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Plumbing and Wiring a Superstor ss-40 into an existing system to replace a tankless coil

I just picked up a used 2 y/o SuperStor ss-40 to replace the tankless coil on a Burnham RS-111. Can I modify the Honeywell L8124 A,C,J aquastat to just control the boiler or do I need to buy a new controller?  Can someone confirm this to be correct and tell me how to rewire?

I also need to understand how to wire ss-40 Honeywell R845A thermostat so that it will have priority over heating zones.  Currently, the boiler uses one circulator for the 3 heat zones.  If anyone can assist me I would be very grateful.  I have have experience in AC wiring, and have replaced 2 60 y/o boilers with newer Weil-Mclains Gold series in my rental house.  Just to make sure I did it right I hired a boiler technician to "tune" each installation.  They are running at 87%, and 89% efficiency.


  • lchmb
    lchmb Member Posts: 2,997
    edited October 2011

    A weil mclain gold at 89% scares me (is this oil?)....reference wiring, do yourself a favor and pick up a taco sr504. Makes life easier, put's everything in one package and easier to troubleshoot down the road. As far as the aquastat, I would simply turn the low limit to 140. The boiler has run it's entire life hot and it may cause issue's to make it go cold now.

    Just noticed you have zone valve's sorry.. Use a sr503, have the end switch call on your circ for your 3 heat zones. Use the indirects aquastat to call on the circ for the indirect and put it on the priority zone.

  • billtwocase
    billtwocase Member Posts: 2,385
    I agree

    You could probably go as low as 120, but I wouldn't cold start that boiler. I would suggest installing one of the 89% Golds. RS Burnhams are lousy for recovery, and best will be around 83-84% efficiency, if not less on that model. Stack temp kills them, as most heat goes up and out. I would go Honeywell Z/V for the indirect. What valves are used for the heat? You probably have a 40 VA transformer now, and will power an additional motorized Z/V only, otherwise you will need a 50 VA if you have Taco and use another one.
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