Floor heat recirculation pump wiring help

[broncoboy]

Greetings all. This is my first post.

Using NR-240A for radiant floor heat (yes, I know it's not approved for this function) in conjunction with a large electric water tank for storage.

The issue is when I lose power and the generator kicks on, the electric water tank is not powered as it was excluded from the system due to the high power consumption. This is problematic because my NR-240A needs the thermostat in the electric water tank to energize the external circulation pump which triggers the NR-240A to operate.

So, in theory, I could use my floor heating system with only the tankless while on the generator even if the electric tank is not operating IF I could find a way to get the recirc pump to operate when the tank is inop but also have it operate normally while it is in the normal powered configuration

Does anyone have any creative wiring configurations that could accomplish this?

The Navien has an internal pump as well, but it's not currently configured for use.
Bradford White (M250S6DS-1NCWW) has 2 heaters + 2 thermostats.

Thanks!

 

[broncoboy]

Well, okay then...

Found the lower thermostat was not being used to power the lower element so just being used as a switch. I rewired it so the power source was other than from the WH and now my pump works without the WH being powered but still has the WH thermostat controlling it.

Cheers