zoning with circulators

PDB2

I'm replacing my old boiler with a Wiel-McClain CGa-3, spark ignition

model. The boiler came with a Taco 007-f5 circulator. I bought an

additional pump, same model, thinking I would control my two baseboard

loops with the pumps same as my old set up. Now I see that the new

boiler control board has only one thermostat input and one circulator

output. Can someone walk me though how to wire the thermostats and some

external relays to power the pumps and keep it integrated with the

control board.

I've attached pdf of control board.....or at least I tried to.

Greg Maxwell

Zoning

You can use a multiple zone circ relay such as a Taco SR502 and use the end switch off that control tied into the input on the control board you have.

Jean-David Beyer

My W-M Ultra-3 can control up to 3 circulators.

(I am not a contractor.) I use Taco 007-IFC circulators for zoning too, but if I had this to do over, I think I would use a delta-P ECM circulator and zone valves. If you do not use the IFC models, you will almost certainly want flow-check valves in there.



The contractor I had for my sysem seems to use Taco 007s for everything. They certainly did not calculate the flow rate through the various parts of my sistem. My old system had a single circulator, my present one has four. My original system had 1 zone. My new one has two heating zones, a zone for indirect hot water heater, and an additional circulator because the near-boiler piping is now primary-secondary. That really needs calculating. One of my zones is surely overpumped, and the other one may be. The indirect and the primary loop are pumped exactly as the boiler manufacturer specified.

Mac_R

Something Easy and better

I would forgo the zone panels and fixed speed 007.  I really like the Delta T 007 from Taco.  this little pump is amazing.  You set it for a 20 degree difference between the supply and return piping and it will speed up and slow down to keep that difference.  It will only put into the living space what the living space needs.  It is really handy if you are using outdoor reset.  Remember our GPM requirements are dependent on BTU requirements.  GPM= BTU load/ (Delta T* 500)

That formula alone proves that we need a variable speed pump.  The nice thing about the 007 Delta T is it has end switches you can use for zoning.  I have taken the liberty of drawing up a wiring diagram for you.  They are a little more money than the fixed speed 007.  But they will save you money in the long run and make your home much more comfortable. 

Mac_R

Lets try that again

Does not look like the file posted.