The WirthCo 20090 Battery Doctor Battery Isolator is a fully automatic electronic battery controller designed to manage dual battery systems in 12V applications. Built with advanced electronic switching technology, it allows efficient charging of both batteries while protecting the starting battery from discharge.
Key Specifications
Manufacturer: WirthCo Manufacturer Part Number: 20090 Series: Battery Doctor Application: 12 Volt battery charging and isolating systems Amperage: 100 Amp Control Type: Electronic automatic controller Includes Solenoid: No Includes Switches: Yes Includes Fuse: Yes Includes Mounting Bracket: Yes Condition: New
Features & Benefits
Fully automatic dual battery controller for seamless operation
Charges two batteries from a single alternator
Keeps starting battery isolated to prevent discharge
Priority charging for starting battery
Manual override/reset button enables parallel connection for jump starting
Electronic switching technology for efficient and reliable performance
Over-current and surge protection for modern vehicle electronics
Water-resistant (IP62 rated) for marine and outdoor use
Compact, lightweight design for easy installation
Automatically charges auxiliary battery as needed
Backed by a limited 1-year warranty
Product Description
The WirthCo 20090 Battery Doctor Battery Isolator is an advanced solution for maintaining and managing dual battery systems in RVs, marine applications, and work vehicles. Its state-of-the-art electronic control system ensures both batteries are charged efficiently while safeguarding the primary battery used for engine starting.
Unlike traditional isolators, this unit offers a manual override function, allowing both batteries to be connected in parallel for emergency starting situations. The compact and water-resistant design makes it suitable for demanding environments where reliability is critical.
Designed for ease of installation and dependable performance, the Battery Doctor isolator is ideal for users requiring efficient power management and battery protection in a single, integrated unit.
Important Notice
This electrical component is non-returnable. Please confirm compatibility with your system before purchasing.
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Refund Policy
UsedRVParts.ca (“Company”, “we”, “us”, or “our”) supplies specialty new and used RV parts. Due to the nature of RV parts, including fitment variability, installation sensitivity, and industry-standard return and restocking practices, the following policy applies to all purchases.
By placing an order, you (“Customer”, “Buyer”) acknowledge and agree to these terms.
1. Final Sale Categories – Non-Returnable Items
The following items are final sale and are not eligible for return, refund, or exchange:
Special orders
Out-of-stock items
Obsolete or discontinued parts
Custom-made or custom-requested products
Batteries
Chemicals, sealants, sprays, and aerosol products
All purchases in these categories are final once payment is processed. Customers are responsible for confirming compatibility prior to purchase.
2. Electronic Components – Final Sale
All electronic components (including circuit boards):
Are sold final sale, as-is
Are not eligible for return or refund
Must be diagnosed and handled through manufacturer processes if issues arise
Important: Due to the high rate of damage from improper installation and part swapping, all electronic items are tested and documented prior to shipment.
3. Returns for New Parts
We accept returns on eligible new, unused parts under the following conditions:
Return Requirements
Request submitted within 30 days of confirmed delivery
Item is unused, uninstalled, and in resalable condition
Original packaging, manuals, and components included
Item passes inspection upon return
Fees & Conditions
These restocking fees and return conditions reflect standard practices within the RV parts and specialty components industry, where many items cannot be resold once handled or installed.
Minimum 20% restocking fee
Return shipping is the responsibility of the Buyer
Original shipping charges are non-refundable
Refunds are issued to the original payment method within 7 business days after inspection and approval.
Non-Returnable New Items (No Exceptions)
Installed products
Generators that have been used or had oil added
4. Used RV Parts – Final Sale
All used parts are sold:
AS-IS – NO RETURNS – NO REFUNDS – NO WARRANTIES
Each used item is inspected and tested prior to shipment to ensure it is in working condition at the time of sale. However, due to the nature of used components:
Fitment and compatibility are the Buyer’s responsibility
Installation outcome is the Buyer’s responsibility
No exceptions will be made for:
Incorrect orders
Installation issues
Buyer error
5. Defective Products & Manufacturer Warranty
UsedRVParts.ca is not the manufacturer and does not provide product warranties.
If a product is believed to be defective:
It must be diagnosed by a qualified professional installer
All warranty claims must be submitted directly to the manufacturer
We will assist by providing:
Manufacturer contact information
Original invoice
We do not:
Approve warranty claims
Replace products under manufacturer warranty
Accept returns for manufacturer defects
6. Installed Products
Any product that has been installed is considered used and is not eligible for return or refund.
7. Shipping, Delivery & Risk
Responsibility for return shipping and carrier damage claims is consistent with standard practices across the RV parts and e-commerce industry, where carriers assume responsibility once shipments are accepted.
Risk transfers to the Buyer once the order is accepted by the carrier
Delivery timelines are estimates and not guaranteed
Customers are responsible for:
Providing accurate shipping details
Monitoring tracking and delivery
8. Shipping Damage & Claims
All items are packaged to industry standards.
Upon delivery, the Buyer must:
Inspect all packages immediately
Note any damage with the carrier
Report issues within 5 business days
For damage claims:
Photos of packaging and product are required
Claims must be filed directly with the carrier
We will assist in the claims process where applicable but are not responsible for claim outcomes.
9. Undeliverable & Refused Shipments
The following situations will incur a minimum 15% restocking fee:
Incorrect or incomplete address
Unclaimed shipments
Refused deliveries
Mid-transit cancellations
Additional conditions:
Original shipping is non-refundable
Re-shipping requires new payment
10. International Orders
The Buyer is responsible for all:
Customs duties
Import taxes
Brokerage fees
Failure to pay these charges may result in:
Return shipment at Buyer’s expense
Applicable restocking fees
11. Payment Verification & Fraud Prevention
All orders are subject to:
Payment authorization and verification
Fraud screening and risk assessment
We reserve the right to:
Cancel or refuse any order
Request identity verification
Hold orders pending review
12. Chargebacks & Disputes
By completing a purchase, the Buyer agrees to contact us first to resolve any issues.
We reserve the right to dispute chargebacks and provide supporting documentation, including:
Proof of delivery
Order confirmation and policy agreement
Product documentation and communication records
13. Limitation of Liability
To the maximum extent permitted by law:
Liability is limited to the purchase price of the product
We are not responsible for:
Installation or labor costs
Property damage
Loss of income or downtime
14. Indemnification
The Buyer agrees to indemnify and hold harmless UsedRVParts.ca from claims arising from:
Installation or use of products
Misuse or modification
Third-party damages
15. Agreement to Terms
By placing an order, you confirm:
Acceptance of this policy
Understanding that certain items are final sale
Agreement to these terms to the fullest extent permitted by law
16. Governing Law
This policy is governed by the laws of British Columbia, Canada. Any disputes will be resolved in Kelowna, BC.
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