COWAY MARYLAND
Water Purifiers & Air Purifiers Rental
Rent or buy Coway water purifiers, air purifiers, bidets, water softeners, and massage chairs in Howard County — including Ellicott City, Columbia, and Clarksville — as well as Gaithersburg, Rockville, Bethesda, and Baltimore. Installation and maintenance every 6 months are handled through Coway's official branch network.
- 13States Served
- 6In-home visits every 6 months
- FREEFree new installation
- 1:11:1 consultation in Korean
Maryland Service Areas
Select a region to see the main cities we service, local installation notes, and frequently asked questions for that area. If your city isn't listed, just share your address and we'll confirm whether installation is available.
Howard County
Maryland's Korean-American hub, including Ellicott City and Columbia
- Ellicott City
- Columbia
- Clarksville
This is our highest-volume area for Korean-community consultations and installs. Water here is purchased from Baltimore City (west of I-95) or WSSC (east of I-95), with average hardness around 70 mg/L.
Can water quality differ within Howard County itself?
Yes, the supplier splits along I-95. Share your address and we'll recommend products based on your specific supplier.
Montgomery County
Suburbs north of Washington, DC
- Gaithersburg
- Rockville
- Potomac
- Bethesda
- Silver Spring
This WSSC service area draws mainly from the Potomac River, with average hardness of 120–130 mg/L — relatively hard water for Maryland. Many households here install a purifier and softener together.
Is Montgomery County's water on the harder side?
Yes — WSSC reports average hardness of 120–130 mg/L for Potomac River water in this area. If scale buildup is a concern, consider adding a softener.
Baltimore
Baltimore City and nearby areas
- Baltimore
This area draws from the Liberty, Prettyboy, and Loch Raven reservoirs, with a mix of downtown high-rise condos and townhouses, so we confirm your building type before installation.
Do you install in downtown Baltimore condos?
Yes. Some buildings have delivery restrictions, so please share the building name and we'll check in advance.
Anne Arundel County
South of Baltimore
- Glen Burnie
- Pasadena
A single-family-home area south of Baltimore with a mix of new and older construction. We recommend a countertop or under-sink model based on your plumbing condition during consultation.
Can an under-sink unit be installed in an older home?
In most cases, yes. Sending photos of the under-sink space and plumbing before the visit helps us give you a more precise recommendation.
Frederick County
Western Maryland
- Frederick
An outlying area farther from the branch than Montgomery County, so we group visits with nearby areas. It's served by a different water utility, so water quality may differ from Montgomery's.
Does Frederick still get 6-month maintenance visits?
Yes, as long as your area is serviceable you'll get the same 6-month visit schedule, coordinated together with nearby areas.
Carroll County
Northwest of Baltimore
- Linwood
A more remote outlying area from the branch, where some homes rely on private wells, so we base our product recommendation on your well-water test results.
Do you install in farther areas like Linwood?
If your area is serviceable, you'll get the same installation and 6-month maintenance terms. Since it's farther from the branch, visit scheduling needs to be coordinated in advance.
Installation may be difficult in areas more than 70 miles from a Coway branch or authorized dealer.
Maryland Tap Water: It Depends on Which River
Montgomery County mainly uses Potomac River water, the Laurel area uses the Patuxent River, and Baltimore uses reservoir water. Agency reports show tap water meets federal and state standards, though hardness nearly doubles depending on the source.
U.S. Geological Survey (USGS) scale: 0–60 soft, 61–120 moderate, 121–180 hard, 181+ very hard. WSSC figures reflect its published average range; Howard County is the 2025 average.
Montgomery · Prince George's
108 years
Without a drinking water quality violation
- Serves about 1.9M from the Potomac and Patuxent Rivers
- 500,000 lab tests per year
- Lead 90th percentile below 2.0 ppb; 0 of 69 sites over the action level
- Removed all known lead service lines from the distribution system in the early 2000s
Howard County
70
mg/L average hardness (WSSC supply) · range 58–86 · moderate
- West of I-95 supplied by Baltimore City; east purchases water from WSSC
- Lead 90th percentile 4 ppb; 0 of 58 sites over the action level
- Maryland banned lead service line installation in 1972
- No 2025 violations
Baltimore
2.74
ppb lead 90th percentile · action level 15 ppb
- Serves about 1.8M from 3 reservoirs: Liberty, Prettyboy, and Loch Raven
- 100,000+ water analyses per year
- All PFOA/PFOS measurements below the federal 4 ppt standard
- Zero sites over the action level in lead testing
Watch for Scale in Montgomery
WSSC lists Potomac River water hardness at 120–130 mg/L on average — about double the Patuxent's. If scale on kettles or shower enclosures bothers you, consider adding a softener.
Chlorine Taste and Odor
WSSC, Howard County, and the City of Baltimore all use chlorine-based disinfectants. They stay within safety standards, but some households are sensitive to the taste and odor.
Different Water in the Same County
Howard County's water provider changes at I-95. Send us your address and we'll recommend products based on your actual provider.
These figures are system-wide data published by the agencies; actual water quality at your home may vary by water provider, season, and building plumbing. Check your local water provider's annual quality report for precise figures.
Popular with Maryland Households
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5 Steps to Installation
- 1ConsultKakaoTalk or phone
- 2Place your orderProduct and address confirmed
- 3AgreementIdentity and autopay details
- 4SchedulingConfirmed by phone or email
- 5Installation6-month maintenance begins
Do you install in Ellicott City or Columbia too?
Yes — installation is available across Howard County, including Ellicott City and Columbia, and Montgomery County, including Gaithersburg. For Baltimore and Frederick, send us your address and we'll confirm availability.
Is Maryland tap water safe to drink as is?
According to 2025 reports from WSSC Water, Howard County, and the City of Baltimore, tap water meets federal and state standards. Households usually choose a purifier for chlorine taste, water taste, or mineral content concerns.
Is Montgomery County's water on the harder side?
WSSC lists the Potomac River water used by most of Montgomery County at 120–130 mg/L on average. Use a purifier for drinking water; if scale on showers and household water bothers you, consider adding a softener.
Can I install in a townhouse or apartment?
Most homes can be fitted, but renters should check with their landlord or management office first. We'll recommend the right model for your home — countertop or undersink — during your consultation.
How are filters maintained after installation?
During your rental, a Coway specialist visits every 6 months to replace filters and inspect your products. Maintenance is included in your rental fee.
Maryland Installation Consultation
Consultations are free — send us your address and we'll confirm installation availability right away.





