Primary Secondary Zoned with Circulators

[groch]

I would like to install a TARM SP30 in a primary loop configuration. The current install is HW BB zoned with 4 Circulators, 3 Heat, 1 DHW controlled with an ARGO ARM842. My question is what control is needed to operate the Oil Boiler Circ, when one or more of the zones is active. My first thought was connect the boiler Circ. to the Burner control, but the burner cycles. The TARM boiler Circ operates anytime the its above a threshold temp, 140?

I have attached my layout for public comment.
Thanks

 

[Nofossil]

I'll let the primary/secondary circulator zone guys take a crack at this, but I'd expect that each boiler circ would operate based on the associated boiler temp via aquastat or some such.

 

[BrownianHeatingTech]

Your current control should have what's called an "end switch." That's what tells the boiler to heat up because there is a zone calling.

What you essentially need to do is to take that signal and direct it to one boiler (and circulator) or the other. You use an aquastat on the wood boiler to do that. If the wood boiler is warm, then it sends the signal to the wood boiler's circulator. If the wood boiler is too cold, then the signal goes to the oil boiler, just like it currently does.

Depending on your setup, you may need to add a relay of some sort to isolate the 110V circulator power, if the end switch operation is currently based on 24V.

Joe

 

[groch]

Thanks. I will investigate the current control system further to see what signals and states are available during the heat cycle.