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E195 Says R connection, got it rewired

Kennesawlen
Community Member

Hi All:

After more than a year of use our Nest Thermostat E seemingly lost connection to the furnace. Got an E195 code and mentioned R. We found that if we turned off the manual emergency swtich to the furnace waited a minute or then turned it back on, everything returned to normal. For a while. Our furnace guy came by. Looked things over, could not find a problem. Replaced the old furnace emergency manual on and off switch. Worked for a day or two, then he same problem. Everything runs find a day or so and then stops running. When we flip the furnace switch off and then on, it  goes back to working fine again for a while until it doesn't. Furnace guy came back and rewired the old wiring from the furnace to the Nest. Worked fine, looked like it was fixed, until it cut off again. And as before we flip the furnace switch and it runs again until it doesn't. We are not sure of other options. Could it be the Nest is just not working and needs to be replaced although it is relatively new? Are others having the same issue?  

Thanks for any help you  can provide. 

 

2 Recommended AnswerS

Kennesawlen
Community Member

is this the information you need? Thanks. 
Thermo products

No.  AE526755

Model. OL16-125

 

View Recommended Answer in original post

Hello RomandsonAC:

Well, we hooked up the C common wire. The display  showed R power, W1 heat, C 24V common. But alas that didn't work. Instead we got a new error message: E159: No power to common (c) wire detected. So alas we gave up. We think maybe the Nest is not compatible with our 30 some year old furnace. Any how, we pulled the Nest and installed an old analog like thermostat, which we we reset by hand each night and morning. Thanks again for all your help. I wish the outcome had been better. Your advice corresponded with other advice we received so who knows why it didn't work, but it did not. Thanks again. 

View Recommended Answer in original post

14 REPLIES 14

RomanandsonAC
Community Member

Are you running in cooling or heating? Normally if you're running in cooling the E95-error or no power is caused by the emergency overflow switch is being engaged. Your thermostat should be wired through the float switch so if the drain is clogged it will kill the system to prevent it from overflowing water into the house. If you are using in heating I'm not sure what your issue is without additional details. Sorry wish I had a better answer for you.

Kennesawlen
Community Member
We have no air conditioning, just a hot air furnace. We live way up north. So having a furnace/thermostat that cuts off periodically could be really bad, especially if we are not around. Just two wires go into the thermostat, one to R and one to W1. It worked fine for more than a year, now it works for a while. Then it shuts down and we get the error message. We turn the furnace switch off and then on and everything is back to normal for maybe a couple of hours or even a day or so and then it shuts down again with the error messages E195 error message and "no power to R detected." 
 
 Thanks for any help anyone can provide:
 

 

 

So if you have no AC and you have only two wires feeding the furnace correct? If that is the case you maybe short one wire. I know it worked before. But to power the nest, optimum is to have the R(red) and C(common) to power the thermostat. Then what the thermostat does is use the R to switch energizing devices. So for example, if you had AC, you would have the R, C, Y, and G. Red is power, C is common to transformer and every relay, Y would be cooling, and G would be fan, or blower. The C wire would be common to each device you want to energize. So the relay that powers the fan would have a common wire, as would the relay /contactor for cooling. The thermostat when set to call would shift the red wire to the fan relay and complete the circuit and bring on the fan, additionally the red sire would shift to Y to bring in the relay/contactor to bring in the cooling. What it appears like that you have been using the nest almost like a light switch, but instead of turning on a light,  you're bringing on heating and fan simultaneously. Normally you should be able to control each independently. Fan only, or fan and heat together. I'm trying to think of what you could potentially do to  bring on the furnace and still power the nest. Is there any chance you could run an additional two conductors(2 wire thermostat wire)? If possible could you provide the furnace info, model # Serial #. It would help me so i could look up the schematics and possibly come up with a solution for you.  

Kennesawlen
Community Member

is this the information you need? Thanks. 
Thermo products

No.  AE526755

Model. OL16-125

 

RomanandsonAC
Community Member

Sorry for the delayed response but I' m located in Florida and with the heat my days are longer than normal. Sorry for another question but if you can send me the make. I'm still going to see of I can find with model number provided

 

RomanandsonAC
Community Member

I think I found it, is it a Thermo pride OIL FIRED LOWBOY FURNACE

RomanandsonAC
Community Member

Here is the thermostat wiring 
1
I. BLOWER CONTROLLER INFORMATION
A. TERMINAL DEFINITIONS & FIELD WIRING
Burner Harness Connector P1
Pin 1 – Limit switch connection.
Pin 2 – 120 VAC Line connection.
Pin 3 – Burner pilot contact.
Pin 4&5 – 120 VAC Neutral connection.
Pin 6 – Burner pilot contact.
Pin 7&8 – From oil primary control.
Pin 9 – Limit Switch Input (LSI).
Field Wiring to Burner
Pilot (Tstat) Neutral Line
Harness Wires
Beckett Connections
Riello Connections
Yellow Wires White Red
T-T terminals White Black
T-stat terminals White Black
Thermostat/Humidistat connections
"C" Common/ground
"W" Thermostat call for heat
"R" 24 VAC to thermostat
"G" Thermostat call for fan
"Y" Thermostat call for cool
“DEHUM” Humidistat call for dehumidification (TXV systems ONLY)
Thermostat/Humidistat connections for 2-Stage control
"C" Common/ground
"W1" T-Stat call for heat (low fire)
"W" T-Stat call for heat (high fire)
"R" 24 vac to T-Stat
"G" T-Stat call for fan
"Y" T-Stat call for cool
“DEHUM” Humidistat call for dehumidification (TXV systems ONLY)
ECM control outputs
Pin 1 - Speed Common Pin 4 – Blower Enable
Pin 2 - Speed Output Pin 5 – COOL Enable
Pin 3 – Motor CFM Pin 6 – “R” Output
Male quick connect terminals.
"S1-3” 120 VAC Hot
“N1-7” 120 VAC Neutral
“EAC” Electronic Air Cleaner (120 VAC) connection.
“HUM” Humidifier connection (120 VAC).
"FAN" Fan On Signal
“X” 24VAC from transformer.
“C” 24VAC common from transformer.
"CC" Compressor Contactor

It didn't paste very well so here is the link to the installation manual: http://www.thermopride.com/wp-content/uploads/MO-460.pdf
 

RomanandsonAC
Community Member

Here's the manufacture web site

http://www.thermopride.com/

 

Hello RomandsonAC:

Thanks for all your work on this. Consensus is that Nest Thermostat E needs continuous power which connecting the C -- common wire should fix. I think I have this part right, it ran for a long time with no problem but the battery eventually never got the full charge it needed and then would periodically cut off. When we turned the furnace back on manually that provide more power to the battery to get it going but not enough to get it the charge for long term continuous operation. As I said I think I got that right. But any rate two other people we contacted plus RomanandsonAC here said the same thing, connect wire C. So that is what we are doing today. We will let you know here after a  couple of weeks of running if that solves the problem. Again thanks so much RomanandsonAC for all your help here. 

MelbaDT
Community Specialist
Community Specialist

Hey Kennesawlen, 

 

We're glad to hear that you've got it up and running with the help of RomanandsonAC. 

 

Feel free to reach out again if you need more help. 

 

Best, 

Melba

Hello RomandsonAC:

Well, we hooked up the C common wire. The display  showed R power, W1 heat, C 24V common. But alas that didn't work. Instead we got a new error message: E159: No power to common (c) wire detected. So alas we gave up. We think maybe the Nest is not compatible with our 30 some year old furnace. Any how, we pulled the Nest and installed an old analog like thermostat, which we we reset by hand each night and morning. Thanks again for all your help. I wish the outcome had been better. Your advice corresponded with other advice we received so who knows why it didn't work, but it did not. Thanks again. 

MelbaDT
Community Specialist
Community Specialist

Hey Kennesawlen, 

 

Thanks for keeping us in the loop although the outcome is not the one we're hoping for. Still, thanks for trying. 

 

Feel free to reach out again anytime you need us, we'll always be here. 

 

Cheers, 

Melba

MelbaDT
Community Specialist
Community Specialist

Hi, 

 

I haven't heard from you in a while so I'll be locking this thread if there is no update within the day. Should you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community.

 

Best, 

Melba

MelbaDT
Community Specialist
Community Specialist

Hey folks, 

 

Thanks for taking the time to answer to this, RomanandsonAC — this is greatly appreciated. 

 

Kennesawlen, I'm just dropping by to ensure everything is covered here. Feel free to let us know if you still have some questions in mind. 

 

Best, 

Melba