OmniLogic Comm Loss

Timmy81

Member
Sep 21, 2019
11
Southeast Texas
I keep getting this alarm code and need help resolving it. MSP_DEV_COMM_LOSS, Comm Loss Device: 01-46-01-0b-49 HUA:MP. Pool pump is operating fine, waterfall operating fine, valves for spa operate fine. I replaced a water temp sensor and an air temp sensor because they were not working. Now the darn thing reads an air temp of -86 and a pool temp of 166 degrees. Cannot run the spa because the heater will not com on due to the water temp sensor reading so high. No way to calibrate the sensors. Any help in resolving would be great.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
9,758
Northern NJ
Welcome to TFP.

Without knowing the details of your pool and equipment it is difficult to diagnose a problem. Please put details in your pools in your signature.

Are you sure you got the correct part number temperature sensors? Did you cut or splice the cable to the temp sensors?

Put a multimeter on the temperature sensors and test the ohms and see if they are around 10K ohms.
 
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Timmy81

Member
Sep 21, 2019
11
Southeast Texas
Welcome to TFP.

Without knowing the details of your pool and equipment it is difficult to diagnose a problem. Please put details in your pools in your signature.

Are you sure you got the correct part number temperature sensors? Did you cut or splice the cable to the temp sensors?

Put a multimeter on the temperature sensors and test the ohms and see if they are around 10K ohms.
The pool is a Hayward Omnilogic., the sensors are the correct ones and they are reading the same as the old ones; I thought the old ones were bad so I had them replaced while replacing a light. Nothing else is wrong with the pool, even when the error shows up. It still runs, the valves change, blower for the spa works, all controls, lights etc work. Because the temps are reading high, the spa heater will not work normally off the controls of the pool, I have to start it manually.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
9,758
Northern NJ
Get two 10k ohm resistors and install it in place of the temperature probes. If the board is good it should read 77 degrees.

The sensor is 10k ohms at 77 degrees. If you connect the resistor as the sensor, the temperature should read 77 degrees.

@JamesW other ideas?
 

JamesW

TFP Expert
Mar 2, 2011
16,343
Reverse the connectors at the terminals to see what happens. Put the air temperature sensor wires in the water temperature sensor terminals and the water temperature sensor wires in the air temperature sensor terminals.

Make sure that you're not getting wire insulation trapped in the terminal.

You can get 10k ohm resistors online or at some local stores.

How old is the Omnilogic?
 

Timmy81

Member
Sep 21, 2019
11
Southeast Texas
Reverse the connectors at the terminals to see what happens. Put the air temperature sensor wires in the water temperature sensor terminals and the water temperature sensor wires in the air temperature sensor terminals.

Make sure that you're not getting wire insulation trapped in the terminal.

You can get 10k ohm resistors online or at some local stores.

How old is the Omnilogic?
about between 4 & 5 years
 

JamesW

TFP Expert
Mar 2, 2011
16,343



Turn off power and recheck all wire connections. Pull off the terminal blocks and reinstall them.

Make sure that the firmware is updated to the latest version.
 

Timmy81

Member
Sep 21, 2019
11
Southeast Texas
I
I just stuck the air temp sensor in a glass of ice water and the temp went from 127 degrees to 79 degrees. Is it possible that the temp sensor is the wrong one?
 

JamesW

TFP Expert
Mar 2, 2011
16,343
It might be the wrong one, or defective or the connection might be bad or the board might be bad.

Try some of the previous suggestions.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
9,758
Northern NJ
I

I just stuck the air temp sensor in a glass of ice water and the temp went from 127 degrees to 79 degrees. Is it possible that the temp sensor is the wrong one?

What part number did you get? Where did you get them?

But the wrong part would not explain why you say you connected the old temperature sensors and got the same results.
 

Timmy81

Member
Sep 21, 2019
11
Southeast Texas
The only thing I can think of is it must be the board. I put the old sensors back and I am still at -87 degrees for Air temp and 127 degrees for the water temp. before I kicked it back on, I updated the MP firmware, reprogrammed and still get the same readings. Everything works except for the heater and I do not have it programmed because it would not start up anyway given the high temp reading. I swear I am at a loss.
 

CPS Reno

In The Industry
Feb 6, 2019
33
Reno, NV
I 100% agree with JamesW in that you need to updated your system with the latest firmware. We've found MANY issues lately that were solved by the updated version. I wouldn't do anything until you update. Another "free" fix to try is to delete the entire configuration and install it again, from start to finish in one shot. The software is a little touchy lately and these two simple things have fixed numerous little issues for us.
 

Timmy81

Member
Sep 21, 2019
11
Southeast Texas
I 100% agree with JamesW in that you need to updated your system with the latest firmware. We've found MANY issues lately that were solved by the updated version. I wouldn't do anything until you update. Another "free" fix to try is to delete the entire configuration and install it again, from start to finish in one shot. The software is a little touchy lately and these two simple things have fixed numerous little issues for us.
I'm back in town now and placed the resistor in the air temp slot that was reading -87 degrees, while the pool temp read 127 degrees. Funny though, on the app the air read 169 degrees and the pool temp read 127 degrees. Put the resistor in and the are temp read 127 degrees and the pool temp read 156, then went to 127 degrees, I updated the software the other day and reconfigured the system, but that did not work, so what am I missing?