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$220.50 each
In Stock
Order by today, receive Tuesday
MANUALS (4)
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Easy Returns No restocking fee for 90 days
Product Highlights
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1 Boiler
4-3/4"
24V
7/8" Depth
-60°F Min Temp
266°F Max Temp
Description
–
The Tekmar 256 Outdoor Reset Boiler Control is a microprocessor-based boiler control designed to regulate the supply water temperature from a single-stage boiler using the outdoor temperature. Avoid short cycling and temperature swings with Tekmar controls that continuously adjust the boiler differential. This boiler temperature reset control has LCD display and includes both a minimum boiler setting and a Warm Weather Shut Down option.
Specs
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| Application: | Single Boiler |
|---|---|
| Stages: | 1 Boiler |
| Width: | 2-7/8" |
| Height: | 4-3/4" |
| User Interface: | Push Button LCD |
| 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 |
| Min Temp (F): | -60°F |
| Max Temp (F): | 266°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?
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Call or text 888-757-4774
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Product Reviews
4.66 out of 41 reviews
95% would recommend this product
5 star
80%
4 star
15%
3 star
0%
2 star
0%
1 star
5%
Customer Images
Most Liked Positive Review
excellant boiler control
i bouight Tekmar 256 to replace my old Honeywell T475A 1032 outdoor reset controller. I made right choice. New Tekmar 256 woks better than my old honeywell. If you would like to control just your boiler On/off based on outdoor reset, All u need Tekmar 256. Very easy to install.
VS
Most Liked Negative Review
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not very good
Never worked right. Removed it and installed
honeywell outdoor reset that workes great
Showing 1-10 of 41 reviews
I would buy agaun
Great Service. Prompt.
Smoke
Illinois
9 months ago
Verified Buyer
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I would buy it again because I have.
I use this to control boilers for the greenhouse. It does a good job for what it is, I should have bought a 3 stage.
Steve
Quincy, Illinois
1 years ago
Verified Buyer
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Great product Great Service A+++
Super Fast Shippig
Norb
Ohio
2 years ago
Verified Buyer
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yes
These are reliable controls. I have used them over the years and have never had a failure.
gerard
madison wi.
3 years ago
Verified Buyer
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Worked better than expected
I added the boiler reset and a heat pump hot water heater. I now burn 30 to 40% less oil. The boiler only needs to run at 135° to 165° to heat the house. My only concern is that I have five zones and because the boiler doesn't get very hot it cycles a lot.
Dave
Massachusetts
3 years ago
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Functions fine, needs design change
We've used this model several times and each time I find myself wishing the designers would enlarge it to allow more room for the wire connections. I've never found a boiler room that required the reset control be no larger than a pack of cigarettes.
tim
Linton, IN
4 years ago
Verified Buyer
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Wrong product for my application
I purchased this product in error. I have a oil fired single stage hot water boiler with a domestic water coil. The Tekmar 256 can't handle the coil. The Tekmar 260 would work for my application but at more than 2 1/2 times the price, I could not justify it.
Supply House accepted the return very easily, so all is good.
Supply House will remain my go to for all my plumbing and HVAC needs.
Joe S
Glenmoore Pa
4 years ago
Verified Buyer
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i installed this product on two separate boilers
the customer saw the difference in gas usage from the previous year's Month and the currant and saw the savings. it paid for itself in one year.
energy saver
Western Massachusetts
4 years ago
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Good price. Good product.
See title.
Whoajaws
Ohio
5 years ago
Verified Buyer
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Works great
Easy to install easy to use
Hal
Mn
5 years ago
Verified Buyer
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Product Q&A
21 Questions21 Questions
Q: Will this device work with a ground-source heat-pump that's supplying a radiant system?
Asked by tlbranth 15 years ago
Add your answer
Verified Reply- PexSupply StaffAs far as we know, it will not. You may want to check with the heat pump manufacturer.
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Q: Is there any energy savings with this control, if so how much?
Asked by Dave 15 years ago
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Verified Reply- PexSupply StaffYou should save about 10%-15% with this control.
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Q: Will this controller work with my Weil McClain CGa boiler?
Asked by Green 15 years ago
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Verified Reply- PexSupply StaffYes, this control will work.
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Q: Will this control work with a Weil-McLain CGM-5 natural gas 2 zone system?
Asked by Tim the tinkerer 15 years ago
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Verified Reply- PexSupply StaffYes, it will.
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Q: I have an older (90's) Weil McLain HE-II gas hot water boiler, cast iron baseboard heat. 2 zones and 2 programmable thermostats. Is this the correct unit for me?
Asked by 15 years ago
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Verified Reply- PexSupply StaffYes, this control will work for your boiler.
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Q: Can this unit be used with my programmable thermostat or does it overide it?
Asked by Bob 15 years ago
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Verified Reply- PexSupply StaffThis control can be used with a programmable thermostat, but it would effectively override the thermostat under certain circumstances. You would need to adjust the boiler control if you wanted it to be hotter in your house than the boiler control would allow, for example.
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Q: Will the 256 work on a Weil-McLain GV-4 propane unit with 3 zones.
Asked by jed 16 years ago
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Verified Reply- PexSupply StaffYes, as long as one of the zones is not an indirect water heater.
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Q: I have an old oil hot water boiler with a tankless water heater & baseboard. Will this controller work with my boiler???
Asked by PJ 16 years ago
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Verified Reply- PexSupply StaffNo, this control will not work for you. You need the Tekmar 260 control (SKU: 260).
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Q: Will this work on a Burnham Series 2 Hot Water boiler with 4 zone valves?
Asked by 16 years ago
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Verified Reply- PexSupply StaffYes, it will work on this unit. However, if your boiler also has an indirect water heater, you will need the 260 boiler control instead.
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- Ian
Yes, but it will require some detailed wiring on your end and possibly a relay and transformer. Wiring diagrams for that application are available on the tekmar website. I've also heard that their customer service is pretty willing to point you in the right direction.
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Q: Can you tell me if this unit will work with a wood burning boiler? Right now I have a Honeywell Aquastat to control the boiler.
Asked by Michael 16 years ago
Add your answer
Verified Reply- PexSupply StaffNormally, outdoor reset controls do not work in conjunction with wood burning boilers. We recommend that you consult with the manufacturer of your boiler to see if it is compatible.
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