Protect your RV water heater from excessive pressure with the Dometic 91604 Water Heater Pressure Relief Valve. This brand new genuine OEM replacement pressure relief valve is factory-set to 150 PSI and is designed to safely relieve excess pressure within the water heater tank, helping protect both the water heater and plumbing system.
Manufactured from durable brass to original equipment specifications, this replacement valve delivers dependable performance, corrosion resistance, and long-lasting durability. Featuring 1/2-inch NPT male and female threaded connections, it is an ideal replacement for worn or malfunctioning pressure relief valves in compatible RV and marine water heater applications.
Features
Genuine Dometic 91604 OEM product
Brand New
Replacement water heater pressure relief valve
Factory-set to relieve pressure at 150 PSI
Durable brass construction
Helps protect the water heater from excessive pressure buildup
Corrosion-resistant for long service life
Precision fit and function
Easy installation
Suitable for RV and marine applications
Specifications
Manufacturer Part Number: 91604
NTP Part Number: 42-0154
Product Type: Water Heater Pressure Relief Valve
Factory Pressure Setting: 150 PSI
Material: Brass
Connection 1: 1/2 Inch NPT Female Threads
Connection 2: 1/2 Inch NPT Male Threads
Gasket Included: No
Quantity: 1
Marine Use: Yes
What's Included
Water Heater Pressure Relief Valve
Compatibility
Compatible with:
RV and marine water heaters using a 1/2-inch NPT, 150 PSI pressure relief valve
Vehicle Notes
Genuine OEM replacement part
Designed to safely relieve excess pressure from the water heater tank
Features 1/2-inch NPT male and female threaded connections
Verify your existing valve specifications before ordering
Important: Confirm your water heater requirements and manufacturer part number 91604 prior to ordering to ensure proper fitment.
Warranty
No Manufacturer Warranty
Estimate shipping
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, shipping logistics, 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
Return 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
Signature confirmation fees are non-refundable where applicable
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
Items damaged after delivery
Orders confirmed delivered by the carrier
Orders confirmed delivered by the carrier, including tracking confirmation, delivery scan, proof of delivery, photo confirmation, GPS confirmation, or signature confirmation where applicable, are considered fulfilled orders.
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
Ensuring a secure delivery location
Being available for signature-required deliveries where applicable
UsedRVParts.ca may require signature confirmation on select shipments at our discretion, including higher-value orders.
Once tracking indicates a shipment has been delivered, including delivery scan, proof of delivery, photo confirmation, GPS confirmation, or signature confirmation where applicable, the order is considered delivered and fulfilled.
UsedRVParts.ca is not responsible for:
Lost or stolen packages after delivery
Porch piracy
Carrier delays
Delivery access issues
Failed delivery attempts
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
Failure to accept signature-required deliveries
Additional conditions:
Original shipping is non-refundable
Return shipping charges may apply
Re-shipping requires new payment
Signature confirmation fees are non-refundable where applicable
Orders returned due to failed delivery attempts or refusal of signature-required shipments will be treated as refused deliveries.
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
Require signature confirmation for high-risk or high-value orders
Delay shipment for additional verification where necessary
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
Carrier tracking records
GPS delivery confirmation
Photo confirmation
Signature confirmation where applicable
Order confirmation and policy agreement
Product documentation and communication records
The Buyer agrees that carrier delivery records and signature confirmation constitute valid proof of fulfillment and delivery.
Claims for packages marked delivered by the carrier may be denied where delivery confirmation exists.
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
Indirect or consequential damages
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
Understanding that risk transfers upon shipment
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.
New & Updated RV Parts Inventory — Check Back Often
We’re always adding new and used RV parts to our inventory, so be sure to check back regularly.
If you don’t see the part you need today, we may still have it in stock—our internal database includes thousands of new RV parts that are not yet listed online.
Text or email us with the product number or model, and we’ll check availability for you right away.
