Micro-Air Easy Touch Thermostat issue in Serenity (possibly Unity)

[hoosierrun]

I posted this elsewhere as a 'tag on' post in the LTV Unity board (Dometic Thermostats), but felt that it needs to be here too for more exposure.

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I wanted to report on a problem I have with the Micro-Air Easy Touch Thermostat which I installed in my Leisure Travel Van Serenity about 2 weeks ago. First let me say that it does everything that it was designed to do including complete remote and local control of all HVAC functions plus many other nice-to-have features. The problem I noticed after 2 days of using it, is that it creates RF interference to the lower TV channels. Apparently there is circuitry for the internal power supply that is causing this. I have my TV in the LTV Serenity pre-scanned to my local TV stations in the Tampa, FL area where I reside. After installing the thermostat, I was no longer getting any of the lower channels. I initially did not suspect the thermostat as being a problem, but after hours of troubleshooting, I found that if I lifted one of the wires off the thermostat, the TV stations immediately came back. It is not a matter of turning the thermostat off, because the internal power supply remains active.

I contacted Micro-Air and they immediately sent a replacement unit by Fed Ex, however, when I hooked it up, I have the same problem. The conclusion is that there is a design flaw within their unit that is very subtle. They suggested I might have a bad pre-amp or bad coax cable, but I don't think so. With the old Dometic thermostat re-installed, I can receive about 90 channels, mostly crystal clear (many junk shopping, Spanish, Religious, etc), but our main network channels for football games, weather channel, news, PBS ,and network programming mostly all fall in the 2 to 13 channel range. The thought of trying to replace the motorhome coax cable, pre-amp, antenna, etc. is way overwhelming and I doubt it would change a thing. Sadly, I will have abandon this project. So why are there not other people with the same problem? Perhaps there is a problem but people don't know about it yet. It is not really easy to make that correlation between loss of OTA TV channels and a new technology thermostat. I can only speculate the the RF interference is entering directly into the roof top antenna and at a level that is higher than the received signal. It is not a matter of degrading the signal to where I see pixels..... the interference totally obliterates the signal and the TV reports 'no signal'. Looking at this further, I see that the roof top (Wineguard) antenna is only about 3 to 3-1/2 feet away from the thermostat and the roof is fiberglass. I doubt that the problem would exist if the roof was metal and that is likely why there are not other complaints.Bottom

Micro-Air has no intention of re-designing their product at this time based on my complaint alone. Part of the purpose of my post here is to make people aware of the potential problem and see if anyone else that has installed one of these units is experiencing TV reception problems in the lower channel range. If it starts to come to light, Micro-Air may take steps to add shielding to their thermostat power supply. I am really disappointed because this is a really cool product.

 

[NomadJay]

I have the same Micro Air thermostat in my 2018 Serenity, but I don't watch TV (only stream youtube, etc.) so I haven't noticed this problem. Perhaps the Bluetooth transmitter on the thermostat is causing this interference. Try disconnecting from it on your phone maybe to see if that helps. For what its worth, I never connected mine to bluetooth. Actually typing this out, maybe the Micro Air unit connects to your phone via WiFi (not Bluetooth and that is the issue..? I've also never used that option.

 

[hoosierrun]

I have the same Micro Air thermostat in my 2018 Serenity, but I don't watch TV (only stream youtube, etc.) so I haven't noticed this problem. Perhaps the Bluetooth transmitter on the thermostat is causing this interference. Try disconnecting from it on your phone maybe to see if that helps. For what its worth, I never connected mine to bluetooth. Actually typing this out, maybe the Micro Air unit connects to your phone via WiFi (not Bluetooth and that is the issue..? I've also never used that option.

I've done quite a bit of work trying to resolve this with only partial success. The Bluetooth and Wi-fi don't seem to come into play here. It appears to be the thermostat internal power supply that is generating RF interference. I can take an FM radio and tune it to 88.5 (one of our local stations) and as I move it toward the thermostat, the programming is obliterated and I just hear noise. I talked with Micro-Air and suggested trying some low pass electrical filters on the three lines. They said I could try it. I ran shielded control cable to the filters and mounted them behind the closet panel. I am now able to pick up 2 of the 4 local channels in Tampa, so it was a partial success. I presume the rest of the interference is radiated through the air and picked up by the antenna.