Lost zone 2 Dometic 15k five button remote

[birdhunter]

So it's 100° I go out plugged into short power leaving both my 15K dometics going. I come back an hour and a half later and the rear zone number two is gone from the remote screen and the air conditioner is not running. I reset the five button remote only one zone zone one comes up. No breakers have flipped. Is this the remote? Or is this the board in one of the roof AC units? If so which one? Yes I checked the phone plugs at the rear AC unit they're fine.

[followingsea]

Originally Posted by birdhunter

So it's 100° I go out plugged into short power leaving both my 15K dometics going. I come back an hour and a half later and the rear zone number two is gone from the remote screen and the air conditioner is not running. I reset the five button remote only one zone zone one comes up. No breakers have flipped. Is this the remote? Or is this the board in one of the roof AC units? If so which one? Yes I checked the phone plugs at the rear AC unit they're fine.

If you still have 120 vac at the rear A/C, here is how I solved the problem.

https://www.irv2.com/forums/f54/zone...cc-538732.html

Of course you have the newer 5 button control station so your setup is different but here are some things to check.

Each control card in the A/C unit has a fuse in the 12 vdc circuit. To get to it you have to take the inlet panel off. Since you said the phone plugs are good you have already removed the panel.

In my case, there was 12 vdc at the front A/C unit and not at the back. Therefore zone 2 was 'gone' from the control station.

[birdhunter]

Originally Posted by followingsea

If you still have 120 vac at the rear A/C, here is how I solved the problem.

https://www.irv2.com/forums/f54/zone...cc-538732.html

Of course you have the newer 5 button control station so your setup is different but here are some things to check.

Each control card in the A/C unit has a fuse in the 12 vdc circuit. To get to it you have to take the inlet panel off. Since you said the phone plugs are good you have already removed the panel.

In my case, there was 12 vdc at the front A/C unit and not at the back. Therefore zone 2 was 'gone' from the control station.

Thanks followingsea, but that would not work for me since I have a hurricane that's run off the same remote. I've had no trouble with this thing in 13 years. I left where I was and drove for two and a half hours and when I got here, I reset the five button remote again and zone 2 is back! I don't get it. Something's wrong but I'm not sure what.

[2dogsbarkin]

Mine did that in the winter and had no heat, Found after 2 days searching the phone plug in the back of the thermostat was bad, cut it off and installed a new one. I did have to buy a crimp kit at Lowes.
just a thought

[rffowler55]

The phone cables carry the signal so if it is working sometimes and not others then it potentially is a build-up on the phone cable connectors that might not be apparent. I have had success spraying the phone cable ends and the connector it plugs into with 'electronic contact cleaner'. If that does not work then replace the plug as recommended.

[followingsea]

Originally Posted by birdhunter

Thanks followingsea, but that would not work for me since I have a hurricane that's run off the same remote. I've had no trouble with this thing in 13 years. I left where I was and drove for two and a half hours and when I got here, I reset the five button remote again and zone 2 is back! I don't get it. Something's wrong but I'm not sure what.

My fix will work because it is replacing failure prone electronics with reliable local manual controls.

Your A/C is designed to work that way.

Replacing plugs and spraying contact cleaner may work until the next failure point pops up.

[DJ55]

When my back A/C stopped working it was the phone cable between the front and rear units and it was that cable's connection at the front unit that was the problem. In my case I just had to clean the front connection and re-connect it firmly. It's been working fine the 2+ years since.

[birdhunter]

Thank you all, this is very helpful. It's still working but I'm going to follow your advice and use contact cleaner on every phone connection in the system, starting with the thermostat.