Rinnai w booster tank? NO HW

Krawdad

Krawdad

I am only able to get this customer hot water when I open the bypass on the hot water out piping from Rinnai. Stainless Taco Pump very hot to touch so thinking either pump gone or flow switch. The pump does pump into the cold side. 

Larry Weingarten

Hi, Is there any provision in place for flushing air from the pump, using water pressure? The pump is most likely either air locked or damaged. Flushing out air would be my first action. Alternately, something else in the system may be blocking flow...

Yours, Larry

Krawdad

Thank you Larry! Be back there this morning. 

SteveSan

What is the model number of the Taco pump? You can take an amp reading off the motor, if working as it should it would be at nameplate amps. As for running hot to the touch, normal temp should be between 140-160 degrees.

Try purging the air and if you have any question, please give Taco Technical Services a call during normal business hours Mon-Fri 8am-5pm EST 401-942-8000

Mad Dog_2

You DO know that flow switch has a minimum draw to activate .. I found out the hard way. The HO had an open trough Kohler Lavatory faucet..you know the type...cascading waterfall spout.  No aerator.  Even on full open the Rinnai would NOT fire up...Cold water out of the hot.  MAD DOG 🐕 

Krawdad

Ended up the customer played with a " bypass " valve and i learned to never assume any valves default position. The piping was kind of funky too. will try and post a follow up sketch to show what piping should look like to a storage tank.