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Reliance Water Systems 4.5 gal Inline Pressure Tank
Reliance Water Systems 4.5 gal Inline Pressure Tank
Reliance Water Systems 4.5 gal Inline Pressure Tank
Reliance Water Systems 4.5 gal Inline Pressure Tank
Reliance Water Systems 4.5 gal Inline Pressure Tank
Reliance Water Systems 4.5 gal Inline Pressure Tank

Reliance Water Systems 4.5 gal Inline Pressure Tank

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

Cuts down pump cycling with a 4.5 gallon epoxy-lined steel tank that eases wear on your well system's motor and switch.
Reliance Water Systems MPN PMDI-5
Sold Locally Only

This product isn’t sold on our website — see your local hardware store.

In-Store Exclusive

This one's worth the trip to the store.

This Reliance Water Systems item is one you'll find in stores rather than online — and that's often the better way to buy. In store you get the genuine article, full manufacturer warranty, and real advice from someone who's actually handled it — no counterfeits, no gray-market resellers.

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About Product Overview

A well or pump system that short-cycles wears out fast, and that's exactly what the Inline Press Tank 4.5G from Reliance Water Systems is built to prevent. This steel pressure tank holds a 4.5 gallon capacity, giving your pump a buffer of stored water so it doesn't kick on every time a faucet opens. Less cycling means less strain on the motor and switch, which adds up to a longer service life for the whole system.

The tank connects with a 3/4 inch MPT fitting, sized for standard inline installation in home well and pressure systems. Inside, an epoxy lining protects the steel tank from corrosion, a detail that matters given water sits in contact with the tank wall constantly. It's rated to handle water up to 120°F, covering typical residential well water temperatures. Compact at just under 12 inches wide and under 17 inches tall, it fits into tight mechanical rooms or utility closets where space is limited. Made in the USA, it's a solid, no-frills fix for pump systems that are cycling too often.

  • Capacity: 4.5 gallons
  • Material: Steel with epoxy lining for corrosion resistance
  • Connection: 3/4 inch MPT (male)
  • Maximum temperature: 120°F
  • Dimensions: 11.75 x 11.5 x 16.8 inches
  • Weight: 9.77 lbs

The Details Specifications

Ships Ground Travels by ground for safe handling — common for items with a lithium battery, aerosol, or liquid inside. Nothing extra to do on your end; it simply ships by truck instead of by air.
Non-Returnable This product cannot be returned. All sales final.
Brand Reliance Water Systems
Model / MPN PMDI-5
UPC 091194010555
Weight 10 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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