HAI RC2000 Thermostats ">>" Indicator

[HomeTechNewbie]

Hi guys, 
 
Installed 7 RC2000 thermostats in my home.   All were working fine until this morning.   2 of them did not fire up heat this am and I believe it has something to do with the thermostat.   There are 2 ">>" notations next to Heat.   Does anyone know what those mean?  and is there a list of symbols out there somewhere?  I perused the manual but couldn't find anything denoting this.   
 
 
thanks for the help! 
 
Although i don't think it matters, i have automation code, changing the set points throughout the day (3x).

 

[Anthony A.]

I remember i had that issue a few times over the years. I would pull the stat cover off and cycle power to the furnace. Put cover back on and it would reset itself. If that doesnt work, you will need a 24vac power supply board for the stat. HAI sells them.

 

[Desert_AIP]

IIRC that is the symbol for second stage heat.

 

[fcwilt]

The > symbol in front of heat/cool means first stage is active, >> means second stage is active.

 

[HomeTechNewbie]

I might have to try the recycle trick.  its clearly not warming anything.   Thanks! 

 

[HomeTechNewbie]

I might have to try the recycle trick.  its clearly not warming anything.   Thanks! 

 

[fcwilt]

Where your t'stats are connected to your HVAC gear are there any LEDs to tell you what t'stat outputs are active?
 
The second stage call has likely occurred because the room temp was not raised as expected when the first stage call was active.
 
So either the outputs of the t'state are not actually going active OR the HVAC gear is not responding to the t'stat.
 
I had problems connecting my RC-2000 t'stats to a Water Furnace zone controller. Seems the outputs from the t'stat (which are supposed to be dry contact relays) were in some way not quite compatible with the inputs on the Water Furnace zone controller. The installer added relays so that the t'stat controlled the relays and the relays controlled the zone controller. This must be a fairly common problem as HAI makes (when last a checked) a little board with relays to do what the installer did on his own.

 

[Desert_AIP]

Do you have two stage heat?

 

[ano]

Yeah, if you are using a zoned system, does your zone controller take two-stage input?  Some zone controllers can but others can create the stage 2 signal depending upon how many zones are calling, or how long they have been calling for heat. If the zone controller isn't using the second stage signal from the thermostats, then you need to change the setting in each thermostat to single stage.  I DO use the second stage input for my zone controller, and if any thermostat calls for stage 2 the zone controller will set the furnace to stage 2, but the zone controller has to be configured that way. 

 

[HomeTechNewbie]

Odd... but just waited it out and its back to one arrow and heat on... 

 

[Desert_AIP]

One arrow is single stage heat.
Two arrows is second stage heat.
 
So now it stopped calling for second stage heat and is back to calling for first stage heat.
 
I think you T-stat may not be configured correctly.
 
For instance I have a heat pump.
The heat pump normal mode is one arrow, the backup "Emergency" elecrtic strip heaters are the second stage.
 
The T-stat calculates a rate of rise based on the current temperature and the setpoint.
If the first stage heat is not raising the temperature quickly enough, such as a heat pump that loses efficiency when the outside weather is too cold, it calls for the second stage,
 
If your system only has single stage heat, you need to make sure it is configured correctly so it doesn't make the second stage heat call.
If your system does have second stage heat, then you need to ensure the second stage relay in the T-stat is properly wired to the HVAC controller.

 

[mattbuff5]

Just putting this out there in case anyone has similar problems...
 
One additional tidbit that I ran into during the last coldspell in the northeast a few weeks ago is a situation where there is only the "second" arrow displaying.  Aka only there left-most arrow is displayed, so there is a blank space between the arrow and the mode.  This indicates a call for Emergency Heat, which I didi not know at the time.
 
You basically have these options
_>Heat = First Stage Heat
>>Heat = Second Stage Heat
>_Heat = Emergency Heat
 
Also,
D>Heat = Defrost Cycle
 
When I had questions, here is HAI's Technical Support Response to me - the important part is the Rate of Rise of 5 degrees per hour...
 
Matt, that makes sense. With a dual fuel heat pump, the compressor and furnace should never run at the same time. The way it works is this. You have upper and lower Balance Setpoints – by default on our Tstats, 35 and 45 degrees F. When the OD temp is above 45, the compressor runs only. When the OD temp is below 35, the furnace runs only. When the temp is between 35 and 45, the compressor runs. The Tstat looks for a rate of rise of 5 deg/hour. If the compressor cannot satisfy the rate, the compressor turns off and the furnace runs until the rate is correct. Then the furnace turns off and the compressor turns back on.