Harman Room Temp Sensor Placement? Thermostat?

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bjb4d5

New Member
Dec 16, 2019
9
Kansas
I recently purchased a used Harman p68. I got it home and immediately ran a tube under my garage door and fired it up...and it's fantastic. I had posted earlier about hooking up a thermostat to it. However, now that I have used it a little and noticed how accurate the room temp sensor probe is. I'm just curious what other people have done to "hide" this in their install. I am remodeling my basement (it's down to the studs) and was just curious what other people have done/wished they would have done on this. I am still open to putting in a millivolt thermostat, but I could also extend the probe wire with 18/2 thermostat wire and run it 20 feet away from the stove and have it exposed behind a picture or something on the wall. Whats the best way to do it for the stove?? I have heard of 4 blink errors on the machine running with a thermostat and also that the probe still needs to be intact when splicing for the thermostat? The machine will not shut down completely with thermostat attached?? Just want to have the most efficient and best install for heating my basement and some of my upper floor. (Basement is roughly 1800/2000 sq feet give or take). Currently not finished, but it will be. Wouldn't have bought the stove without the help of people on this forum. Thank you!
 
Unless a customer insists that they want the probe run out to one side or the other, I coil it up and let it hang where it plugs in. The coolest spot in a room with a p68 will be behind the stove
 
You have a couple of choices. If you want a programmable but dont require the wireless / app capability, you can just hook up a millivolt - battery operated thermostat. The probe and thermostat is just wired in series with 2 wires from stove. I placed the probe in the thermostat, it does not matter where it lives, its the thermostat itself that will switch the stove on and off, the probe is required to complete the circuit. The stove will shut down when no call for heat from the thermostat and its cool down has completed.
If you want to have wireless control from an app, still with wires to the stove, most require 24v from the stove but you can get some that run on batteries or uses an adapter (not that I have tried that) that works over 2 wires. You are better off running 4 wires to the thermostat but still wire the probe in. I am using a Lux Geo after our electricity supplier were offering them cheap, works well.
 
There's no good reason for using either one in my opinion. It's a matter of personal preference. If you want programmable features then a Thermostat is the way to go. My p43 works fine on the probe but I run on a thermostat simply because the p43 uses the exact same thermostat as the house furnace. My wife can run it exactly like the furnace.
Ron
 
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There's no good reason for using either one in my opinion. It's a matter of personal preference. If you want programmable features then a Thermostat is the way to go. My p43 works fine on the probe but I run on a thermostat simply because the p43 uses the exact same thermostat as the house furnace. My wife can run it exactly like the furnace.
Ron

I use an in-line, millivolt thermostat for my main floor stove because I am heating my whole house from one end and the layout is far from open concept. I want the middle of the house (my office), to be at 69* - that will keep the far rooms at 66-67*. I tried using the probe and finding the "sweet spot" for my situation, but it didn't work very well. So, thermostat was the way to go for me. I just have a basic, non-programmable thermostat and if I feel slightly chilled while working in my office, it is easy just to bump it up to 70*, and I'm good then I bump it back down to 69*.

I have heard of 4 blink errors on the machine running with a thermostat and also that the probe still needs to be intact when splicing for the thermostat? The machine will not shut down completely with thermostat attached?? Just want to have the most efficient and best install for heating my basement and some of my upper floor. (Basement is roughly 1800/2000 sq feet give or take). Currently not finished, but it will be. Wouldn't have bought the stove without the help of people on this forum. Thank you!

You'll always get the 4-blink when the stove isn't running. That is because the stove knows that the probe isn't plugged in normally. Doesn't affect how it runs off the thermostat.

The stove will shut down on a thermostat as long as you have it in room temp / auto.
 
I use an in-line, millivolt thermostat for my main floor stove because I am heating my whole house from one end and the layout is far from open concept. I want the middle of the house (my office), to be at 69* - that will keep the far rooms at 66-67*. I tried using the probe and finding the "sweet spot" for my situation, but it didn't work very well. So, thermostat was the way to go for me. I just have a basic, non-programmable thermostat and if I feel slightly chilled while working in my office, it is easy just to bump it up to 70*, and I'm good then I bump it back down to 69*.

The stove will shut down on a thermostat as long as you have it in room temp / auto.

So do you still use the sensor? Is the thermostat installed in-line, just to break the connection of the sensor, where you would get the 4 blinks?
 
Mine sits behind the stove and keeps my place within a couple degrees of what the stove reads....P61
 

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probably cannot see it but it is peaking out on the left side of the top of the hopper right behind the harman tool.
IMG_1737.JPG

been there for 6 yrs as what was said previously that behind your stove is the coolest area in your room.
 

See my observations/experiences here; post #3.
 
So do you still use the sensor? Is the thermostat installed in-line, just to break the connection of the sensor, where you would get the 4 blinks?
It is installed in-line and you get the 4 blinks.

Thermostat wired to P43-close.jpg
Thermostat wired to P43-notated.jpg
 
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I hooked mine up similar to bogieb, only difference is I placed the room sensor at the t-stat location across the room from the stove, my basement is unfinished but you should still be able to do it @ the t-stat location without difficulty. I didn't like the pellet use with the t-stat trying to control the stove, but some do, just make sure you have an adjustable differential on the t-stat as you will need the swing. I still use my programmable but now only as a setback t-stat for night & in the middle of the day; I set it higher than the stove temperature setting for all hours except the setback hours, this also allows for override adjustments without messing with the stove settings if there is a warm day where you don't want the heat. The Harman probe is actually very good at maintaining temp & balancing pellet use.
 
I never cared for the room temp sensor, in my application.
It just never seem to work like an actual thermostat... for me.
Always seemed to lag some. Both ways.
So I always used stove temp setting.

I had a thermostat on my shop stove.. (Lux) that I never used.
So for the heck of it, I installed it in the house on my Harman.

I have been using it during some of the milder weather (30° type days)
and have to say I really like it.. When it gets 'really' cold,
I will go back to the stove temp setting, as I like heat coming from it
100% of the time.. But today... worked really slick..

Dan
 
I never cared for the room temp sensor, in my application.
It just never seem to work like an actual thermostat... for me.
Always seemed to lag some. Both ways.
So I always used stove temp setting.

I had a thermostat on my shop stove.. (Lux) that I never used.
So for the heck of it, I installed it in the house on my Harman.

I have been using it during some of the milder weather (30° type days)
and have to say I really like it.. When it gets 'really' cold,
I will go back to the stove temp setting, as I like heat coming from it
100% of the time.. But today... worked really slick..


Dan

I turned the P43 to stove temp this morning as it is in the low single digits and the far side of my house will get colder than I like (over the unheated garage). Also, during these temps, the stove will shut down for about 15-30 minutes, then start back up again. Once the sun comes out, or it warms up to the mid teens, I'll turn it back to thermostat regulation.
 
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