423 include switch settings located on the left side of the module. Ensure the switch labeled Off / tekmar Stager is set to the tekmar Stager position (right). 420 Switch Settings 422 Switch Settings 423 Switch Settings

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Target Temperature Differences: The tekmar voltage to target temperature curve is different than that of the Viessmann OpenTherm Module. The table below is a comparison. Voltage V (dc) 2 2.10 tekmar Boiler Target --- (OFF) 50F (10C) 68F (20C) 72F (22C) 86F (30C) 103F (39C) 121F (49C) 139F (59C) 157F (69C) 174F (79C) 192F (89C) 210F (99C) Viessmann OpenTherm Target 49F (6C) 49F (6C) 49F (6C) 81F (27C) 91F (33C) 104F (40C) 115F (46C) 127F (53C) 140F (60C) 151F (66C) 163F (73C) 176F (80C) Viessmann Boiler Differential Cut-out 57F (14C) 57F (14C) 57F (14C) 95F (35C) 106F (41C) 118F (48C) 129F (54C) 142F (61C) 154F (68C) 165F (74C) 178F (81C) 190F (88C) Viessmann Boiler Differential Cut-in 32F (0C) 32F (0C) 32F (0C) 70F (21C) 81F (27C) 93F (34C) 104F (40C) 117F (47C) 129F (54C) 140F (60C) 153F (67C) 165F (74C)

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tekmar Control Settings Due to the temperature differences between the tekmar target temperature and the Viessmann OpenTherm target temperature conversion, it is recommended to design the heating system using the Viessmann operating temperature and then use the chart to back-convert to the tekmar temperature. Example 1: If the heating system design water temperature is 176F (80C), then using the chart it is found that the required tekmar temperature is 210F (99C). The DHW indirect coil operates at 176F (80C). In this example: ! Boiler Design should be set to 210F (99C) ! DHW Exchange should be set to 210F (99C) ! Boiler Maximum should be set to 210F (99C) Example 2: If the heating system design water temperature is 130F (54C), then using the chart it is found that the required tekmar temperature is 140F (60C). The DHW indirect coil operates at 176F (80C). In this example: ! Boiler Design should be set to 140F (60C) ! DHW Exchange should be set to 210F (99C) ! Boiler Maximum should be set to 210F (99C) Since the Vitodens 100 is a condensing boiler, it is recommended to set the Boiler Minimum to OFF, which allows the boiler to operate at the highest efficiency. Due to the differences in temperature targets, if the heating system is required to maintain a specific minimum or maximum operating temperature, a mixing device (3-way valve or variable speed injection) operated by the tekmar control is required.

Sincerely yours,

Jay Vath tekmar Control Systems Ltd.

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Gas-fired wall-mounted condensing boiler Standard heating boiler 25 to 230 MBH Combi heating boiler 25 to 91 MBH Multi-boiler installation 344 to 920 MBH

VITODENS 200

Innovative. Highest efficiency. Reliable.
Maximize fuel efficiency and minimize your annual heating cost! This high-tech wall-mounted condensing boiler is economical, extremely reliable and compact and its unparalleled in the heating industry. Here is why The benefits at a glance: Highest efficiency of up to 98% with full modulation and 95.2% A.F.U.E. on all models. Maximum reliability High-alloy stainless steel (SATi) Inox-Radial heat exchanger constructed in compliance with CSA B51 and ASME Section IV. Meets ASME/CSD-1 requirements (for WB2 11-44/15-60). Protect the environment Extremely low emissions with modulating MatriX-compact gas burner. NOx: 8.9 ppm (air-free) CO: 5.5 ppm (air-free) Compact, lightweight design. Zero clearance to combustibles. Limited space is not an issue. Clean, esthetically pleasing appearance for installation anywhere in your living area. Extremely quiet operation; quieter than most refrigerators. Smart burner technology Factory calibrated, self-adjusting burner. No adjusting in the field, reduced operating cost. Powerful and user-friendly outdoor reset control, built-in and prewired with diagnostic system. Controls multi-temperature space heating and DHW systems. Reliable DHW production two ways: Combi model features an integrated DHW Quick System. No DHW tank required. Unlimited DHW supply with a stand-alone DHW tank with any other Vitodens 200. Multiple venting options Horizontal or vertical sealed combustion coaxial vent system (factory supplied). VITODENS 200
Rated input range (NG) Rated input range (LP) Depth Width Height WB2 MBH MBH inches inches inches 6-24C 25-91 25-19 35
Viessmann Manufacturing Company Inc. 750 McMurray Road Waterloo, ON N2V 2G5 Canada Tel.: (519) 885-6300 Fax: (519) 885-0887 www.viessmann.ca Viessmann Manufacturing Company (U.S.) Inc. 45 Access Road Warwick, RI 02886 U.S.A. Tel.: (401) 732-0667 Fax: (401) 732-0590 www.viessmann-us.com
Inox-Radial heat exchanger surface
MatriX-compact gas burner
Powerful and user-friendly control
Horizontal, vertical or hybrid sealed combustion double-pipe vent system (field supplied). Horizontal or vertical single-wall vent system (field supplied). Multi-boiler installation Models WB2-44 and -60 can be combined to a maximum of 4. Ideal for light commercial applications. One version for all elevation levels (000 ft. / m). Fast, simple conversions to natural or propane gas.
6-24 25-91 25-8-32 37-124 37-11-44 55-172 55-15-60 80-230 80-23 35
Supply / Return 75C / 60C 167F / 140F

Partial Load in %

Technical information subject to change without notice.

04/08 Printed in Canada

Vitodens 200 Boiler Efficiency
Supply / Return 40C / 30C 104F / 86F Supply / Return 60C / 48.8C 140F / 120F
Combustion Efficiency in %