Wiring Aquastat and Switch Relay ZC and ZR?

Hello,

Near the last few steps in setting up the DF-520, and have come across wiring diagram on the TACO SR506 switching relay which conflicts with the diagram descriptions on how to wire the relay to the Honeywell L8124A Aquastat.

Does the ZC on the Aquastat go to the ZC on the SR506 switching relay?

The diagram below (June 1, 2006) from the SR506 Instruction Sheet states ZC (Aquastat) goes to the End X terminal (Switching Relay), and the ZR goes to the ZC terminal, but the description states the ZC (Aquastat) goes to ZC (switching relay), and ZR(Aquastat) goes to the End X terminal on the switching relay:

The older ZR506 Instruction Sheet (Oct 15, 2005) has a wiring diagram that matches the description.

I'll post a picture of the wiring diagram with the L6006A, Burner, and SR506 later tonight.

Thanks,

Dave

Here is the wiring diagram with the SR506 and Aquastat. Does the SR506 and L6006A look correct?

The photo has to be resized. It's too big. The wiring on the first two schematics is correct.

Stoker-man,

I will repost the wiring diagram with smaller size. So which one is correct?

1) First Taco SR506 diagram (June 1, 2006) shows the following:
ZC (SR506) goes to ZR (Aquastat)
X End (SR506) goes to ZC(Aquastat)

2) Second Taco SR506 diagram (Oct 15, 2006) shows the following:
ZC (SR506) goes to ZC(Aquastat)
X End (SR506) goes to ZR(Aquastat)

I believe #2 above is correct rather than #1. Do you agree #2 is correct?

Thanks,

Dave

The wiring diagrams are both correct. It depends upon which style of relay you are using. Apparently they look different.

Stoker-man,

The diagram for the SR506 Switching Relay 102-165 dated June 1, 2006 shows:

ZC (SR506) goes to ZR (Aquastat)
X End (SR506) goes to ZC(Aquastat)

But the text under the digram in the "Jumper Placement" states the reverse connection:
"Connect terminal ZC to ZC terminal on the aquastat
control. Connect the other end switch X to ZR terminal on the
aquastat control."

I agree the new and old relays could be different, but the diagram and text don't match for the same switching relay creating the confusion.

Thanks!

I was able to speak to a tech support person from Taco, and he mentioned to wire it according to the diagram instead of the text. However, he thought it would work either way.

FYI. Thanks.

I received email from Taco support, and they provided a new instruction sheet for the switching relay with wiring matching the #2 description. I am attaching it to this post for anyone planning on using the SR504 or SR506.

Thanks!

Dave

I moved the L6006A on the diagram from a previous post in this thread since it was only turning off the timer, and not the stoker when the boiler dropped below the low temp setting during fire out. Here is the updated wiring diagram I decided to use requiring the L6006A bypass switch to be set to ON to start from cold while running oil or coal.