Tekmar 256 One Stage Boiler Control

This controller does exactly what it is intended to do. I am not an HVAC expert by any means, so it took me awhile to figure out what I needed to do (a couple of hours), but once that was accomplished, I ended up having a relatively easy time installing the controller. To do this you will need to be able to understand the boiler's wiring diagram in order to properly attach the controller to the boiler. You will also need to understand how to wire your water heater if it is also heated by the boiler. The setup of the controller itself is a little bit complex, but the instructions are written well enough to make the steps easy to follow. So far it has adjusted the boiler water cutoff temperature exactly as per the set points chosen during the setup procedure.

Took about 2 hours to install not being all that knowledgeable with hydronic furnaces. In my case, I installed it between the power supply for the burner circuit and wired it to the "call for heat" from the zone valves. The burner contacts are dry, meaning they don't give power, just a relay that is open or closed. I left the mechanical Honeywell high limit switch installed as a backup safety switch. This will increase or lower your boiler temp depending on the temp outside. Programming is fairly simple as well. Also a warm weather shutdown, meaning if its warm outside, even if there is a call for heat, the furnace will not fire. I only wish I knew this kind of product existed 10 years ago.

Saves you time & money. You can set it up to turn off the boiler at whatever temp you set. You can adjust boiler settings quickly & easily. Quick to install once you figure out how it all goes together. I have several of these things running w/o complaints.