Wiring Taco SR-504

[dave42]

I have a Taco SR-504 electronic control. Our system is set up with an expansion tank that is piped directly to the boiler and has a 0010 pump that supplies the boiler with water from the tank (primary loop)This primary zone trips the boiler via a connection to the T-T circuit on the boiler.

We then have a supply manifold that comes off the expansion tank and 4 007 pumps come off the manifold and supply heat to our 4 different zones.

The SR-504 is wired so that when any one zone (007) calls for heat, the 0010 pump circulates water through the primary loop. That is a necessity as the supply and return manifolds take off from the same pipe in the primary loop, and if the 0010 pump does not circulate water through the primary loop, we can't get heated water into the supply manifold.

 

However, currently, each separate zone (007) can also cause the boiler to turn on through the SR-504. Thsi seems to be creating overlapping demand situations on the boiler.

I am trying to make a setup where the only thing that will turn on the boiler via the T-T connection is the aquastat on the expansion tank.

I would like to set up the system so that if any thermostat in the house calls for heat, its corresponding 007 pump as well as the 0010 primary pump will turn on.

But only when the temp of the expansion tank drops below the setting on its aquastat, will the boiler fire.

Is it possible to wire the SR-504 like this, or do I need a different electronic control?

Thank you.