So your ASIC miner is down. Maybe a hashboard stopped hashing, a fan died, or the whole unit refuses to boot. You have done the troubleshooting, tried the firmware flash, reseated every connector — and it is still broken. Now what?
At D-Central Technologies, we have been repairing ASIC miners since 2016. Thousands of machines have come through our repair facility in Laval, Quebec — from beat-up S9s pulled out of shipping containers to brand-new S21s with factory defects. We know the process can feel opaque when you are shipping expensive equipment to someone you have never met. This guide is our commitment to transparency: here is exactly what happens when you send your miner to D-Central for repair, from first contact to the moment your machine is hashing again.
The D-Central Repair Process: 8 Steps
Step 1: Contact Us
Every repair starts with a conversation. Reach out to us through any of these channels:
- Repair request form: d-central.tech/asic-repair — our preferred method, as it captures all the details we need upfront
- Email: Send us the details at our contact address
- Contact page: d-central.tech/contact
What to include in your initial message:
- Miner model and version (e.g., “Antminer S19j Pro” or “Whatsminer M30S+”)
- Serial number (found on the sticker on the miner chassis)
- Description of the problem — be as specific as possible. “It does not work” tells us very little. Hashboard 2 shows 0 chips in kernel log, boards 1 and 3 are normal” tells us a lot.
- Any troubleshooting you have already attempted (firmware flash, fan swap, connector reseating, etc.)
- Screenshots or photos if relevant (kernel log screenshots, photos of visible damage, error messages)
- Your return shipping address
We respond to repair inquiries within one business day. If your situation is urgent, note that in your message — we prioritize based on severity and business impact.
Step 2: Ship Your Miner to Us
Once we confirm we can service your model, it is time to ship. Send your miner to:
D-Central Technologies
1325 Rue Bergar
Laval, QC H7L 4Z7
Canada
Packaging Guidelines (Critical)
Improper packaging is the number one cause of additional damage during shipping. ASIC miners are heavy, dense equipment with fragile components. Follow these guidelines:
| Do | Do Not |
|---|---|
| Use the original packaging if you still have it | Ship in a thin cardboard box with no padding |
| Use a double-walled corrugated box rated for the weight | Use newspaper or packing peanuts (they shift and settle) |
| Wrap the miner in anti-static bubble wrap | Let the miner move inside the box — shake test it |
| Use at least 3 inches of foam or dense bubble wrap on all sides | Stack multiple miners in one box without individual wrapping |
| Seal all seams with packing tape | Ship with fans installed if they are loose or damaged |
| Include a printed note with your name, email, and issue description | Assume we will remember your email — always include a note in the box |
What to Include in the Box
- The miner unit (with hashboards installed)
- A printed note with your name, contact email, phone number, and a description of the problem
- The control board (leave it connected unless you are sending a hashboard only)
- Fans (leave installed unless they are the problem — in that case, bag and label them separately)
What NOT to Send
- Power supplies (PSU): Unless the PSU itself is what needs repair, do not send it. It adds weight, cost, and shipping risk. We have test PSUs for every model.
- Power cables: We do not need your power cord. Keep it.
- Network cables: Not needed.
- Mounting brackets or racks: Remove any custom mounting hardware before shipping.
- Accessories unrelated to the repair: Shrouds, duct adapters, custom enclosures — keep them at home unless they are part of the problem.
Shipping Tips
- Insure your shipment. ASIC miners are valuable. A replacement S21 costs thousands of dollars. Insure for the full replacement value.
- Use a trackable service. We recommend Canada Post Xpresspost, UPS, or FedEx with tracking. Do not use untracked services.
- Declare the correct value for customs. If you are shipping from outside Canada, accurately declare the item and value on customs forms. Mark as “electronic equipment for repair and return” to avoid unnecessary duties.
- Ship on Monday-Wednesday. This avoids your miner sitting in a warehouse over the weekend.
- Send us the tracking number so we can watch for the arrival and prioritize your unit when it lands.
Step 3: We Receive and Log Your Miner
When your miner arrives at our facility, we:
- Log the unit into our repair tracking system with your contact information, model details, and reported issue
- Photograph the miner’s condition on arrival (this protects both of us in case of shipping damage)
- Assign a repair ticket number — this is your reference for all future communication about this repair
- Send you a confirmation email with your ticket number and estimated diagnosis timeline
Step 4: Diagnosis (2-3 Business Days)
This is where our experience matters most. Our technicians run a comprehensive diagnostic process:
- Visual inspection: We examine the entire unit under magnification for visible damage — burned components, corroded connectors, cracked solder joints, swollen capacitors, damaged traces
- Power-on test: We connect the miner to our test bench with calibrated power supplies and monitor the boot sequence, kernel log output, and initial performance
- Kernel log analysis: The kernel log tells us exactly which components are communicating (or not), which chips respond, temperature readings, fan speeds, and error codes
- Electrical testing: Using multimeters, oscilloscopes, and thermal imaging, we test voltage rails, resistance paths, and thermal profiles to isolate the fault
- Component-level fault isolation: Once we narrow down the failure area, we identify the specific component or components that need replacement or rework
Diagnosis typically takes 2-3 business days from the time we receive your miner. Complex cases (intermittent failures, multiple faults, water damage) may take longer. We will keep you updated.
Step 5: You Receive a Quote
After diagnosis, we send you a detailed repair quote that includes:
- What we found: A plain-language explanation of the failure, not just technical jargon
- What needs to be done: The specific repairs required
- Parts needed: Any replacement components and their cost
- Labor estimate: The repair labor cost
- Total cost: All-in price with no hidden fees
- Estimated timeline: How long the repair will take once approved
- Our recommendation: If we believe the repair cost approaches or exceeds the value of the unit, we will tell you honestly. We would rather earn your trust than charge you for a repair that does not make economic sense.
No surprises. We do not start any repair work until you explicitly approve the quote. If you decide not to proceed, we return your miner — you only pay a diagnostic fee and return shipping.
Step 6: You Approve, We Repair (5-10 Business Days)
Once you approve the quote, our technicians get to work. Repair timelines vary by complexity:
| Repair Type | Typical Timeline |
|---|---|
| Fan replacement, connector repair | 1-2 business days |
| Control board repair (firmware, NAND, Ethernet) | 2-3 business days |
| Hashboard chip replacement (BGA rework) | 3-7 business days |
| Multiple hashboard repairs | 5-10 business days |
| Complex multi-fault repairs | 7-10 business days |
Timelines can extend if replacement parts need to be sourced. We maintain inventory of the most common components (ASIC chips, voltage regulators, connectors, fans, capacitors) for popular models, but rare or new-generation parts sometimes have lead times. If a delay occurs, we notify you immediately with an updated timeline.
Step 7: Burn-In Testing (48 Hours)
This is the step that separates a professional repair from a quick fix. After completing the repair, we do not just power it on, see it hash, and call it done. We run a full 48-hour burn-in test:
- Full hashrate verification: We confirm the miner reaches its rated hashrate across all hashboards
- Stability monitoring: The miner runs continuously for 48 hours while we monitor for hashrate drops, chip dropouts, temperature spikes, or error messages
- Temperature profiling: We verify all chips are within normal thermal range under sustained load
- Fan speed verification: All fans are confirmed running at correct speeds with no abnormal noise
- Power consumption check: We verify the miner draws expected wattage, confirming no hidden faults
If anything fails during burn-in, we go back to the bench. The 48-hour test catches intermittent failures that a quick power-on test would miss. When your miner leaves our facility, it has been proven stable under sustained load.
Step 8: We Ship It Back
After passing burn-in testing:
- We carefully package your miner using proper anti-static materials and padding
- We send you a shipping notification with the tracking number and carrier details
- We include a repair summary document detailing what was diagnosed, what was repaired, and any recommendations for ongoing maintenance
Return shipping is at the customer’s expense unless otherwise arranged. We use insured, tracked shipping for all returns.
Timeline Summary: End to End
| Phase | Duration |
|---|---|
| Initial contact and response | Within 1 business day |
| Shipping to D-Central | Depends on your location (typically 2-7 days) |
| Receiving and logging | Same day or next business day |
| Diagnosis | 2-3 business days |
| Quote approval | Depends on you |
| Repair | 1-10 business days (varies by complexity) |
| Burn-in testing | 48 hours (2 business days) |
| Return shipping | Depends on your location (typically 2-7 days) |
Typical total turnaround: 2-4 weeks from the time you ship to the time you receive your repaired miner back. Simple repairs (fan, firmware) are faster. Complex hashboard repairs with parts sourcing take longer.
What Models Do We Repair?
D-Central repairs all major ASIC miner brands and models, including:
- Bitmain Antminer: S9, S15, T15, S17/T17 series, S19/T19 series (all variants), S21, L3+, L7, D7, DR5
- MicroBT Whatsminer: M20, M21, M30/M30S series, M31, M32, M50 series, M60 series
- Canaan Avalon: AvalonMiner 1047, 1146 Pro, 1166 Pro, 1246
- Innosilicon: T1, T2, T2T, T3, A4+, A10
We have model-specific repair pages with detailed information about common issues for each model. If your model is not listed above, contact us — we can likely still help.
Shipping from Outside Canada
We serve customers across North America and internationally. If you are shipping from outside Canada:
- Customs declaration: Mark the shipment as “Electronic equipment sent for repair and return.” Declare the actual value for insurance purposes.
- Duties and taxes: Equipment sent for repair and returning to its country of origin can often be imported duty-free under temporary import provisions. Check your country’s customs regulations.
- US customers: UPS and FedEx offer the most reliable cross-border service between the US and Canada. USPS to Canada Post also works but can be slower.
- International customers: DHL and FedEx International are recommended for overseas shipments. Factor in 5-10 business days for international shipping each way.
Warranty on Repairs
All repairs performed by D-Central come with a warranty on the specific work performed. The warranty covers the repaired component against the same failure. Normal wear, new damage, power surges, and issues unrelated to the original repair are not covered. Specific warranty terms are included with your repair quote.
Frequently Asked Questions
How much does ASIC miner repair cost?
Costs vary widely depending on the model, the fault, and the components needed. Simple repairs like fan replacement or connector rework are significantly less expensive than hashboard chip replacement. We always provide a detailed quote after diagnosis, and you are never charged for repair work you have not approved. Contact us for a preliminary estimate based on your symptoms.
Do I need to send the entire miner, or just the broken part?
If you know exactly which component is faulty (e.g., a specific hashboard), you can send just that part. However, if you are unsure, we recommend sending the complete miner so we can run full system diagnostics. Some issues that appear to be hashboard problems are actually caused by the control board, power delivery, or cable connections — and those can only be diagnosed with the full unit.
What if you determine the miner is not worth repairing?
We will tell you honestly. If the repair cost exceeds the value of the unit or is close to it, we recommend against the repair and explain your options. You can have the unit returned (diagnostic fee + return shipping applies) or, in some cases, we can offer to purchase the unit for parts. We would rather give you straight advice than charge for a repair that does not make financial sense.
Can I track the status of my repair?
Yes. When your miner is logged, you receive a ticket number. You can email us at any time with your ticket number to get a status update. We also proactively notify you at each major milestone: received, diagnosed, quote sent, repair complete, shipped.
What payment methods do you accept for repairs?
We accept Bitcoin (preferred — we are Bitcoin Mining Hackers, after all), credit cards, Interac e-Transfer (for Canadian customers), and bank wire for larger amounts. Payment is due after repair approval and before return shipping.
I already tried replacing a component and it did not fix the problem. Can you still help?
Absolutely. Many of the miners we receive have already been partially troubleshot by the owner. Just be upfront about what you have tried and any components you have swapped or modified. This helps our technicians avoid duplicating work and gets to the real root cause faster. Even if a previous repair attempt caused additional damage, we have seen it all and can usually still help.
Do you offer rush or priority repair service?
We handle repairs on a first-come, first-served basis, but we understand that downtime costs money. If you have an urgent situation, let us know in your initial contact. We will do our best to prioritize your repair within our capacity. Large fleet operators and repeat customers may also qualify for priority handling — ask us about it.
My miner is still under Bitmain/MicroBT warranty. Should I send it to you instead?
If your miner is under manufacturer warranty, we recommend contacting the manufacturer first. However, many miners find that manufacturer warranty service involves long wait times, international shipping, and communication difficulties. If you decide manufacturer warranty is not practical, we are here as an alternative. Note that opening the miner or having it repaired by a third party may void the manufacturer warranty.
Ready to Get Your Miner Back Online?
Every day your miner sits idle is hashrate lost. Whether you have got a dead hashboard, a mysterious error code, or a machine that simply will not boot, we have the expertise and equipment to diagnose and fix it.
D-Central Technologies has been repairing ASIC miners since 2016 from our facility in Laval, Quebec. We are the Bitcoin Mining Hackers — we built our reputation on understanding these machines at the deepest level.
Related Resources
- D-Central ASIC Repair Services — All models, all manufacturers
- Antminer Error Code Guide — Diagnose your Antminer before shipping
- Whatsminer Error Code Reference — Diagnose your Whatsminer before shipping
- Kernel Log Reading Guide — Understand what your miner is telling you
- Multimeter Guide for ASIC Repair — Basic electrical diagnostics you can do at home