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Product title:

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

Product rating:
Product price:
$39.99
Product SKU ! 3-20-6866
Product MPN ! 3-20-6866
Product availability: In Stock
Bullet point features

Frequently Bought Together

Total Price: $62.97

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.



Replacement For Part Numbers:

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

View Compatible Models

UPC: 652174670475

Compatible Models

    Harman

  • Absolute 43
  • Absolute 43-C
  • Absolute 63
  • Accentra 52i
  • Accentra 52i TC
  • Accentra Cast FS
  • Accentra Insert
  • Advance
  • Allure 50
  • Allure 50-CE
  • HF60
  • P35i
  • P35i-C
  • P38
  • P38+
  • P43
  • P43-C
  • P61-A
  • P61-C
  • P61A
  • P68
  • P68-C
  • PB105
  • PC45
  • Pellet Pro II
  • PF100
  • PF120
  • XXV
  • XXV TC

Technical Specs

Normal Position Open
Closed Position .10 WC

Instructions

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

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

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




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 these parts may take up to 4 weeks for processing, and customers must cover shipping.

Shipping Information

This Item Qualifies For Free Shipping With Orders Over $49!

HOLIDAY UPDATE
Due to the upcoming Christmas and New Years holidays, shippers will not be picking up on the dates below. Additionally, packages may take longer to arrive than expected. We appreciate your understanding and patience during this time.

  • USPS: No pickup on Dec 24th, Dec 25th, and Jan 1st.
  • UPS: No pickup on Dec 24th (except NDA and 2nd Day), Dec 25th, Dec 31st (except NDA and 2nd Day), and Jan 1st.
CANADA UPDATE

Due to the ongoing Canada Post postal workers' strike, we are forced to suspend all ordering to Canada. Please be advised that any shipments that did not clear U.S. customs by November 15th will be delayed until Canada Post is fully operational. We appreciate your understanding and patience during this time.

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 $49 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 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 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
Jump back to product information tab navigation

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.



Replacement For Part Numbers:

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

View Compatible Models

UPC: 652174670475

Compatible Models

    Harman

  • Absolute 43
  • Absolute 43-C
  • Absolute 63
  • Accentra 52i
  • Accentra 52i TC
  • Accentra Cast FS
  • Accentra Insert
  • Advance
  • Allure 50
  • Allure 50-CE
  • HF60
  • P35i
  • P35i-C
  • P38
  • P38+
  • P43
  • P43-C
  • P61-A
  • P61-C
  • P61A
  • P68
  • P68-C
  • PB105
  • PC45
  • Pellet Pro II
  • PF100
  • PF120
  • XXV
  • XXV TC

Technical Specs

Normal Position Open
Closed Position .10 WC

Instructions

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

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

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




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 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 $49!

HOLIDAY UPDATE
Due to the upcoming Christmas and New Years holidays, shippers will not be picking up on the dates below. Additionally, packages may take longer to arrive than expected. We appreciate your understanding and patience during this time.

  • USPS: No pickup on Dec 24th, Dec 25th, and Jan 1st.
  • UPS: No pickup on Dec 24th (except NDA and 2nd Day), Dec 25th, Dec 31st (except NDA and 2nd Day), and Jan 1st.
CANADA UPDATE

Due to the ongoing Canada Post postal workers' strike, we are forced to suspend all ordering to Canada. Please be advised that any shipments that did not clear U.S. customs by November 15th will be delayed until Canada Post is fully operational. We appreciate your understanding and patience during this time.

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 $49 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 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 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

Customer Reviews

Based on 12 reviews
100%
(12)
0%
(0)
0%
(0)
0%
(0)
0%
(0)
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

E
Eric F.
Great!

As described!

M
Michael B.
Pressure switch

Great service. The switch arrived 2 days after ordered. Turned out that the switch was not the issue with my Harman stove. The feed auger cover was not reinstalled correctly after I cleaned the stove at the end of the last season. Lesson learned. Thanks. Mike.

123

QUESTIONS & ANSWERS

If your question does not concern this specific product, use our contact form
Ask a Question

  • 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

Customer Reviews

Based on 12 reviews
100%
(12)
0%
(0)
0%
(0)
0%
(0)
0%
(0)
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

E
Eric F.
Great!

As described!

M
Michael B.
Pressure switch

Great service. The switch arrived 2 days after ordered. Turned out that the switch was not the issue with my Harman stove. The feed auger cover was not reinstalled correctly after I cleaned the stove at the end of the last season. Lesson learned. Thanks. Mike.

123
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