Apr 22 , 2026

Everpure H-104 Under-Sink Filter: Installation and Replacement

The Everpure H-104 is the entry point into the Everpure under-sink lineup for a lot of homeowners. It delivers Everpure's signature precoat filtration at a more accessible price than the H-300 and H-1200, in a slightly smaller capacity cartridge that still handles residential drinking water needs cleanly. If you are considering an H-104 system or already have one and need replacement cartridges, this guide covers what you need to know.

What the H-104 Does

The H-104 uses Everpure's proprietary precoat filtration technology, same as the larger H-series cartridges but in a smaller form factor.

Specifically, the H-104 reduces:

  • Chlorine taste and odor
  • Particulates and sediment down to 0.5 microns
  • Dirt, rust, and oxidized iron particles
  • Mold, algae, and microorganisms at the filter level
  • Asbestos

The H-104 has a narrower contaminant reduction profile than the H-300 (which adds cyst reduction and lead reduction in certified configurations). For most municipal water situations where taste and particulate reduction are the primary concerns, the H-104 is enough. For well water, more contaminated municipal water, or installations where lead or cyst reduction matters, the H-300 is the better fit.

Capacity

The H-104 is rated for 750 gallons of filtered water or 6 months of residential use, whichever comes first. Despite the smaller size relative to the H-300, the H-104 rating for total gallons is actually higher because the filter media is configured differently. Most households hit the 6-month time limit before 750 gallons.

Which Systems Use the H-104

The H-104 cartridge is used in a handful of Everpure residential systems including:

  • Everpure H-104 (standalone system)
  • Several OEM drinking water systems built around the H-104 cartridge
  • Some Everpure branded commercial under-counter systems in low-volume applications

If you are looking at a system and trying to confirm whether it uses the H-104, the housing will have the Everpure logo and a model designation that starts with EV. The H-104 cartridge itself is smaller than the H-300, and the housings are sized accordingly. An H-300 cartridge will not fit an H-104 housing, and vice versa.

Installation

First-time installation of an H-104 system requires some plumbing work. Cartridge replacement after the system is installed is much simpler.

New system installation (overview):

First-time H-104 system installation typically involves:

  1. Mounting the filter head under the sink in a stable location
  2. Tapping into the cold water supply line (usually with a saddle valve or a tee fitting)
  3. Running filtered-water tubing to a dedicated filtered-water faucet on the sink
  4. Drilling the sink or countertop for the filtered faucet (if not using an existing hole)
  5. Connecting the tubing to the filtered-water faucet
  6. Flushing the system after installation

Most homeowners either install the system themselves (a 2 to 3 hour project with basic plumbing skills) or have a plumber handle it (1 to 2 hours professional).

Cartridge replacement (ongoing):

Replacing an H-104 cartridge in an already-installed system takes 60 to 90 seconds.

  1. Turn off the water supply at the shutoff valve feeding the filter.
  2. Open the filtered-water faucet to release pressure. Close when flow stops.
  3. Turn the old cartridge a quarter turn counterclockwise. It drops down out of the housing.
  4. Take the new cartridge out of the package. Check the O-ring on top.
  5. Align the new cartridge with the housing head, push up, and turn a quarter turn clockwise until it locks.
  6. Slowly open the water supply. Check for leaks.
  7. Flush the new filter by running the filtered-water faucet for 5 minutes.
  8. Note the replacement date.

When to Replace the H-104

Rated life is 6 months or 750 gallons, whichever comes first. Most residential households hit the 6-month mark.

Signs to replace regardless of time:

  • Flow rate noticeably reduced at the filtered faucet
  • Chlorine taste or off taste returning
  • Cloudiness or visible particles in filtered water
  • Any change in water smell or appearance

Replacing on schedule is not optional. Past the rated life, the filter loses filtration capacity and can start releasing captured contaminants back into the water.

OEM vs Aftermarket

Authentic Everpure H-104 cartridges run $50 to $75. Aftermarket H-104-compatible cartridges run $20 to $40.

The filtration technology in the H-104 is Everpure's proprietary precoat. Aftermarket cartridges labeled as H-104 compatible physically fit the housing but do not necessarily deliver equivalent filtration performance. Many aftermarket versions use standard carbon block media in the H-104 form factor, which filters differently than the precoat design.

For a system chosen specifically because of Everpure's filtration performance, authentic cartridges are usually the right call. The cost difference over a year (two cartridges) is $40 to $70 for filtration performance that matches what the system was designed to deliver.

For buyers where price is the primary factor, quality aftermarket H-104-compatible cartridges provide adequate taste and particulate filtration at lower cost. NSF 42 certification is the minimum to look for.

H-104 vs H-300 vs H-1200

For Everpure buyers deciding between cartridges:

H-104 — Entry-level precoat filtration. 750 gallons, 6 months. Good for municipal water where taste and particulate reduction are primary.

H-300 — Mid-range premium cartridge with cyst reduction and lead reduction in certified configurations. 300 gallons, 6 months. Adds health-contaminant protection over the H-104.

H-1200 — Premium dual-stage cartridge with 1,200 gallon capacity over 12 months. Used in high-end residential installations and small commercial. Highest total capacity in the residential Everpure lineup.

The right cartridge depends on the water being filtered and the installation. Most residential buyers start with the H-104 or H-300 based on local water quality.

Troubleshooting Common Issues

Leak around the cartridge after replacement. The O-ring may be misaligned or the cartridge may not be fully locked. Remove, inspect the O-ring, and reinstall with a complete quarter-turn clockwise.

Slow flow after replacement. First 5 minutes of flow after a new cartridge is normal to be slower and cloudy as air clears and carbon fines flush. If flow stays slow beyond initial flushing, check that the water supply is fully on and the cartridge is correctly seated.

Water tastes off after new cartridge. Flush the filter longer. Carbon fines can affect initial taste. 5 full minutes of flush is the minimum. Some cartridges benefit from longer initial flushing.

Filtered faucet not flowing at all. Confirm water supply valve is open, cartridge is fully locked, and the filtered faucet itself is not clogged or restricted. A bleeder test at the housing head (briefly opening the quick-disconnect) isolates whether the problem is in the cartridge or downstream.

Buying Authentic H-104 Cartridges

Water Filters FAST stocks authentic Everpure H-104 cartridges with same-day shipping on weekday orders placed before 1pm Central. Free shipping over $75. Satisfaction guarantee and 30-day returns.

If you are unsure which cartridge fits your system, the Water Filters FAST support team (855-789-FAST) can identify a system from model number or photo and confirm the right replacement.

Frequently Asked Questions

How long does an Everpure H-104 cartridge last? 750 gallons of filtered water or 6 months, whichever comes first. Most residential installations reach the 6-month time limit before the gallon rating.

What is the difference between the H-104 and H-300 cartridges? The H-300 adds cyst reduction and lead reduction in certified configurations. The H-104 handles taste, odor, particulates, and general sediment reduction. For municipal water where contaminant testing is normal, the H-104 is often sufficient. For water with known lead or cyst concerns, the H-300 is the better choice.

Can I install an H-104 system myself? Yes, with basic plumbing skills and a couple hours. The installation involves tapping into the cold water supply, mounting the filter head, and running tubing to a filtered faucet. Some homeowners prefer to have a plumber handle it.

Do I need a separate filtered-water faucet with the H-104? Yes. The H-104 filters water from the cold supply and delivers it through its own dedicated faucet. The existing kitchen faucet continues to deliver unfiltered water from the main cold line. Keeping them separate preserves the filter cartridge by not filtering water used for washing dishes or cleaning.

What is the cost per gallon of filtered water from an H-104? Roughly $0.07 to $0.10 per gallon over the cartridge life with an authentic Everpure cartridge. Compared to bottled water at $1 or more per gallon equivalent, the economics favor filtered tap for any household using the system regularly.

Where can I buy an Everpure H-104 with fast shipping? Water Filters FAST carries authentic Everpure H-104 cartridges with same-day shipping on weekday orders before 1pm Central. Free shipping over $75, satisfaction guarantee, and 30-day returns.