Need thermostat replacement for HAI Omnistat


I'm a homeowner an Elk M1G installed myself in 2009, with the serial interface and HAI Omnistat thermostat. Recently I had the 30 year old furnace replaced, and coincidentally the thermostat stopped working. The furnace contractor confirmed it stopped sending the call for heat to the furnace, which is really important for a thermostat to do. It's too coincidental that it would happen simultaneously, but whether it was the furnace installer or not, I still don't have a working thermostat.
Since my original install, HAI was acquired by Leviton.  I purchased a Leviton Omnistat from Amazon, and when it arrived and I connected it, it was faulty. The LCD screen was garbled, and would freak out every time you turned the control dial.  I returned it to Amazon for another, which was also faulty.  I returned them both to Amazon for a full refund. Clearly the quality under Leviton is not as good. 
Before returning to Amazon, I did try to resolve it with Leviton.  Leviton was completely useless, not returning calls, no support. I have no confidence that Leviton actually makes a working product. So I need to know what alternatives there are.  
I'm trying to stay with thermostats that use the M1 serial interface, because I have an existing investment in the serial interface. I don't have a Zwave in this house. This is a vacation home, so I need something very reliable.  But if ZWave is my best most economical option, I could go that route.
Thanks for the advice.


Active Member
I've always used Omnistats, never had an issue with them. Are you sure you're connecting them correctly? I say this, because two in a row, seems a little weird. I've had them go bad after X amount of time, but never came bad out of the box.
If you want, I have an extra omnistat rc1000 and also a RC-2000 I could sell you, and show you pictures that it works. We can try those and see what's up..


Active Member
While I haven't tried to go through Leviton recently, you want to be dealing with the New Orleans group for OmniStats.  They are pretty small and if you hit them near the holiday recently you might have not gotten a response very fast.
Check here:
The (Call 1-800-824-3005 OPTION #8) should go to them.  They should be able to repair or replace your old OmniStat for a reasonable fee.
I bought a used one off eBay and called them for repair when the serial seemed to be dead.  They said unrepairable but offered a reasonable trade in price on a new unit.


I did not mention earlier, but this Omnistat is installed in my vacation home, not my primary residence. When I bought the house, I replaced an existing ADT burg alarm with the Elk M1G + Omnistat.  It's been a great solution for the past 9 years. Obviously, I'm not there all the time, and I use the Elk controlled Omnistat to turn up the heat when I begin driving.  It was really convenient when our kids were really young to arrive to an already warmed up house. 
I suspect the furnace install is what fried my original HAI, but it's no use crying over spilled milk.  Because this is a vacation home, I need a reliable T-stat to get me thru the winter, so I got the cheapest $14 manual T-stat I could for now. I didn't have time to futz around with unreliable solutions worried if the Omnistat will stop working while I am not there, all during the heating season.  I went 'up north' in November, which is when I tried installing the second Amazon replacement, which also had a faulty even less readable screen.  I'm just going to have to rely upon the cheapy T-stat until the heating season is over. But, when it is, I want to be prepared to replace it. The question is, replace it with what?  I've already got the Elk M1G + serial interface, all working perfectly.  The Elk actually was controlling the original HAI Omnistat just fine. But the Omnistat stopped sending the call-for-heat (bad relay?) coincidentally one or two days after the new furnace was installed (in August). 
Well, anyway, that's my story. 
@Cobra Thank you for the advice. It was not around the holidays when I bought them from Amazon. I bought in Sep and Oct. I may try calling the number you provided and see if I can get thru to them for repair.  I did get a phone number for New Orleans after being bounced around from person to person to person. I don't know if it's the same number you provided, so I'll give it one last try.  If it doesn't go well, I need some alternative solution.
@ComponY Yes, I'm sure I'm connecting it correctly.  The screen is all corrupt. Check out the picture on my Amazon review. Parts of the screen were legible, but as you would rotate the control knob, different rows of pixels would go haywire. Amazon's reviews on the RC-1000WH are negative right now (including mine), and there are reports on Cocoontech other forums of defective Omnistats.  Respondents say, "I'm going to guess you bought it on Amazon."  When I was working on the phone with the Amazon return department, the representative was aware of many returned purchases. I don't know if Amazon got a shipment of fraudulent knock-offs, or if Leviton quality has really suffered. In either case, I'm skeptical that I'll get one that actually works for any length of time.  Because this is a vacation home, I need something I can depend on.
IMHO the Leviton acquisition of HAI has not been a positive thing for consumers. 
Thank you all for your assistance.


Senior Member
I know you said you want the Elk integration - I had that in my last house... but now I use Ecobee and I like it - and I do have remote access...  just sayin', you may not need to stick with Elk integration to keep the ability to turn it on remotely.  I don't pay any monthly fees.


@Work2Play, I appreciate the recommendation.  Because this is a vacation house, I don't have internet or Wi-Fi. I'm sure the Ecobee is great, but not going to work for my application. 
@viroid, I also found that information on Elk's web site.  It fails to mention WHICH communicating thermostats it's compatible with.  The RCS, for example, when you look at their products, they no longer make a communicating hard-wired T-stat. RCS only mentions Zigbee, ZWave and Wi-Fi. If I could find someone selling a compatible RCS hardwired T-stat, I'd buy it. But Elk doesnt tell you which models are compatible. Does anyone here know? 
For Aprilaire, the Elk web site links to a dead Aprilaire web site. The M1 web page at least mentions it's compatible with the 8800 or 8870.  But the M1 page mentions that it needs a T-Stat, and RS232/RS485 protocol adapter, and an Aprilaire 8818/8819 distribution panel. This highly scaleable system can grow to 8 or 16 or more T-stats.  I have one T-stat. 
Does anyone know if you can connect the M1XSP directly to the Aprilaire 8800?
Any ideas?