AMETEK Lamb 117939 Vacuum Motor for MD Central Vacuum – Part# 199R

AMETEK Lamb 117939 Vacuum Motor for MD Central Vacuum – Part# 199R

Available: In Stock
$207.44
Image
  • Order within

Quick Summary

This replacement vacuum motor is the AMETEK Lamb 117939 used in select MD central vacuum power units. It is a new motor, not rebuilt, and is listed for MD M850 and M850H 120V models.

Available from Ace Vacuums, with help matching parts to your MD central vacuum system at our Fairfax and Leesburg, VA showrooms.

Quick Highlights

  • AMETEK Lamb 117939 motor
  • New motor, not rebuilt
  • 3-stage motor design
  • 110-120 volt, 50-60 hertz
  • Listed for MD M850 and M850H (120V)
  • Part number 199R

Product Overview

The 117939 Vacuum Motor is a replacement motor for select MD central vacuum power units. This AMETEK Lamb motor is listed for MD M850 (120V) and MD M850H (120V) models and may also be marked 7939 or 11-7939.

Specifications provided for this motor include a 3-stage design, 5.7 inch bottom diameter, 8 inch height, 3-1/2 inch bolt height, 138.6 inch waterlift, 101.2 CFM, 458 air watts, and 13.6 amps. It only replaces the 117939 motor.


Key Features

  • Direct replacement: This motor only replaces the AMETEK Lamb 117939 motor.
  • Fits select MD models: It is listed for MD M850 (120V) and MD M850H (120V) power units.
  • New motor: This is a brand new motor, not a rebuilt unit.
  • Performance specs provided: The listed specifications include 138.6 inch waterlift, 101.2 CFM, and 458 air watts.
  • Common identification numbers: The motor may also be labeled 7939 or 11-7939.
  • Brushes can be replaced: The 117939 motor uses carbon motor brushes that can be replaced.

MD Compatibility

This part is listed as the match for these MD central vacuum power units:

  • MD M850 (120V)
  • MD M850H (120V)

Check the model number on your power unit label before ordering. Our team can confirm the match if you are unsure.


Technical Specifications

Specification Details
Brand AMETEK Lamb
Motor number 117939
Part number 199R
Fan stages 3
Bottom diameter 5.7 in
Voltage 110-120
Hertz 50-60
Height 8 in
Bolt height 3-1/2 in
Waterlift 138.6 in
CFM 101.2
Air watts 458
Amps 13.6
Fits MD models MD M850 (120V), MD M850H (120V)
Compatibility note Includes AirMaster, Modern Day and SilentMaster
Authorized Dealer Ace Vacuums

Best For

  • Replacing a worn 117939 motor in an MD central vacuum
  • MD M850 (120V) and M850H (120V) units
  • Matching a motor labeled 117939, 7939, or 11-7939
  • Restoring a unit with motor-related shutdown or sparking symptoms

Not Ideal For

  • Not for replacing other motor numbers
  • Not for MD models outside the listed fit without confirming compatibility
  • Mini breaker or relay issues may need separate diagnosis or parts

Why Buy from Ace Vacuums

When you purchase from Ace Vacuums, you receive:

  • Central vacuum parts matched to your MD system
  • Help choosing the right hose, tools and inlet parts
  • Knowledgeable support before and after the sale
  • Shipping or pickup at our Fairfax and Leesburg showrooms

Available Online & In-Store

The AMETEK Lamb 117939 Vacuum Motor for MD Central Vacuum is available online and in-store through Ace Vacuums.

Visit Our Showrooms

  • Fairfax, VA: 11110 Main St, Fairfax, VA 22030
  • Leesburg, VA: 300 Fort Evans Rd NE, Leesburg, VA 20176

Call 703-997-9292 (ext. 1 Fairfax, ext. 2 Leesburg).


Quick Summary

This replacement vacuum motor is the AMETEK Lamb 117939 used in select MD central vacuum power units. It is a new motor, not rebuilt, and is listed for MD M850 and M850H 120V models.

Available from Ace Vacuums, with help matching parts to your MD central vacuum system at our Fairfax and Leesburg, VA showrooms.

Quick Highlights

  • AMETEK Lamb 117939 motor
  • New motor, not rebuilt
  • 3-stage motor design
  • 110-120 volt, 50-60 hertz
  • Listed for MD M850 and M850H (120V)
  • Part number 199R

Product Overview

The 117939 Vacuum Motor is a replacement motor for select MD central vacuum power units. This AMETEK Lamb motor is listed for MD M850 (120V) and MD M850H (120V) models and may also be marked 7939 or 11-7939.

Specifications provided for this motor include a 3-stage design, 5.7 inch bottom diameter, 8 inch height, 3-1/2 inch bolt height, 138.6 inch waterlift, 101.2 CFM, 458 air watts, and 13.6 amps. It only replaces the 117939 motor.


Key Features

  • Direct replacement: This motor only replaces the AMETEK Lamb 117939 motor.
  • Fits select MD models: It is listed for MD M850 (120V) and MD M850H (120V) power units.
  • New motor: This is a brand new motor, not a rebuilt unit.
  • Performance specs provided: The listed specifications include 138.6 inch waterlift, 101.2 CFM, and 458 air watts.
  • Common identification numbers: The motor may also be labeled 7939 or 11-7939.
  • Brushes can be replaced: The 117939 motor uses carbon motor brushes that can be replaced.

MD Compatibility

This part is listed as the match for these MD central vacuum power units:

  • MD M850 (120V)
  • MD M850H (120V)

Check the model number on your power unit label before ordering. Our team can confirm the match if you are unsure.


Technical Specifications

Specification Details
Brand AMETEK Lamb
Motor number 117939
Part number 199R
Fan stages 3
Bottom diameter 5.7 in
Voltage 110-120
Hertz 50-60
Height 8 in
Bolt height 3-1/2 in
Waterlift 138.6 in
CFM 101.2
Air watts 458
Amps 13.6
Fits MD models MD M850 (120V), MD M850H (120V)
Compatibility note Includes AirMaster, Modern Day and SilentMaster
Authorized Dealer Ace Vacuums

Best For

  • Replacing a worn 117939 motor in an MD central vacuum
  • MD M850 (120V) and M850H (120V) units
  • Matching a motor labeled 117939, 7939, or 11-7939
  • Restoring a unit with motor-related shutdown or sparking symptoms

Not Ideal For

  • Not for replacing other motor numbers
  • Not for MD models outside the listed fit without confirming compatibility
  • Mini breaker or relay issues may need separate diagnosis or parts

Why Buy from Ace Vacuums

When you purchase from Ace Vacuums, you receive:

  • Central vacuum parts matched to your MD system
  • Help choosing the right hose, tools and inlet parts
  • Knowledgeable support before and after the sale
  • Shipping or pickup at our Fairfax and Leesburg showrooms

Available Online & In-Store

The AMETEK Lamb 117939 Vacuum Motor for MD Central Vacuum is available online and in-store through Ace Vacuums.

Visit Our Showrooms

  • Fairfax, VA: 11110 Main St, Fairfax, VA 22030
  • Leesburg, VA: 300 Fort Evans Rd NE, Leesburg, VA 20176

Call 703-997-9292 (ext. 1 Fairfax, ext. 2 Leesburg).


Frequently Asked Questions

Which MD central vacuum models does this motor fit?

This motor is listed for MD M850 (120V) and MD M850H (120V).

Is this a rebuilt motor?

No. It is a brand new motor, not rebuilt.

What motor does this replace?

It only replaces the 117939 motor.

Can this motor have other numbers on it?

Yes. It may say 7939 or 11-7939.

What are the basic electrical specs?

The listed specs are 110-120 volts, 50-60 hertz, and 13.6 amps.

What are signs that the motor may need replacement?

The record lists signs such as a mini breaker popping, electrical smell, excessive blue sparks from the motor top, a click with no startup, shutting down on its own and working later, or reaching its expected life.

Can the brushes be replaced on this motor?

Yes. The 117939 motor has carbon motor brushes that can be replaced.

How do I confirm MD central vacuum compatibility?

If you have an MD M850 (120V) or MD M850H (120V), this is the listed motor. If your model is different, confirm the exact power unit model and motor number before ordering.

Visit Our Showrooms

Check real-time traffic and travel time from your location in VA, DC, or MD.

📍 AceVacuums Fairfax (DMV Hub)

Address: 11110 Main St, Fairfax, VA 22030
Landmark: Opposite Havertys Furniture Store
Best for: Bethesda, Potomac, Arlington, NW Washington D.C.

Get Real-Time Traffic & Directions

📍 AceVacuums Leesburg

Address: 300 Fort Evans Rd NE, Suite 104, Leesburg, VA 20176
Landmark: Next to Home Depot in Leesburg
Best for: Ashburn, Sterling, Frederick MD, Loudoun County

Get Real-Time Traffic & Directions

Shipping, Return & Refund Policy

Shipping Policy

In-stock merchandise generally ships from our Leesburg, Virginia location within 3–5 business days. Processing time is separate from carrier transit time and is not a guaranteed delivery date. Weekends and holidays can affect timing. Special-order, backordered or unavailable items may take longer; contact us to confirm timing before purchase when a deadline matters.

Shipping options and charges are shown at checkout. After dispatch, follow the carrier's tracking updates. Weather, carrier delays, order verification and inventory confirmation may affect delivery. Inspect packages promptly and retain packaging if there is damage or an incorrect or missing item.

Returns and refunds

Eligible unused items have a 30-calendar-day return request window for refunds or exchanges, measured from delivery or in-store purchase. Return authorization is required. Final-sale exclusions, the 15% restocking fee for change-of-mind returns and shipping responsibilities are explained in our Return and Refund Policy. That policy is the governing source for return eligibility and fees.

For shipping or return help, email sales@acevacuums.com or call 703-997-9292.


30-Day Returns, Refunds and Exchanges

Updated September 27, 2026. Request a return for an eligible unused item within 30 calendar days of delivery (or purchase for items collected in store). Eligible returns may be refunded to the original payment method or exchanged, subject to availability. The same 30-day request window applies to both refunds and exchanges; there is no separate seven-day or 15-day refund deadline.

Eligibility and authorization

Items must be unused, clean, complete and in their original packaging with all accessories, manuals and proof of purchase. Contact sales@acevacuums.com or 703-997-9292 before sending anything back. Include your order number, item and reason for return. We will confirm eligibility, charges and return instructions. Unapproved or cash-on-delivery returns are not accepted.

Fees and shipping

For an approved change-of-mind return, a 15% restocking fee applies to the returned merchandise price. Original shipping charges are not refundable and the customer pays return shipping. These charges do not apply to an approved return caused by our shipping error or a damaged/defective item claim. Contact us first so we can arrange the appropriate remedy and shipping instructions. Do not assume a prepaid label is included.

Final-sale and excluded items

Air purifiers; discounted, clearance, trade-in, holiday-sale and price-matched purchases; gift cards; custom or special-order products; electrical parts; used or installed items; opened cleaning solutions; and used bags, filters, belts or other consumables are not eligible for change-of-mind returns. Other items clearly marked final sale at purchase are also excluded. An opened box alone does not disqualify an otherwise eligible unused, complete item, but consumables and cleaning solutions must remain unopened.

Damaged, defective, incorrect or missing items; recalls

Inspect your order promptly and contact us as soon as you discover a problem, with your order number and photos where helpful. Keep the packaging. Change-of-mind exclusions and deadlines do not remove applicable defect, warranty, recall or statutory rights. Warranty coverage requires evaluation under the manufacturer's terms; dealer status does not guarantee free repair. Recalled products must follow the manufacturer's recall process.

Refund timing and exchanges

After we receive and inspect the return, we will notify you of approval or the reason it cannot be accepted. Approved refunds are issued to the original payment method within 10 business days of approval; your bank may take additional time to post them. Contact us if more than 15 business days have passed since approval. Exchanges require authorization and replacement availability; any price difference and applicable charges will be explained before processing.

Applicable rights and earlier purchases

This policy applies to online and in-store purchases. We will honor more favorable written return terms provided with an earlier purchase. Applicable consumer rights remain unaffected. Where the European Union 14-day cancellation right applies, customers may cancel or return eligible orders within 14 days of receipt, subject to applicable legal exceptions, without giving a reason.


The DMV’s Trusted Vacuum Service Authority

For 25+ years, Ace Vacuums has filled the gap left by big-box retailers. We provide the expert repairs, warranty support, and genuine OEM parts that Amazon and Walmart simply don't offer. From free estimates to same-day service, we are your local alternative for professional home care solutions.

Expert Repairs

  • • Vacuum Belt & Roller Repair
  • • Motor Service & Replacement
  • • Suction Loss & Clog Removal
  • • HEPA Filter & Bag Replacement
  • • Central Vacuum Installation
  • • Central Vacuum Repair
  • • Free Repair Estimates

Authorized Center

  • • Miele & SEBO Warranty
  • • Dyson & Riccar Specialists
  • • Shark, Bissell & Hoover
  • • Kirby & Oreck Rebuilds
  • • MD & Beam Central Vac
  • • Austin Air & Blueair
  • • Simplicity & Electrolux

Northern Virginia

  • Fairfax: Alexandria, Burke, Reston, Vienna, Herndon, McLean.
  • Loudoun: Ashburn, Leesburg, Sterling, Purcellville, Aldie.
  • Prince William: Woodbridge, Manassas, Gainesville, Bristow.
  • Arlington: Rosslyn, Crystal City, Ballston.

Regional Reach

Conveniently serving Washington D.C. and Maryland (Montgomery & Prince George's Counties). Our showrooms are just 20 minutes from DC and 10 minutes from Tysons Corner.

Hablamos Español — Service in English & Spanish.

Serving Zip Codes: 20147, 20176, 22030, 22031, 20151, 20190, 22102, 22314, 20110, 20148 & surrounding areas. All repairs performed by certified technicians using genuine parts.