A filter housing should be selected around the cartridge and the system—not by length alone. A 10-inch housing is often easier to fit and service in a compact installation, while a 20-inch housing can provide more filter media when the matching cartridge and system are designed for it. The right choice is the one whose complete specifications match your plumbing.
Start with the cartridge format
Confirm the cartridge length and diameter accepted by the exact housing model. “10-inch” and “20-inch” describe nominal families, not every critical dimension. Standard-diameter and larger-diameter housings are not interchangeable, and an incorrect cartridge can prevent the cap from sealing or allow water to bypass the media.
- Match nominal cartridge length and diameter.
- Confirm the cartridge end style required by the housing.
- Use the exact housing and cartridge part numbers when replacing an existing unit.
Compare installation space and service clearance
Measure the wall area, but also leave room below the housing so the sump can be removed. Account for the bracket, wrench movement, shutoff valves and the ability to catch water during service. A longer housing needs more vertical clearance and may be less practical in a tight mechanical room.
Match the plumbing connections
Check inlet and outlet size, thread type and flow direction. Do not assume two housings with the same nominal length have the same ports. Reducing or enlarging fittings can affect the installation and should be evaluated as part of the complete system.
Consider flow and pressure—not just size
Housing length by itself does not establish the final flow rate or pressure drop. The cartridge media, micron rating, contaminant loading and manufacturer limits all matter. Compare the published specifications for the exact housing and cartridge combination, and stay within the listed pressure and temperature limits.
Think about replacement frequency
A larger cartridge may offer more media, but service life still depends on water quality and consumption. Replace cartridges based on the manufacturer’s guidance and actual pressure or flow performance. Never extend service solely because the cartridge looks clean.
Quick selection checklist
- Identify the contaminant or treatment goal.
- Confirm cartridge length, diameter and media.
- Measure installation and service clearance.
- Match port size, thread type and flow direction.
- Compare rated pressure, temperature and flow information.
- Verify the housing, cartridge and replacement seal part numbers.
- Confirm the quantity shown on the product page.
View the Boshart 10-inch housing listing, compare options in Boshart water filtration, or ask Carter Goods for order help when you have a model number or a mixed project list.
Installation and product selection must follow the manufacturer’s instructions and applicable plumbing codes. For technical documentation, see Boshart’s filtration resources.