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Laars Magnatherm boiler pumps

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aircooled81
aircooled81 Member Posts: 205
I am curious if I misunderstood the Seq of Op in the IOM, or if something is strange on the parameters.
Should the primary pump on the idle boiler be off when this boiler is not being used in Master Slave Config?
I have a pair of Magnatherms that are cofigured for Master Slave, but when a boiler is not in use, but other boiler is firing, the boiler not in use has a primary pump still being commanded on..
Checked the min dealy time before pump turns off after firing, thats not the problem. DHW is not enabled. Boiler is remotely commanded. I removed power to the protonode, bms bacnet, to confirm its not being commanded so externally, from others.
I have power from the terminal on the honeywell control that is actually calling for this pump, so I can rule out VFD is in local or hand control. But why would it run when only the other boiler is being called for?

This is an issue because we are sending return water directly into the supply side, and I think this has done something to the sequence because now boiler 2 seems to run all day, not meet setpoint but boiler 1 does not stay enabled very much or long when in use. There is an ocassional ‘add 2’ note that appears, and ‘limit’ or something to that sort, but boiler 1 will never really fully come on line for too long.