Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

Rheem RTE13 Tankless 240v water heater problem


audioi's Avatar
Member

Join Date: Mar 2012
Posts: 60
NY

01-28-18, 06:54 AM   #1 (permalink)  
Rheem RTE13 Tankless 240v water heater problem

Its a 1.5 year old heater that heats correctly but won't stop!

Works correctly until you turn the faucet off. The 2 system active red indicator lights remain on until the internal breaker opens, what should I look towards as the problem?

 
Sponsored Links
PJmax's Avatar
Group Moderator

Join Date: Oct 2012
Posts: 41,205
NJ

01-28-18, 10:50 AM   #2 (permalink)  
Looks like there is a spring loaded plunger (3) inside the cold water inlet that activates a magnetic switch (4). It needs to be checked for mineral buildup. It needs to slide easily to signify water flow to the heater.

Servicing information.... rheem/FetchDocument.aspx/RTE_series


~ Pete ~

 
audioi's Avatar
Member

Join Date: Mar 2012
Posts: 60
NY

01-28-18, 12:25 PM   #3 (permalink)  
I took that apart and it was clean.

 
PJmax's Avatar
Group Moderator

Join Date: Oct 2012
Posts: 41,205
NJ

01-28-18, 12:36 PM   #4 (permalink)  
But does it slide easily inside the housing. That's how the heater knows to turn on. The water flow draws that piece in.... in the direction of the flow. When the water flow stops.... the spring pushes the slide back out.


~ Pete ~

 
audioi's Avatar
Member

Join Date: Mar 2012
Posts: 60
NY

02-04-18, 05:33 AM   #5 (permalink)  
Yes, when I slide a metal screw driver in to where the plunger is, the plunger comes out with the screwdriver. I have noticed if I turn the heater on low and run it for about 20 seconds, it works fine and does not stay on active. If I heat the unit up by running water at a higher temperature or rate than I will have this issue.

 
PJmax's Avatar
Group Moderator

Join Date: Oct 2012
Posts: 41,205
NJ

02-04-18, 11:11 AM   #6 (permalink)  
The troubleshooting manual I left is very easy to follow.

The key to that unit starting and stopping is that magnetic flow sensor. It could be checked with an ohmmeter with the AC power shut off. The meter would indicate one resistance with the water flowing and a different resistance with the water not flowing.


~ Pete ~

 
audioi's Avatar
Member

Join Date: Mar 2012
Posts: 60
NY

02-05-18, 04:53 PM   #7 (permalink)  
No change in the resistance with water flowing or stationary so why would the indicators stay on?

 
PJmax's Avatar
Group Moderator

Join Date: Oct 2012
Posts: 41,205
NJ

02-05-18, 05:10 PM   #8 (permalink)  
There needs to be a change. It sounds like the plunger is not returning to its normal off position and the heater thinks you are using water.


~ Pete ~

 
Search this Thread