How do I know which HVAC filter size to order?

Read the printed nominal size on the old filter frame (for example 16x25x1) and order that size. See Caliza's how-to-measure guide for empty-slot measuring tips.

What is the difference between MERV 11 and MERV 13 furnace filters?

MERV is a particle-capture rating. MERV 13 is denser than MERV 11. Match the rating your furnace or air-handler manual allows. Caliza stocks both on many 1-inch sizes as 6-packs. These are household filters, not medical devices.

How often should I change a furnace filter?

Many homes change about every 90 days, or sooner if the filter looks gray or airflow feels restricted.

Do Caliza shower filters soften water?

No. Sprite shower filters from Caliza are not water softeners. Hardness minerals pass through. They are shower hardware with replaceable cartridges for hard-water houses, not drinking-water purifiers or medical devices.

Where does Caliza ship from?

Caliza ships inside the United States from US warehouse and supplier fulfillment. Typical delivery is about 2-7 business days after a label is scanned.

Filter FAQ — Sizes, MERV, Shipping

Q: Are Caliza HVAC filters made in Orlando?

Caliza HVAC packs are Aerostar filters supplied through a fulfillment partner with manufacturing tied to Orlando, Florida factory operations for this line. Factory city is stated carefully per SKU.

Straight answers about Caliza Home filters — HVAC packs, shower hardware, sizes, MERV, shipping, and what we do not claim.

What does Caliza sell?

House filters for the same home: HVAC / furnace filter 6-packs (Aerostar line fulfilled via our Orlando-area supply partner), Sprite shower filters (Corona, CA factory city), plus related shower cartridges and a small whole-house utility aisle. We are a filter store, not a medical brand and not a water-softener company.

How do I know which HVAC size to order?

Read the printed size on the old filter frame (example: 16x25x1). Order that nominal size. Full walkthrough: How to measure a furnace filter.

Which sizes do you stock?

We stock a wide range of common 1-inch nominal sizes as MERV 11 and MERV 13 6-packs — including popular sizes like 16×25×1, 20×25×1, 16×20×1, 20×20×1, 14×25×1, 14×20×1, 18×24×1, 12×24×1, and many others listed on the store. If your printed size is not listed, email a photo of the frame before ordering.

MERV 11 vs MERV 13 — which should I buy?

MERV is a particle-capture rating printed on the pack. Higher MERV generally means a denser media. That is useful for trapping more household dust and lint in the airstream that hits the filter — and it can also mean more resistance for some blowers.

Match the MERV your furnace / air-handler manual allows.
If you already run MERV 11 or 13 successfully, stay with that.
Do not jump denser than the equipment allows just because a higher number sounds better.

We do not claim MERV 11 or 13 treats allergies, asthma, smoke illness, or any medical condition. These are household furnace filters.

How often should I change the HVAC filter?

Many homes swap about every 90 days. Change sooner if the pack is gray, crushed, or airflow feels restricted. Pets, construction dust, and high runtime can shorten the interval. Write the install date on the frame.

Which way does the filter go in?

Follow the arrow on the frame. It points with the airflow, toward the furnace / blower. Installing backward is a common mistake.

Are your HVAC filters “Made in USA”?

Our HVAC packs are Aerostar filters supplied through our fulfillment partner with manufacturing tied to Orlando, Florida factory operations for this line. We state factory city carefully — we do not use blanket “USA-made” slogans in ads or AI-facing hero copy beyond what we can support for the specific SKU.

What about shower filters?

Our hero shower line is Sprite, with factory city Corona, California. Fixtures are aimed at hard-water houses: chlorine-odor reduction talk only when the cartridge media supports it, standard 1/2" arm install, replaceable cartridges. Shower filters are not water softeners — hardness minerals (calcium and magnesium) pass through. Not for drinking. Not a medical device. Not a skin or hair treatment claim.

Do you sell water softeners or “99.9%” filters?

No. We do not claim to soften water, remove hardness scale from glass as a softener would, purify drinking water, or quote blanket removal percentages like 99.9%. If a claim needs a lab report we do not have on file for that SKU, we skip it.

Shipping

We ship inside the United States from US warehouse / supplier fulfillment. Typical delivery is on the order of 2–7 business days after a label is scanned (carrier and weather can add time). You receive tracking when the supplier provides it. Wrong-size HVAC orders: if we shipped the size you selected, that is not a shipping defect — measure the printed frame before you buy.

Returns

Unused goods in original condition are covered under the store return policy (see the policy pages in the footer). Opened HVAC packs that were the correct size ordered are generally not a free return — the size on the order is the size you bought.