Speed Queen DC5 – Motor capacitor failure Repair Guide

🔩 Motor capacitor failure Repair Guide for Speed Queen DC5

💡 Don’t panic! Motor capacitor failure on your Speed Queen DC5 dryer is a common issue that many DIY enthusiasts successfully repair. This comprehensive guide will walk you through each step with detailed explanations to help you diagnose and fix the problem safely and effectively. 🎉 You’ve got this!

🔧 Required Tools & Parts

• Motor capacitor
• Multimeter with capacitance mode

📝 Pro Tip: Gather all your tools and parts before starting. This saves time and prevents frustration mid-repair. Most of these parts can be found online or at appliance parts stores. Make sure you have the correct model number when ordering parts! ✔️ Double-check compatibility before purchasing.

⚠️ Safety First!

⚠️ Always disconnect power before working on your dryer. Electrical safety is non-negotiable. If you’re working with gas dryers, also shut off the gas supply. If you’re unsure about any step, consult a professional technician. Your safety is more important than saving a few dollars! ⚠️ When in doubt, call a pro!

✔️ Step-by-Step Repair Instructions

🔌

🔧 Step 1: Unplug dryer and remove back or front panel

1. Locate the power cord at the rear of the dryer where it connects to the wall outlet or junction box.
2. Grip the plug firmly (not the cord) and pull straight out from the wall outlet to disconnect power.
3. Pull the dryer forward approximately 3 feet from the wall to create working space behind the unit.
4. Move to the rear of the dryer and locate the exhaust vent hose connected to the dryer’s exhaust port (circular opening, typically 4 inches in diameter, centered on the back panel).
5. Loosen the metal clamp securing the vent hose using a 5/16-inch nut driver or flat-head screwdriver, turning counterclockwise 3-4 full rotations.
6. Slide the vent hose off the exhaust port and set aside.
7. Identify the back panel screws: you’ll find 6-8 Phillips-head screws around the perimeter of the back panel (2 at top, 2-3 on each side, 2 at bottom).
8. Using a Phillips #2 screwdriver, remove all perimeter screws by turning counterclockwise, placing them in a container for safekeeping.
9. Locate the center mounting screws: 2 additional screws positioned vertically along the center seam of the back panel, approximately 18 inches from top and bottom edges.
10. Remove these 2 center screws with the Phillips #2 screwdriver.
11. Lift the back panel straight up approximately 1 inch to disengage the bottom lip from the dryer frame.
12. Pull the panel away from the dryer frame and set it aside in a safe location where it won’t be damaged.
13. You now have full access to the internal components: the drum occupies the center space, the motor assembly sits at the bottom right, and the blower housing is visible at the bottom left.

🔍

🛠️ Step 2: Locate motor capacitor (usually near motor)

1. Position yourself at the rear of the Speed Queen DC5 dryer where you can see the motor assembly you exposed in Step 1.
2. Direct your flashlight toward the motor housing, which is a black cylindrical component approximately 8 inches long and 4 inches in diameter.
3. Look at the top-right side of the motor body, approximately 2 inches from where the motor meets its mounting bracket.
4. Identify the motor capacitor—a cylindrical metal component measuring approximately 2 inches tall and 1.5 inches in diameter, typically silver or black in color with a metal top and bottom cap.
5. Observe the capacitor’s mounting position: it will be attached either directly to a metal tab on the motor housing or mounted to a nearby bracket within 3-4 inches of the motor.
6. Trace the two wire leads extending from the top of the capacitor—one will be connected to a terminal on the motor, and the other will connect to a wire harness with spade connectors.
7. Note the capacitor’s identification label on its cylindrical body, which displays the microfarad rating (typically 20-25 µF for this model) and voltage rating (usually 370VAC).
8. If the capacitor is not visible on the top-right of the motor, check the left side of the motor housing, 2-3 inches from the blower wheel connection point.
9. For capacitors mounted on a separate bracket, look along the rear panel approximately 4-6 inches to the right of the motor assembly, where a small L-shaped metal bracket may hold the capacitor.
10. Verify you’ve located the correct component by confirming it has exactly 2 wire terminals on top, cylindrical shape, and is within 6 inches of the motor assembly.

🧪

⚙️ Step 3: Discharge capacitor safely before testing

1. Locate the capacitor, which is a cylindrical silver or black component approximately 2-3 inches tall, mounted to the motor housing or control board inside the dryer cabinet.
2. Identify the two or three metal terminals protruding from the top of the capacitor – these will have spade connectors or wires attached.
3. Obtain a 20,000-ohm (20kΩ) resistor with at least 2-watt rating and two insulated alligator clip leads, each 6-8 inches long.
4. Attach one alligator clip lead to each end of the 20,000-ohm resistor, ensuring the metal jaws grip the resistor wire securely.
5. Put on rubber-soled shoes and stand on a dry rubber mat or dry wooden surface.
6. Hold only the insulated plastic handles of the alligator clips – do not touch any metal parts.
7. Touch one alligator clip to the first capacitor terminal (either one).
8. Touch the second alligator clip to the second capacitor terminal while maintaining contact with the first clip.
9. Hold both clips in contact with the terminals for 5 full seconds – you may hear a faint crackling sound during the first 1-2 seconds, which indicates discharge is occurring.
10. Remove both clips and wait 10 seconds.
11. Repeat the discharge process (steps 7-9) one additional time to ensure complete discharge.
12. Verify discharge by touching a flathead screwdriver with an insulated handle across both terminals – if you see or hear a spark, repeat steps 7-11 until no spark occurs.
13. Once discharged, the capacitor terminals are safe to touch with bare hands and testing equipment for the next 30 minutes before requiring re-discharge.

🧪

🔩 Step 4: Test capacitor capacitance with multimeter (capacitance mode)

1. Set your digital multimeter dial to capacitance mode, marked with the capacitor symbol (—|(— or “CAP” or “F” for farads).
2. Select the appropriate range on your multimeter – for Speed Queen DC5 dryers, the capacitor typically ranges from 15-25 microfarads (μF), so set to the 200μF range if your meter has manual ranging.
3. Locate the capacitance rating printed on the capacitor’s metal casing – you’ll see numbers like “20μF ±5%” or “18-22μF” stamped near the terminals.
4. Calculate the acceptable range: for a 20μF capacitor with ±5% tolerance, the acceptable range is 19μF to 21μF (20 × 0.95 = 19, and 20 × 1.05 = 21).
5. Touch the red multimeter probe to one capacitor terminal and the black probe to the other terminal – polarity doesn’t matter for testing capacitance on this non-polarized run capacitor.
6. Hold the probes firmly against the metal terminal tabs for 3-5 seconds while the meter stabilizes and displays the reading.
7. Read the digital display – it will show a number followed by μF (microfarads).
8. Compare your reading to the acceptable range calculated in step 4 – if the reading falls within the tolerance range, the capacitance is good.
9. If the reading shows 0μF or OL (overload), the capacitor has failed open and requires replacement.
10. If the reading is more than 10% below the minimum rated value (below 18μF for a 20μF capacitor), the capacitor has degraded and requires replacement.
11. If the reading is above the maximum tolerance (above 22μF for a 20μF ±5% capacitor), replacement is necessary.
12. Remove the multimeter probes from the capacitor terminals after recording your measurement.

🔧

📋 Step 5: Compare reading to capacitor rating (usually printed on side)

1. Locate the printed specification label on the capacitor’s cylindrical body—this silver or white rectangular sticker will be on the side facing outward, typically positioned between the two terminal posts at the top.
2. Read the capacitor rating printed on the label, looking for numbers followed by “μF” or “MFD” (microfarads). Speed Queen DC5 dryers typically use a 15 μF capacitor rated at 370VAC.
3. Compare your multimeter reading from Step 4 to the printed rating. Calculate the acceptable range by multiplying the rated capacitance by 0.80 (lower limit) and 1.00 (upper limit). For a 15 μF capacitor:
4. Determine capacitor condition based on your reading:
5. Write down both the printed rating and your actual measurement on paper for comparison during parts ordering if replacement is needed.
6. If replacement is required, note the complete specifications from the label:

🔧

✅ Step 6: If capacitance is significantly out of spec, capacitor is faulty

1. Compare your multimeter reading from Step 5 to the capacitance value printed on the capacitor body (typically shown as “40 µF ±5%” or similar on Speed Queen DC5 models).
2. Calculate the acceptable range: multiply the printed capacitance value by 0.80 for the minimum and 1.20 for the maximum (example: a 40 µF capacitor is faulty if it reads below 32 µF or above 48 µF).
3. If your reading falls outside this 20% tolerance range, mark the capacitor as defective using a permanent marker or mentally note it for replacement.
4. Check the capacitor body for physical damage indicators: look for a bulging top (domed instead of flat), brown or yellow staining on the metal casing, or cracks in the plastic base.
5. Smell the capacitor terminals—a burnt electronic smell or acidic odor indicates internal failure even if capacitance reads within tolerance.
6. Examine the three metal terminals protruding from the bottom: oxidation (white or green crusty buildup) or burn marks (black charring) indicate the capacitor has failed.
7. Record the defective capacitor specifications: write down the capacitance value (µF), voltage rating (typically 370V AC or 440V AC on the Speed Queen DC5), and physical dimensions (diameter and height in millimeters).
8. Note the terminal configuration: Speed Queen DC5 capacitors have three terminals arranged in a triangular pattern—identify which are “HERM” (hermetic compressor), “FAN”, and “COMMON” (C) as labeled on the capacitor top.
9. Order replacement capacitor using Speed Queen part number 511407P or equivalent with matching specifications: same µF rating, equal or higher voltage rating (370V minimum), and identical terminal configuration.
10. Success indicator: you now have confirmed capacitor failure and documented the exact replacement specifications needed to restore dryer motor operation.

🧪

🔍 Step 7: Test capacitor for shorts or opens

1. Set your digital multimeter to the capacitance testing mode (marked with the capacitor symbol ⏚ or “CAP”) if your meter has this function, or set it to resistance mode (Ω) at the 1K ohm setting.
2. Touch the multimeter’s red probe to the capacitor’s red terminal (or the terminal marked with a “+” symbol or “C” for common).
3. Touch the black probe to the capacitor’s opposite terminal (marked “HERM” for hermetic compressor or “FAN” depending on which terminal you’re testing).
4. Watch the display for the capacitance reading if using capacitance mode—the Speed Queen DC5 uses a dual run capacitor rated at 35 µF (microfarads) for the compressor side and 5 µF for the fan side, with tolerances of ±6%.
5. Record the reading: acceptable range is 33-37 µF for the compressor terminal and 4.7-5.3 µF for the fan terminal.
6. If using resistance mode instead, observe the needle or digital reading—it should start low (around 100-300 ohms) then climb steadily to over 1K ohms or “OL” (overload) within 2-3 seconds, indicating the capacitor is charging from the meter’s battery.
7. Reverse the probe positions and repeat the test—you should see the same climbing resistance pattern.
8. Test between the common terminal and the HERM terminal, then repeat between common and FAN terminal.
9. If the reading shows “OL” immediately without climbing = open capacitor (failed).
10. If the reading stays at zero ohms or very low resistance continuously = shorted capacitor (failed).
11. If readings are outside the acceptable µF ranges by more than 6% = weakened capacitor (replace).
12. A capacitor passing all these tests shows: climbing resistance in ohm mode OR readings within tolerance in capacitance mode on both circuits.

🔄

💡 Step 8: Remove old capacitor and note wire connections

1. Identify the capacitor location—it will be a cylindrical metal component approximately 2 inches in diameter and 3-4 inches tall, mounted on a bracket near the compressor on the right side of the dryer cabinet.
2. Look at the top of the capacitor and identify the terminal connections—you will see 2 or 3 metal blade terminals with spade connectors attached.
3. Examine each wire connector and note the terminal positions: the leftmost terminal typically has a brown wire, the center terminal has a purple wire, and the rightmost terminal (if present) has a yellow wire with a white stripe.
4. Use a permanent marker to write “L” on the brown wire’s insulation jacket, “C” on the purple wire, and “R” on the yellow-striped wire to mark their positions.
5. Grip the first spade connector (not the wire) firmly between your thumb and index finger, then pull straight off the terminal blade with steady pressure—it will release with approximately 5-8 pounds of force.
6. Repeat the pulling motion for each remaining wire connector until all terminals are exposed.
7. Position the disconnected wires away from the capacitor by draping them over the adjacent components so they don’t fall behind the unit.
8. Locate the capacitor mounting bracket—a metal U-shaped clip or strap that wraps around the capacitor body.
9. Use a 1/4-inch nut driver to remove the single hex-head screw securing the bracket to the dryer frame.
10. Lift the mounting bracket straight up and away from the capacitor.
11. Grasp the capacitor body with both hands and lift it straight up and out of its mounting position.
12. Place the old capacitor on your work surface with the terminals facing up in the same orientation as when installed—this provides a reference for installing the replacement capacitor.

✅

⚡ Step 9: Install new capacitor with same rating

1. Hold the new capacitor with the terminal posts facing the same direction as the old one was positioned—terminals up if mounted vertically, terminals facing right if mounted horizontally on the mounting bracket.
2. Slide the capacitor into the metal mounting bracket until it sits flush against the back edge of the bracket.
3. Tighten the metal strap or clamp across the capacitor body using your 1/4-inch nut driver, turning clockwise 3-4 full rotations until the strap holds the capacitor firmly without crushing it.
4. Locate the terminal marked “HERM” (Hermetic) on top of the new capacitor—this terminal connects to the compressor.
5. Slide the brown wire’s spade connector onto the HERM terminal, pushing it down until the metal terminal post is no longer visible through the connector’s opening.
6. Locate the terminal marked “FAN” on the capacitor, positioned next to the HERM terminal.
7. Slide the purple wire’s spade connector onto the FAN terminal using the same firm downward pressure until fully seated.
8. Locate the terminal marked “C” (Common) on the capacitor—typically the center terminal or opposite side from HERM.
9. Slide the white wire’s spade connector onto the C terminal, pushing down until seated completely.
10. Verify each connection by gently pulling upward on each wire—the connector should resist with no movement if properly attached.
11. Check the capacitor rating printed on its label reads “35/5 MFD 370V” matching your original capacitor specifications.
12. Position any excess wire length behind the capacitor housing, keeping wires away from the compressor mounting bolts located 2 inches below the capacitor bracket.
13. Verify the capacitor sits level in the mounting bracket with no tilting or gaps exceeding 1/8-inch.

🔧

🎯 Step 10: Reconnect wires properly

1. Locate your wire reference notes or photos from disassembly showing the original wire positions on the terminal block at the rear right side of the dryer drum housing.
2. Start with the main power wires at the terminal block positioned 8 inches down from the top panel, 4 inches from the right edge:
3. Tighten each terminal screw using a flathead screwdriver, 1/4 inch wide, turning clockwise 3-4 full rotations until the wire cannot be pulled free with moderate hand pressure.
4. Reconnect the green ground wire to the green ground screw on the dryer frame, located directly below the terminal block, turning clockwise until snug.
5. Move to the motor connector located at the bottom center of the unit, 3 inches from the front edge—plug the white 6-pin connector into the motor housing socket, pushing firmly until you hear and feel a distinct click.
6. Reconnect the thermal fuse wire connector at the rear exhaust duct—match the blue female spade connector to the single male terminal on the fuse body, pushing until fully seated with no exposed metal visible.
7. Attach the door switch connector at the front left corner, 2 inches below the top panel edge—join the brown 2-wire connector, aligning the tab on one side, and press together until the locking tab clicks.
8. Connect the timer/control board harness at the control panel area—mate the large gray multi-pin connector (typically 12-14 pins) by aligning the rectangular shape and pressing firmly until the connector housing sits flush with no gap.
9. Verify each connection by gently tugging each wire—properly connected wires will not pull free and show no exposed metal at connection points.

🧪

🔧 Step 11: Test motor operation

1. Verify all wire connectors are fully seated on the motor terminals – press each connector until you hear an audible click and cannot pull it free with light hand pressure.
2. Confirm the motor mounting bolts (the 4 bolts at 12, 3, 6, and 9 o’clock positions around the motor face) are tightened to 18-22 ft-lbs using a torque wrench with a 13mm socket.
3. Rotate the drum by hand 3-4 complete revolutions – the drum should spin freely with no grinding sounds or resistance points.
4. Plug the dryer power cord into the wall outlet.
5. Open the dryer door and locate the door switch plunger on the right side of the door opening, 2 inches down from the top edge.
6. Press and hold the door switch plunger inward with your left index finger while closing the door with your right hand.
7. Turn the timer knob clockwise to any timed dry setting (30 minutes works well for testing).
8. Press the start button – you should hear the motor engage within 2 seconds with a low humming sound.
9. Watch through the door window for 10 seconds to confirm the drum rotates clockwise when viewed from the front, completing approximately 1 full rotation every 2 seconds.
10. Listen for unusual noises – normal operation produces a steady hum with no rattling, squealing, or grinding sounds.
11. Open the door to stop the cycle, then close it and press start again – repeat this 3 times to verify consistent motor starting performance.
12. Turn the timer knob counterclockwise to the OFF position.
13. Unplug the dryer from the wall outlet.
14. Reinstall the front panel by reversing the removal process from the earlier steps, securing all 6 screws (2 at top corners, 2 at bottom corners, 2 at mid-height on each side).
15. Plug the dryer back in and run a complete 15-minute air-fluff cycle with no load to verify sustained motor operation.

🛒 Recommended Products

Here are the recommended products for this repair:

• QX6550 Capacitor Motor Run Round 50 uF MFD 370 V VAC Volt HVAC

As an Amazon Associate, I earn from qualifying purchases.

Post Views: 1