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Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP

Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP
Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP

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Product rating:
Product price:
$49.99

$20.00 less than the OEM

Product SKU ! 3-20-6866-AMP
Product MPN ! 3-20-6866
Product availability: In Stock
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Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMPRelated Product Title Harman Differential Pressure Sensor Vacuum Switch (SRV8320-003) 3-20-6866-OEM
$49.99In stockRelated Product Price: $69.99 In stock
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Frequently Bought Together

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Total for 3 items $86.97

Description

A pressure switch is often referred to as a vacuum switch. This sensor is looking for airflow within the stove to close the circuit to the feed system and the igniter. If your stove is feeding pellets, your pressure switch is ok. For the switch to work properly, the hopper and the front door must be making a tight seal. Almost all of the time, the switch is good but there is an air leak or point of failure somewhere else within the stove. For example, a clogged vent or burnt-out combustion blower motor.

This switch is calibrated to close the ignition and feed circuit at .10 WC PF.

See our Helpful hints and instructions for troubleshooting information.

Vacuum Switch Visual Note: The manufacturer of all OEM and AMP switches has made a design change. The switch received may appear different, but will work the same.


UPC: 652174670475

Replacement For Part Numbers:

  • 3-20-6866
  • 3-20-9301
  • 3-20-3433
  • SRV8320-003

Compatible Models

These are all of the confirmed compatible units for this product. Where To Find Your Make & Model

Technical Specs

Check these against the part you are replacing before ordering. If a dimension does not match, contact us and we will confirm the fit.

Length (in) 3 ¼"
Width (in) 2 ¾"
Height (in) 2 ½"
Normal Position Open
Closed Position .10 WC
Weight 2.25 oz

Wiring and Connectors

Wire, terminals and connectors for the job, in case yours are worn or the ones you have do not reach.

Instructions

Install Instructions For Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP

Instructional Documents

Instructional Videos

Instructional Notes

The switch is located in the rear of the stove. There is a white wire coming from the controller to one side of the switch and there are two light blue wires connected at the terminal on the other side of the switch. These light blue wires run to the igniter and to the feed motor. To change the switch, disconnect the white wire and double blue wires from the switch, disconnect the air tube, replace the switch and then connect the wires and tube back to the switch.

Troubleshooting

Troubleshooting Notes

If the stove is not feeding and you are getting a vacuum error, 99.99% there is usually nothing at all wrong with the switch. The switch is simply sensing an airflow problem and is doing the job it was designed to do. The switch is normally open, which means no power can flow through the switch until the switch senses enough airflow to close the contacts.


The most important thing to know about the pressure switch is:


  • if there is a problem with the switch, the stove's feed system will not dispense pellets because the auger motor is not getting power.
  • unlike most brands, there is no vacuum error code on Harman Pellet Stoves


Common things that cause the switch to remain open are:


  • Excessively Dirty Stove
  • Clogged vent
  • Burnt out of worn out combustion blower
  • Door Gaskets: poor seal on stove door or ash pan door
  • Door Handle: Handle mechanism is broken and the door cannot close properly
  • Bad Hopper Gasket
  • Missing hardware or broken latch on hopper lid
  • Ash pan must be in stove to create proper air flow
  • Combustion motor cover must be installed and seated properly
  • Fines collection box cover must be installed and tightly sealed
  • Units with a hopper lid switch, the switch can fail
  • Units that take the pressure reading from inside the hopper (early versions of the XXV, Accentra and Accentra Insert) can have a broken filter at the end of the vacuum hose or the vacuum hose may have fallen off the end mount
  • Accentra Inserts - Hopper lid can be hinge bound and not seating


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Warranty

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 special parts may take up to 4 weeks for processing, and customers are responsible for return shipping charges.

Shipping Information

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: 12PM, Saturday: 10AM, Sunday: No Shipping), orders placed after our cutoff time are shipped the next morning.
Do You Offer Express Shipping?
Yes! Please note the shipping times are based on business days, weekends and holidays do not count to the delivery date. Please see our expedited ship time schedules here.
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.
Do You Ship To Canada?
We ship to Canada! We estimate USPS to take 4-10 days once receiving your package. Please note, we are unable to track US Postal packages once they cross the US border and cannot guarantee shipping times. All customs fees incurred are the responsibility of the customer and are not included in the total price. 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 Hawaii?
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.
Shipping Time Estimations
For information on shipping time estimations, see the Shipping Information & Transit Times on the shipping page.
Learn More About Our Shipping Information

Questions & Answers

If your question does not concern this part, contact us directly or read our FAQs.

No one has asked about this part yet. Ask us anything specific to it - the wattage, which style or model year it suits, what part numbers it replaces - and we will answer it ourselves.

Every question is read by our team before it appears here, so it will not show up right away - we will email you the answer.

Customer Reviews

Based on 11 reviews
100%
(11)
0%
(0)
0%
(0)
0%
(0)
0%
(0)
W
William T.

AWSOME

S
Stephen H.
Harman XXV parts purchase

I ordered a combustion fan and distribution fan, sensor and a pressure switch. Parts are high quality, most likely same as oem. With the info available on this site I was able to trouble shoot and select the right parts. Parts that fit several models came with instructions on how to wire. Great experience and my Harman XXV is back to nearly silent operation and works properly again.

P
Paul L.
vaccum switch, igniter

Parts were as ordered, fast service

D
Deborah S.
Vacuum Switch, 3-20-6866-AMP

haven't installed it yet but sure it will be fine. shipping was quick.

N
Nathan r.
Direct replacement

Fantastic to have my stove up running again. Fast shipping.

123

Still have a question?

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Contact us 1-508-392-9831
Mon–Sat 9AM–5PM · Sun 10AM–3PM ESTShipping policy · Return policy · FAQs

Customer Reviews

Based on 11 reviews
100%
(11)
0%
(0)
0%
(0)
0%
(0)
0%
(0)
W
William T.

AWSOME

S
Stephen H.
Harman XXV parts purchase

I ordered a combustion fan and distribution fan, sensor and a pressure switch. Parts are high quality, most likely same as oem. With the info available on this site I was able to trouble shoot and select the right parts. Parts that fit several models came with instructions on how to wire. Great experience and my Harman XXV is back to nearly silent operation and works properly again.

P
Paul L.
vaccum switch, igniter

Parts were as ordered, fast service

D
Deborah S.
Vacuum Switch, 3-20-6866-AMP

haven't installed it yet but sure it will be fine. shipping was quick.

N
Nathan r.
Direct replacement

Fantastic to have my stove up running again. Fast shipping.

123