Oil fired boiler need help with

gustavus

I have installed a hydronic heat exchanger in my existing electric forced air furnace plenium which will be heated via an oil fired boiler. Where I'm running into trouble is how to energize the fan from the electric furnace when the boiler is called for heat in this zone.

I also have a liquid to liquid heat exchange for the outside shop , this zone is using two grundfoss circulation pumps, how do I wire these to come on simultaneously when heat is called for. I have been told to run the shop side pump contiously, but would rather not.

What are my options using the Taco SR504 zone relay.

hoistdoctor

Without knowing what kind of system you have, I would run the two pumps for the shop parallel and switched by a zone relay controlled by a thermostat. As for the electric furnace, disconnect the elements from the sequencer and leave the fan on the first sequencer switch. Let the zone relay switch 24 volts to the sequencer.

beenthere

Tie both of the grundfos circs to the same circ terminals of the 504.

Install a fan liimt in the plenum above the hydro coil to turn on the fan when the air temp gets to X degrees, and shut the fan off when it drops to X degrees.

gustavus

Thanks Beenthere installing the fan/limit switch in the plenium makes the most sense to me.

As I want to use separate thermostats from each furnace for this zone. Leaving the electric furnace as a standby.

Next year I will install pex under the main floor with radiant basboards upstairs.

I'm using a Coloumbia KWO oil fired boiler with a tankless hot water supply, purchased the Taco SR504 now using only two zones.

The aquastats and low water senrty really confuse me and will have questions later to ask on these.

Thanks for the great forum.

beenthere

Tankless coils on boilers are very wastefull. Standby loss is too high.
An indirect is more efficient. Cost more up front though.
In many areas, an electric water heater cost less to use.