Thermostat to Harman p43

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Fireside

Member
Jan 22, 2016
37
Durham
[Hearth.com] Thermostat to Harman p43 [Hearth.com] Thermostat to Harman p43

I just purchased a used 2013 Harman p43 that I found on craigslist. I want to hook it up to a programmable thermostat in order to have it kick on while I am away. I have done some reading and found some information but still don't feel comfortable with the process. Can someone walk me through this. I guess I am worried about messing with my new baby and screwing something up.
 
Hello

I cannot read the bulliten, can you do upload a file in it's regular size?
 
Hello

I cannot read the bulliten, can you do upload a file in it's regular size?

Technical
Bulletin
MODEL
Pellet
3/26/2007
Adding a programmable set back thermostat for all Harman Pellet Stoves
Thermostat must be:
1) Millivolt compatible
2) Gold Contacts
3) Low Voltage
4) Low current
Recommended Honeywell Thermostats.
RTH230B
RTH6300B
These thermostats are available at hardware stores and home improvement retailers.
Note: If there is a jumper between Rh and Rc it must be removed from the thermostat�s terminal block. Use
minimum 2- conductor 24 gauge twisted pair wire to connect the thermostat.
Connect the thermostat in series with the room sensing probe using the Rh and W terminals on the
thermostat. (See Fig. 1) The set back thermostat must be used in conjunction with the room sensing probe
(except the P38).
Thermostat Settings:
Occupied Mode:
In occupied mode program the thermostat to its maximum temperature setting. (i.e. 82 Deg. F) The stove�s
room sensing probe will control the room temperature. Set the stove�s temperature dial to the desired room
temperature. (i.e. 72 Deg. F)
Unoccupied mode:
In unoccupied mode program the thermostat to the desired set back temperature. (i.e. 60 Deg. F) When the
thermostat opens (is satisfied) the stove will go into a 4-blink status. If the stove is an auto ignite stove and
the auto-manual switch is in auto mode the stove will shut down. When the thermostat closes (calls for heat)
the 4-blink status will automatically reset and the stove will ignite.
If the stove is a manual ignite stove or an auto ignite stove with the auto-manual switch in manual mode, the
stove will go into a 4-blink status when the thermostat opens (is satisfied) and the stove will go to a
minimum burn and stay there until the thermostat closes (calls for heat). When the thermostat closes (calls
for heat) the 4-blink status will reset automatically.
Note: A 4-Blink status is described in the owner�s manual. The status light on the stove will blink 4 times,
pause, and blink 4 times continually. This error code is the board recognizing that the room sensing probe is
not connected or has failed. Breaking one leg of the room sensing probe wiring with the thermostat, as we
are doing here, causes the 4-blink status. This error automatically resets when the board recognizes the room
sensing probe has been reconnected.
 
I have a Skytech 3301p wireless remote hooked to our P43. The control box is just wired in series with the room temp probe. Set the stove to run in Room temp/igniter manual (fire goes into maintenance burn mode between thermostat calls for heat). Works great.

Sam
 
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Welcome Fireside! You'll like that P43. Let us know how your set up works out.
 
Here's the best way to do it. No codes! Thanks to 603bob many years back for this
 

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Here's the best way to do it. No codes! Thanks to 603bob many years back for this

That is nice but that just lowers the stove heat at night, not the same as the on/off you get using a t-stat.
 
Here's the best way to do it. No codes! Thanks to 603bob many years back for this
You guys and your wiring diagrams - I am electrically challenged, so have a hard time with those. Here are written directions for those that are like me.

It is easy, even for a non-electrical person like me. I put my P43 on a thermostst (not programmable, but should work the same). You need to go to the hardware store and buy spade connectors (at least 1 male and 1 female). I ended up at Radio Shack and got #6400044 so I had extras (that link will give you the size that will work).

Use 2 wires from you cable (if you have more than two wire, any two will do, just make sure you connect the same colors to the thermostat).
Put a connector on each those two wires that will attach to the stove (use 1 male for one wire and 1 female for the other wire)
Disconnect the left hand wire from the stove (as you are looking at the front of the stove). It will be tough to pull out - just grab as close to the stove and give a strong, steady pull (don't yank)
Connect the female connector you attached to te cable to the stove, push that puppy in firmly.
Connect the male connector/wire of your cable to the disconnected probe wire - once again, push firmly
Connect the other end of the cable to your thermostat's RH & W (using same color wires, but it doesn't matter which wire goes to which connection in the thermostat).
If there are jumpers - you will need to puzzle over your manual several times, but you will eventually get it. Just remember, you are using a heat only device, 1-stage (not 2-stage).

Program your thermostat (if programmable) or at least set temp desired, set stove temp dial to about 80*, turn on thermostat, turn on stove, and walla - you are in business. I have found that my P43 does not work as expected when in Room Temp / manual (the fan doesn't' go on high). But all other modes work the same (except in Room temp / auto - it is controlled by thermostat instead of probe). The stove still behaves as usual if you decide to turn it to Stove temp mode.

Hope this is helpful for those whose heads hurt when they look at the diagrams!
 
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You guys and your wiring diagrams - I am electrically challenged, so have a hard time with those. Here are written directions for those that are like me.

It is easy, even for a non-electrical person like me. I put my P43 on a thermostst (not programmable, but should work the same). You need to go to the hardware store and buy spade connectors (at least 1 male and 1 female). I ended up at Radio Shack and got #6400044 so I had extras (that link will give you the size that will work).

Use 2 wires from you cable (if you have more than two wire, any two will do, just make sure you connect the same colors to the thermostat).
Put a connector on each those two wires that will attach to the stove (use 1 male for one wire and 1 female for the other wire)
Disconnect the left hand wire from the stove (as you are looking at the front of the stove). It will be tough to pull out - just grab as close to the stove and give a strong, steady pull (don't yank)
Connect the female connector you attached to te cable to the stove, push that puppy in firmly.
Connect the male connector/wire of your cable to the disconnected probe wire - once again, push firmly
Connect the other end of the cable to your thermostat's RH & W (using same color wires, but it doesn't matter which wire goes to which connection in the thermostat).
If there are jumpers - you will need to puzzle over your manual several times, but you will eventually get it. Just remember, you are using a heat only device, 1-stage (not 2-stage).

Program your thermostat (if programmable) or at least set temp desired, set stove temp dial to about 80*, turn on thermostat, turn on stove, and walla - you are in business. I have found that my P43 does not work as expected when in Room Temp / manual (the fan doesn't' go on high). But all other modes work the same (except in Room temp / auto - it is controlled by thermostat instead of probe). The stove still behaves as usual if you decide to turn it to Stove temp mode.

Hope this is helpful for those whose heads hurt when they look at the diagrams!

Thanks everyone for the input I greatly appreciate it. Bogieb, I agree, I am not good with electrical diagrams. I have a few more questions. I purchased a Honeywell thermostat (rthl2310b) that says it is millivolt pellet stove compatible. I feel reasonably confident I can do this. I just an wondering does anyone know, the jumper must be removed between r and rc correct? It says in the bulletin something a little different, I am assuming it refers to the same. The bulletin says between rh and rc, the thermostat itself has a jumper between "r" and rc.

In addition the thermostat has a switch to switch from gas/oil or electric or heat pump, which way should I switch the dial?
 
Page 20 says only to remove jumper R and RC if you will use both - don't think you are using both, so should leave it.
I checked my LUX, and the jumper is attached between the two. The version of the manual that the link goes to also, shows alternate tags for wires.
 
I would think that you use the gas/oil setting.
 
Also, you will use the W and RH (or R) - not RC.
 
I would think that you use the gas/oil setting.
EDIT: Definitely use the gas/oil setting - that is the setting for systems that control their own fans (which pellet stoves do).
 
EDIT: Definitely use the gas/oil setting - that is the setting for systems that control their own fans (which pellet stoves do).

Ok so I have the thermostat hooked up and put it in auto ignite and room temp mode. The pellet stove did not start up when the thermostat called for heat. Am I doing something wrong here?
 
Ok so I have the thermostat hooked up and put it in auto ignite and room temp mode. The pellet stove did not start up when the thermostat called for heat. Am I doing something wrong here?

I tried firing up the stove in stove temp mode and then switching over to room temp mode and it just went into four blink status. Very frustrating. I hooked the 2 wires directly from the room sensor into the thermostat on "w" and "r" ..... this seems to work for everyone else???
 
Both wires from the sensor should not be attached to the thermostat. Only the left one (looking from front of stove). Of the two wires from the thermostat - one should be attached to the stove (left receptacle) and the other to the left probe wire.

Hook everything back up the way it was originally, then go thru my instructions again. The second probe wire (on the right) never leaves the stove and never has anything attached.

Here is a picture, hopefully it helps.

[Hearth.com] Thermostat to Harman p43
 
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If you are wired correctly, then the 4 blink status says the temperature has been satisfied, so it shuts down until call for heat. Make sure the thermostat is "on" and the set temp is higher than what the current air temp is. Also make sure your temp dial setting on the stove is way higher than the set temp of the thermostat.
 
If you are wired correctly, then the 4 blink status says the temperature has been satisfied, so it shuts down until call for heat. Make sure the thermostat is "on" and the set temp is higher than what the current air temp is. Also make sure your temp dial setting on the stove is way higher than the set temp of the thermostat.
U can hook 1 wire from sensor to stove, the other wire from sensor to thermostat wire, then the other thermostat wire to back of stove. That's what I have done & it works great !
 
If you are wired correctly, then the 4 blink status says the temperature has been satisfied, so it shuts down until call for heat. Make sure the thermostat is "on" and the set temp is higher than what the current air temp is. Also make sure your temp dial setting on the stove is way higher than the set temp of the thermostat.
I think I did something wrong with the wiring ... go figure .... they temp on the thermostat should have definitely kicked the stove on it clicked over to "heat on" ..... I have it running on stove temp tonight. I am going to re read your instructions again tomorrow and try again. I am good with most things ......but electrical ... well ......not so much.
 
STOVE==================================================================o This is the wire to the temperature sensor with the o being the sensor. Notice there are 2 wires. Cut One of the wires of the 2 somewhere in the middle. This will leave you 2 ends. Connect the 2 ends to the thermostat. Job done. I think you're reading to much into this. Look at electricity like water there must be a supply and a drain for an electrical circuit. Look at the thermostat as a valve. So if you put the valve (thermostat) in one of the lines the water (electricity) won't flow when the valve is turned off. When the thermostat calls for heat the valve will turn on and the water (electricity) flows through the thermostat (valve) into the temperature sensor and out the other wire (the drain).
Hope this helps,
Ron
 
Are you in NH? If so, and can't get it figured out, let me know and I'll see if I can make the trip out there to help out.
 
Are you in NH? If so, and can't get it figured out, let me know and I'll see if I can make the trip out there to help out.

You have been so helpful. Thanks so much. I am in NY. I think I will get it figured out. One question though .... I stupidly cut off the room sensor probe (the black thing at the end of the cord) at the end of the room air sensor cord. Do you think this will affect anything once it is hitched up?
 
I am unsure what ramifications that will have.
 
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