Rinnai RL75I recirculation problem

[Willy101]

Just installed a RL75I with a dedicated return line. Using a Grungfos Alpha2 15-55 pump. Hooked it up to the recirculation controller in the Rl75i and it works just as the documents says it should. Problem is that when the heater shuts the pump off, there is still 12V on the circuit. It keeps the pump's lights flashing and it probably isn't doing the pump any good. Rinnai didn't offer any help and local installers weren't any help either. Has any one run across this problem????

 

[Fitter30]

Diagram shows a relay could have a scr instead, Transient voltage with a digital meter. Have a old analog that has a little load probably 0 volts.

 

[Sponsor]

 

[Willy101]

Diagram shows a relay could have a scr instead, Transient voltage with a digital meter. Have a old analog that has a little load probably 0 volts.

Used both types of meters. Definitely 12V on circuit at all times, even with dip switch 4 on switch 2 turned off.

 

[Fitter30]

It's a triac instead of a scr which could produce voltage with wires not connected. Pumps electronics might be causing this problem. Might try adding a 120vac relay let heater pull in relay, 120 vac from incoming power run pump through relay contacts.
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