Replaced Pentair Mastertemp 300 control board, now screen logic doesn't work

[jmturner81]

So I recently diagnosed that the control board of my Mastertemp needed to be replaced. It's not quite 3 yrs old and while the 'pool on' light was lit, none of the red ones were, it wouldn't kick on. The lcd screen was blank as well. So our installer brought over a new board. It's the r14 version and this one has the jumper that looks to enable or disable external control if you have something automated like screen logic (that's my assumption). We put the new board in and I've tried both positions of the jumper. In one, heater runs great but I have to control it from the heater, by setting the temp on the heater. Interesting point here, only the 'spa on' button will turn it on. The 'pool on' button doesn't work. Jumper in the other position disables the 'one buttons as expected but it isn't taking commands from my screen logic. This all worked great before I replaced the board. I've included some pictures. As you'll see, I've got the wires from the panel that screen logic uses. Confirmed they're seated properly. Does the board need to be configured in some other way?

Thanks in advance!

 

[Jimrahbe]

jm,

Where in the EasyTouch do you have the two wires from the heater connected?

Thanks,

Jim R.

 

[jmturner81]

jm,

Where in the EasyTouch do you have the two wires from the heater connected?

Thanks,

Jim R.

Hi Jim, thanks for taking a look. It's connected to J19 on the easytouch panel.

 

[JamesW]

Interesting point here, only the 'spa on' button will turn it on.

The 'pool on' button doesn't work.

The Pool On button is probably defective and the membrane pad is probably bad.

Jumper in the other position disables the 'one buttons as expected but it isn't taking commands from my screen logic.

The jumper is only used when the three wire setup is used. Three-wire connection circled.


Since you are not using a 3 wire control, you leave the JMP 1 in the disable position.

Since the Spa On button works, just push Spa On and turn up the set point to 104 degrees and then you should be able to control the heater from the automation.

Where it says "External Control Interface" is the three-wire connection.

Is your picture flipped in mirror image?

 

[jmturner81]

The Pool On button is probably defective and the membrane pad is probably bad.

The jumper is only used when the three wire setup is used. Three-wire connection circled.

View attachment 351626
Since you are not using a 3 wire control, you leave the JMP 1 in the disable position.

Since the Spa On button works, just push Spa On and turn up the set point to 104 degrees and then you should be able to control the heater from the automation.

Where it says "External Control Interface" is the three-wire connection.

Is your picture flipped in mirror image?

View attachment 351627

James, it's similar yes. And currently it's set to disable 3 wire control. I'm missing the bypass valve and the RS-485 port. I'm curious because everything worked with the previous control board. I'm going to try your recommendation in the morning and set it to 104 and see if the screen logic will work. Thanks!

 

[Jimrahbe]

jm,

ScreenLogic only opens or closes a small relay on the main board.. You can just short the two wires at the J19 heater connection to see if the problem is on the heater side or the EasyTouch side. Basically the EasyTouch just monitors its water temperature probe and compare it to the set point temperature you want the temperature to be.. If the water temp is below the set point the small EasyTouch relay closes, which connects the yellow and green wires on J19. This closes the Fireman's loop and allows the heater to run. The heater will run until the water temp reaches the set point and the small relay opens, and the heater stop heating.

This is why you must have the heater on and set to max temp. It does not matter if the heater is in the Spa or Pool mode...

Thanks,

Jim R.

 

[jmturner81]

Thank you James and Jim, that's exactly what it was. I feel a bit foolish not recognizing that, but happy for the learning lesson and explanations! I really appreciate it. I'm going to see about replacing the membrane pad seeing as how it is still under warranty, but otherwise it's great.

Happy 4th of July!!

 

[JamesW]

Double check the Pool On button.

If the jumper is set to enable the 3-wire control, then the Pool On and Spa On button will be disabled.