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Tekmar 401 and Combi Boilers

BigMike Member Posts: 2
Hello everyone! This is my first post but I'm at a standstill designing a new heating system for an investment property my wife and I are to close on at the end of the month. I've been searching long and far across the web for some answers and most searches landed me here. If anyone can help me out I'm open to some options.

I would like to install a Combi boiler that would heat 3-4 zones of radiant through a buffer tank. The house only has 1 bath and I'm looking for a control system that can be accessed remotely to monitor/operate. My reason for wanting a Combi is that it's an economical option, and using a Locinvar Knight with an indirect DHW tank significantly tises the cost of the project.

I'm thinking of a Navien NCB 240 or an HTP EFT and I would like to control them by a Tekmar 401 house control and Gateway 485 remote access.

Can anyone tell me if the 401 will control the Navien or HTP?
Will a Gateway 485 work with a 314 or 316 if the 401 won't work?
Is there a list of compatible boilers with the 401 out there?
Any other good options out there?



  • Zman
    Zman Member Posts: 7,330
    For the 401 to work with all the bells and whistles, it needs to have control of the boiler modulation. On residential systems that is usually 0-10VDC. It looks like the HTP model is compatible and the Navien is not.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • BigMike
    BigMike Member Posts: 2
    ZMan thanks for pointing that out, that's exactly what I was misunderstanding. It looks like the HTP is the winner, thanks again!