Harman Room Temperature Sensor, 3-20-00906

SKU 3-20-00906
MPN 3-20-00906


Harman Room Temp Sensor Part #3-20-00906 (For Stoves Without Touchpad Control)

This is a room temperature sensor for Harman Pellet Stoves. View our huge selection of Harman stove parts. With over 10 years in the stove industry, we know Harman stoves and we can help you order the correct temp sensor as well as all your other Harman stove parts.

What do I do if the status light blinks four times?

Four blink status lights errors are caused by a failure to maintain an electrical circuit through the room sensing probe. If the probe is not connected to the stove, if a crimped wire connection on the room sensing probe is faulty or if the sensing probe wire or resistor at the end of the wire is damaged, the stove will immediately display the 4 blink error code when the stove is attempted to be used on “Room Temp” mode. If you get this error code please note that you can still use the stove on the “Stove Temp” or “Constant Burn” mode, however; the stove will not turn off and on or modulate up or down as the desired room temperature is reached.

If the room sensing probe is plugged in and you get this error, replace the room sensing probe.

Accetra Inserts (Excluding the Accentra 52i) and the P35i require the installing technician to cut the ¼” factory crimped wire connections from the ESP probe and install 1/8” connections supplied in the installation kit. It’s very common for installers to use pliers to make these crimped connections instead of actual crimpers and sometimes the wires will slip out of the connections if the proper tools weren’t used. If this is the case, simply install new connectors.


Replacement For Part Number :
  • 3-20-00906

Compatible Models


  • Accentra 52i
  • Accentra Cast Free Standing
  • Accentra Insert
  • Advance
  • HF60
  • Invincible Insert
  • Invincible RS
  • Invincible T
  • Magnum Stoker
  • P35i
  • P35i-C
  • P38
  • P38+
  • P43
  • P43-C
  • P61
  • P61-C
  • P61A
  • P68
  • PB105
  • PC45
  • PF100
  • PF120
  • XXV

Technical Specs

Length of wire 60 inches
Standard Type 18-2 thermostat wire


Assembly Instructions For Harman Room Temperature Sensor, 3-20-00906

Use standard 18-2 thermostat wire to extend the distance to the desired location (50' maximum). The room sensor should be installed in the location where you want to control the temperature. In most installations locating the room sensor behind the stove near the distribution fan works well because the sensor monitors the room air being drawn into the distribution fan.

NOTE: Distances of more than 25 feet from the unit or in another room are not recommended. The room sensor is essential for the P61A's excellent efficiency.

Helpful Tips

The room sensor is a small temperature sensor on the end of a 60" wire. This sensor is installed much like a standard wall thermostat. Because it is so small, it can be hidden along the trim of a doorway or even up the leg of a coffee table. There is a remote room sensor port on the rear of the unit for easy external connection.


Unfortunately, sometimes products do not work like they are supposed to. We offer a 90 day warranty on manufacturer defects. Some manufacturers make this a very simple and easy process unfortunately others do not. Items must be used in accordance with the manufacturers guidelines to qualify for warranty replacement. Please be advised that warranty claims for these parts may take up to 4 weeks for processing, and customers must cover shipping.

Shipping Info

This Item Qualifies For Free Shipping With Orders Over $99!

When Will My Order Ship

All orders are typically processed within 24 hours of receiving payment and are shipped from us same day if placed before our shipping cutoff time (Monday - Friday: 1PM, Saturday: 10AM, Sunday: No Shipping), orders placed after our cutoff time are shipped the next morning.

How Does Free Shipping Work?

Most orders over $99 qualify for free shipping! Orders which ship for free are shipped with either USPS or UPS based on our discretion. If you are using a PO box, free shipping orders will always go USPS.

Is Expedited Shipping Available?

We offer both overnight and two day air shipping services for all orders placed within the Continental United States. For information on shipping cut-off times, go to our shipping page.

Do You Ship To Canada?

We ship to Canada! We estimate USPS to take 4-10 days once receiving your package from us. We do not offer expedited shipping of any kind to Canada. Please allow an extra 2-5 days for all shipments to Canada. Free shipping is not available to Canada.

Do You Ship To Alaska Or Hawii?

We ship to both Alaska and Hawaii! We do not offer next day or two day shipping to Alaska or Hawaii. Free shipping is not available to Alaska or Hawaii.

Do You Ship Outside The US Or Canada?

Unfortunately, at this time we do not offer international shipping other than to Canada.

If you wish to calculate shipping for an item which does not qualify for free shipping, or if you would like the cost to expedite your order, please do the following. Add the item you want to order to your cart and click here to be taken to the cart page where you can enter your country, state / province, and zip code for an estimate.

Shipping Time Estimations

For information on shipping time estimations, see either the Shipping Information & Transit Times on the cart page, or go to our shipping page.

Read More About Our Shipping Information

Customer Reviews

Based on 8 reviews

very well happy


Harman Room Temperature Sensor, 3-20-00906


Fast, easy and decent prices. Very happy with my order.

room temp sensor

It was exactly what we were looking for and it worked perfectly in our Harmon pellet stove.

Parts were what we wanted

it is great. Thanks for the quick delivery


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