Heatilator Eco Choice Red Thermister Exhaust Sensing Probe (ESP): 3-20-00844

This version of the ESP is the correct part for any model made after 2008. This updated ESP has red wires, as opposed to the previous probes which could have had black, yellow, or white wires. New Circuit boards are now sensing the condition of the differential pressure switch. (FIG 4) 

Notes for ordering replacement parts:

• If you need a new probe: Order to match your existing probe. Red= #3-20-00844
• Black, White, or Yellow Probe: Order the black Probe.
• If you need a new board: Order using the part numbers included here.
• If installing on a unit with an old probe = Dipswitch #5 “OFF”.
• With new probe= Dipswitch #5 “ON”.

This red ESP is used on all models manufactured after 2008 or any model in the list below with an updated controller:

• 3-20-05886 - Accentra, Accentra Insert, Advance, P43, P61A, P68, and XXV
• 3-20-05887 - PC45 Multi-fuel
• 3-20-05888 - PF100 Pellet Furnace
• 3-20-05890 - P61
• 3-20-06143 - PB105 & HydroFlex 60
• 3-20-05889 - DVC500

Replacement For Part Number:

• 3-20-00844

View Compatible Models

UPC: 652174715022

High Temp Limit

572°F

Install Instructions For Heatilator Eco Choice Red Thermister Exhaust Sensing Probe (ESP): 3-20-00844

You must be careful not to bend an ESP probe if removing it for maintenance purposes. Bending the sheath of the probe will usually ruin the sensor. Likewise, when cleaning your stove, care should be taken to not bend the sensor when cleaning. Do not send brushes or vacuum tools through the stove blindly. Before cleaning your stove for the first time, find the ESP probe and make sure that it is not going to be in the way when cleaning. If it is, remove it from its mount prior to performing work.

Using a 1/4" socket, remove the mounting screw and remove the thermocouple from the stove. Trace the wires back to the control board and unplug the wires.

DIP Setting by Stove Model

Harman Product Update: November 18, 2008 PDF Link

1. If a Red probe is mistakenly used on an old board, the board will read it as an exhaust temperature of around 470° F at room temperature. Therefore, The Combustion and Distribution Blowers will be running immediately.
2. If a Red probe is used on a new board without dip-switch #5 “ON”, the board will read it as an exhaust temperature of around 470° F at room temperature. Therefore, The Combustion and Distribution Blowers will be running immediately.
3. If an old probe is used on new board with dip-switch #5 “ON”, the board will read it as an exhaust temperature of 572°F, and will show a “3 blink” status within 30 seconds. The Combustion and Distribution blowers will run as if in an over temperature condition.
4. If there is insufficient draft, the circuit board will not send power to the feed motor or igniter, and the indicator lights will not be illuminated. However, it will increase the voltage to the combustion blower, in an attempt to improve the draft.
5. If there is insufficient draft, the Combustion blower will not shut off during shut down, Regardless of ESP temperature. This is especially noticed if a door or hopper lid is left open during shut down.
6. On the PC45, (3-20-05887), the five hour shut down timer has been eliminated with the use of a red probe.
7. Make sure the feed motor is properly connected, including the terminal crimps and grounding wire. If not, the software may react as though there is insufficient draft, because the sensing device on the board is receiving a small amount of voltage through the feed motor circuit that should be diverted to ground.

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.

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