'/%3E%3C/svg%3E)
 --%3E %3Csvg version='1.1' id='Fill' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' x='0px' y='0px' viewBox='0 0 100 100' enable-background='new 0 0 100 100' xml:space='preserve'%3E %3Cpath fill='%23F15C02' d='M79.44,0.95H20.56C9.78,0.95,0.95,9.78,0.95,20.56v58.87c0,10.79,8.82,19.61,19.61,19.61h58.87 c10.79,0,19.61-8.83,19.61-19.61V20.56C99.05,9.78,90.22,0.95,79.44,0.95z M65.38,58.24l9.38,29.58L49.69,69.78L24.5,87.82 l9.34-29.6L8.8,39.6l30.73-0.17c0,0,6.98-19.61,10-28.93c0.54,1.36,9.88,29.1,9.88,29.1H91.2L65.38,58.24z'/%3E %3C/svg%3E){kind=small}
 --%3E %3Csvg version='1.1' id='Half' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' x='0px' y='0px' viewBox='0 0 100 100' enable-background='new 0 0 100 100' xml:space='preserve'%3E %3Cg%3E %3Cpath fill='%23F15C02' d='M30.05,70.23l3.79-12.01L8.8,39.6l30.73-0.17c0,0,6.98-19.61,10-28.93c0.54,1.36,9.88,29.1,9.88,29.1h1.58 L93.71,7.18c-3.58-3.82-8.66-6.23-14.28-6.23H20.56C9.78,0.95,0.95,9.78,0.95,20.56v58.87c0,5.41,2.22,10.32,5.79,13.88 L30.05,70.23z'/%3E %3C/g%3E %3Cpath fill='%23FBC8B4' d='M93.71,7.18L60.98,39.6H91.2L65.38,58.24l9.38,29.58L49.69,69.78L24.5,87.82l5.55-17.59L6.75,93.32 c3.55,3.54,8.44,5.73,13.82,5.73h58.87c10.79,0,19.61-8.83,19.61-19.61V20.56C99.05,15.4,97.01,10.69,93.71,7.18z'/%3E %3C/svg%3E){kind=small}
MANUALS (4)
Product Highlights
Description
Specs
| Application: | Single Boiler |
|---|---|
| Stages: | 1 Boiler |
| Width: | 2-7/8" |
| Height: | 4-3/4" |
| User Interface: | LCD Push Button |
| Voltage: | 24V |
| Depth (Inches): | 7/8" |
| Ambient Conditions: | Indoor Only: 32°-104°F < 90% RH non-condensing |
| Power Supply: | Class 2 24 V (ac) |
| Relays: | 240 V (ac) 5 A-1/6 hp |
| Max Temp (F): | 266°F |
| Min Temp (F): | -60°F |
| Temperature Range (F): | -60°F - 266°F |
| Control: | Microprocessor PID control |
| Weight (lbs): | 1.3 lbs |
| Demands: | 24 V (ac) 2 VA |
| Sensors: | NTC Thermistor, 10 k ohm @ 77°F |
Questions?
You May Also Need
Product Reviews
Most Liked Positive Review
excellant boiler control
Most Liked Negative Review
 --%3E %3Csvg version='1.1' id='With-RB' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' x='0px' y='0px' viewBox='0 0 100 100' enable-background='new 0 0 100 100' xml:space='preserve'%3E %3Cpath fill='%23FBC8B4' d='M79.44,0.95H20.56C9.78,0.95,0.95,9.78,0.95,20.56v58.87c0,10.79,8.82,19.61,19.61,19.61h58.87 c10.79,0,19.61-8.83,19.61-19.61V20.56C99.05,9.78,90.22,0.95,79.44,0.95z M65.38,58.24l9.38,29.58L49.69,69.78L24.5,87.82 l9.34-29.6L8.8,39.6l30.73-0.17c0,0,6.98-19.61,10-28.93c0.54,1.36,9.88,29.1,9.88,29.1H91.2L65.38,58.24z'/%3E %3C/svg%3E){kind=small}
not very good
I would buy agaun
I would buy it again because I have.
Great product Great Service A+++
yes
Worked better than expected
Functions fine, needs design change
Wrong product for my application
i installed this product on two separate boilers
Good price. Good product.
Works great
Product Q&A
21 QuestionsQ: Will this unit work with a Honeywell L8124A aquastat and Taco SR506 relay. I also have DHW through the tankless coil with John wood booster tank. Thanks!
Asked by Eyball 7 years ago
Add your answer
Verified Reply- Supplyhouse.com TeamThese items can be used in conjunction with one another depending on proper setup. Supply house has no installers on staff to advise on installation process or compatibility within your specific system, but you can reach out to the manufacturer directly to confirm at 1-250-545-7749.
Q: Is this compatible with an aquastat l8148e 1265?
Asked by Eric 10 years ago
Add your answer
Verified Reply- SupplyHouse StaffThe 256 boiler relay would wire to the Aquastat TT. There would be no issues connecting to this Aquastat.
Q: Can this control be used with a Grundfos Alpha pump, in a single zone gas-fired 30-year-old American Standard GPH 135 boiler system?
Asked by Steve 12 years ago
Add your answer
It will work with any single stage boiler as long as the the main gas valve is powered by low voltage. .if it high voltage it can be tricky to wire
Yes, this control would work fine to reset boiler water temperature with outside air
The circulator you have chosen is a variable speed one that will vary water flow depending on pressure changes. The Tekmar control only varies the water temperature being produced by the boiler depending on the outdoor temperature. The circulator and the Tekmar control don't technically interact with each other. In case you don't know..... make sure you put the min temperature on the Tekmar control at 135 or 140. If you let the boiler run below that you will get all kinds of internal flueway condensation. that condensation is acidic and not good for the boiler or burners.
I use the control on an oil fired boiler system so I think it would work on any hot water system. It saves energy but heating the circulating water to a temperature based on the outside temperature. As the outside temperature increases the water is heated to a lower temperature that the maximum 180 thus saving energy. The heating curve can be adjusted but that was beyond my electronic capability. Mike
Yes, I have both in service at my own house. Make sure to set Tekmar 256 minimum supply temperature properly to avoid flue gas condensation, which leads to cast iron section face rusting and unlined chimney destruction. For ex., no less than 140dF on most applications for cast iron. System supply sensor location is also quite critical. I initially tried surface mount on steel nipple out of boiler with insulation over it, then installed a well in a tee before zone branches. Directions seem that they could be clearer. Use good judgment for other settings.
Not sure what you are trying to accomplish with controlling just the pump but we used this control in a high school on a 50 year old oil fired tube boiler and it works great. We keep our circulator running 24 7 and we use the optional timer to have control for day night settings. The controller is very flexible and offers a number of curves/settings. This controller replaced the original pneumatic control system. If using to control a pump you may need a relay. I hope that helps. Mike
If the water temperature is controlled electronically--thermostat--this is exactly the job this reset control is designed to do. The instructions and diagrams are complete and clear. The action is to increase water temperature as outdoor temperature falls. You'll love it!
Q: Have a Burnham PVG5ni-GS with DHW priority. Plan to add an Outdoor Reset. Is the Tekmar 256 Outdoor Reset a good compatible choice ?
Asked by spyros 14 years ago
Add your answer
Yes, 256 is a good option, you can add a 033 timer to add night setback Sent from my iPhone
You can definitely use the Tekmar 256 with that boiler. You also need to add a system bypass to protect the boiler against condensation from the lower water temperatures (140F). If you can't install a bypass, you will need to keep the boiler temperature at a minimum of 160F, which will not give the full benefits of the Outdoor Reset Control. Joe Starosielec ecuacool.com
The 256 is a great control for doing outdoor reset. I install a lot of them on existing boilers. Here's where you have to potentially work around a problem. You say you have DHW priority. I'm assuming you have an indirect water heater connected to the boiler. Depending on how you are doing that you may have to do some sort of isolation relay to tell the boiler not to pay attention to the 256 when the domestic hot water calls. That way the boiler will ramp up to full temperature upon a call for the domestic and not turn on to a lower outdoor reset temperature. It's actually fairly simple and if need be I can talk you through that. Any questions just let me know. Jeff
Q: Is this capable of post purging circulators for a while after the thermostat ends it's call for heat? If not, is there something that will do that in conjunction with this device?
Asked by learning 14 years ago
Add your answer
If you use a Tekmar 260 control this would have a 20 second post purge feature on the pump. The 265 has no wiring for a pump. You could put a delay off timer in the pump circuit for the boiler if you use the 265 control.
Call the mfg of the circulator that you are using never heard of a post purging circulators before
I am using the Tekmar #256 for outdoor reset, in conjunction with a Honeywell #8124 Triple Aquastat, with the thermostat as the control of when the circulator, and the boiler, run. Ifis not nothing runs. I still get some short cycling due to imperfect coordination between ermostat and the aquastat (Tekmar). I do not find that the Tekmar control provides circulator run on when the thermostat is not calling for heat. Don't know if it can be set up to do that. Try downloading the manual from the Tekmar website: http://tekmarcontrols.com/hvacsystems/256.html. You may find the answer there. Good luck.
I'm not sure what is meant by "post purging circulators". Having said that, this unit only serves to turn on and off the boiler fire based on a temperature curve that relates the boiler temperature with the outside air temperature. Thermostatic control of individual zone circulators is unaffected. Hope this helps. Howard Levy
No, the Tekmar 256 will not do this. I installed one about 2 years ago and am very pleased with it's performance. It has worked flawlessly so far. With my installation I did have to install an additional RIB(relay in a box). As far as I know there is no "out of the box" component to accomplish "post purging". It probably does not pay to pursue trying to accomplish this since the 256 adjusts the boiler temp. For example, if the outdoor temp was 45 degrees the 256 may adjust the boiler temp to 140 degrees. To run the circulator for a set amount of time at lower temps may be just a waste of electric. You would be better off installing an automatic vent damper if you don't already have one. This will prevent the heat of the boiler from going up the flue during standby. I would leave this to the pros though as it could be dangerous if installed improperly.
Q: Will the 256 work with a Weil McLain GV4 boiler? Would an extra relay be needed?
Asked by 14 years ago
Add your answer
Verified Reply- PexSupply StaffYes, the 256 control will work with a Weil-McLain GV-4 boiler. You will not need an extra relay.
Yes, this control will work with your boiler.
Q: I have a zoned system with fin tubes in the basement, and cast iron radiators in the rest of the house. Can a single Tekmar 256 be used in this setup, and if so, which "terminal unit" should be selected in the configuration?
Asked by Eric 15 years ago
Add your answer
Verified Reply- PexSupply StaffYes you can use this control for your setup. We would recommend using the Fin–tube Convector (4) setting.
Q: will this control work with Utica MGB piped as primary/secondary? when the boiler is reset by controller, will the vent damper close until it's ready to fire again?
Asked by rhubarb42 15 years ago
Add your answer
Verified Reply- PexSupply StaffThe Tekmar 256 Boiler Control is a control designed to regulate the supply water temperature from a single boiler based on the outdoor temperature. This control will not operate a vent damper.
Q: I have gas-fired boiler Smith model GBX with standing pilot. I cannot find boiler demand switch on wiring and connection diagram. What are points of connection Tekmar 260 to my boiler control? Thank you
Asked by Mike 15 years ago
Add your answer
Verified Reply- PexSupply StaffContacts 5 and 6 on the Tekmar 256 control are for the boiler.
Q: Will this work with my setup. Single boiler has two zones/circulators (Taco 503 controller) one of the two zones is a 40 gal water tank that is fed from the boiler, does not have its own heat source.
Asked by JJ 15 years ago
Add your answer
Verified Reply- PexSupply StaffNo, you will need to use the Tekmar 260 control in this situation.