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Product title:

Harman Differential Pressure Sensor Vacuum Switch (SRV8320-003) 3-20-6866-OEM

Product rating:
Product price:
$69.99
Product SKU ! 3-20-6866
Product MPN ! 3-20-6866
Product availability: In Stock
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Frequently Bought Together

Parts other customers added to their cart along with this one. Untick any you do not need, then add the rest together.

Total for 3 items $106.97

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.


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

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

Instructions

Install Instructions For Harman Differential Pressure Sensor Vacuum Switch (SRV8320-003) 3-20-6866-OEM

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.

  1. I can't control the feed. The stove runs wide open,or I have to turn it off.

    You'd want to look at testing the room sensor or ESP sensor, the vacuum switch only opens the feed circuit

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 14 reviews
100%
(14)
0%
(0)
0%
(0)
0%
(0)
0%
(0)
R
Robert W.
Stove parts

The items I recieved was great quality, and the price was way cheaper than my local dealers.
My local dealers told me they couldnt get the parts for 3 weeks.
I paid extra through stove and grill parts and recieved the items the next day.
I will definatly be using yall from now on

R
Robert t.
Pressure Sensor switch

Harmon pellet stove wasn't feeding, changed pressure switch in 10 minutes, stove running perfectly

T
Torre L.
Differential pressure switch

I ordered a pressure switch it got here faster than they said it would! Now we have heat and before it snowed! Thank you Stove and grill parts for less you always have what we need!

J
John G.
Product is perfect

Works and performs perfectly. Thank you for the great part and super fast order fulfillment.

L
Larry L.
Harmon stove part

Part works great

Still have a question?

Call or email us and we will help you find the right part.

Mon–Sat 9AM–5PM · Sun 10AM–3PM ESTShipping policy · Return policy · FAQs

Customer Reviews

Based on 14 reviews
100%
(14)
0%
(0)
0%
(0)
0%
(0)
0%
(0)
R
Robert W.
Stove parts

The items I recieved was great quality, and the price was way cheaper than my local dealers.
My local dealers told me they couldnt get the parts for 3 weeks.
I paid extra through stove and grill parts and recieved the items the next day.
I will definatly be using yall from now on

R
Robert t.
Pressure Sensor switch

Harmon pellet stove wasn't feeding, changed pressure switch in 10 minutes, stove running perfectly

T
Torre L.
Differential pressure switch

I ordered a pressure switch it got here faster than they said it would! Now we have heat and before it snowed! Thank you Stove and grill parts for less you always have what we need!

J
John G.
Product is perfect

Works and performs perfectly. Thank you for the great part and super fast order fulfillment.

L
Larry L.
Harmon stove part

Part works great