| Business | Phone |
| A B Jones Air Condiitoning 5716 Industry Ln, Frederick 21704 | (301) 948-4431 |
| Aaa Leaks Plumbing & Heating Frederick 21702 | (301) 846-4460 |
| All Around Plumbing Inc 419 N Market St, Frederick 21701 | (301) 698-1028 |
| All State Plumbing Heating 33 E Patrick St, Frederick 21701 | (301) 694-5790 |
| American Residential Svc 4640 Wedgewood Blvd # 103, Frederick 21703 | (301) 253-4763 |
| Anders Plumbing Inc 8209 Chestnut Grove Rd, Frederick 21701 | (301) 831-4246 |
| Associates Plumbing 93 Monocacy Blvd # A6, Frederick 21701 | (301) 695-4003 |
| Atm Plumbing Inc Frederick 21701 | (301) 694-5725 |
| Bob Ne Waltz Plumbing & Htg 8098 Hillmark Ct, Frederick 21704 | (301) 662-3588 |
| Brown's Plumbing 8546 Fingerboard Rd, Frederick 21704 | (301) 482-1633 |
| Classic Plumbing & Heating Inc Frederick 21701 | (301) 695-7934 |
| Crown Plumbing & Heating 9929 Gas House Pike, Frederick 21701 | (301) 898-8501 |
| Crum Inc 3202 Basford Rd, Frederick 21703 | (301) 663-0050 |
| Dennison Plumbing & Heating 7809 Ridge Rd, Frederick 21702 | (301) 473-4015 |
| Dgi Plumbing & Heating 1576 Andover Ln, Frederick 21702 | (301) 663-8420 |
| Domestic Plumbing & Heating 5702 Industry Ln # B20, Frederick 21704 | (301) 695-6640 |
| Fellows Plumbing & Heating Inc 11 Byte Ct # B, Frederick 21702 | (301) 668-7711 |
| First Quality Plumbers 33 E Patrick St, Frederick 21701 | (301) 631-0010 |
| Frederick Plumbing & Htg Co 10 Key Ave, Frederick 21701 | (301) 663-4175 |
| Glenn E Waltz Plumbing & Heat 532 E Church St, Frederick 21701 | (301) 663-4417 |
| Hughes Supply 4441 Buckeystown Pike, Frederick 21704 | (301) 874-0909 |
| Joe's Plumbing & Heating Frederick 21701 | (301) 695-7576 |
| L H Cranston 7310 Grove Rd # 109, Frederick 21704 | (301) 631-8190 |
| Len The Plumber Frederick 21701 | (301) 694-0090 |
| Merhl Allen Wachter Plumbing 13 W 12th St, Frederick 21701 | (301) 663-9183 |
| Nelson Commercial Plumbing 10209 Allview Dr, Frederick 21701 | (301) 898-3448 |
| Nelson Plumbing & Heating 413 N East St, Frederick 21701 | (301) 663-6909 |
| R J Renner Master Plumber 5712 Industry Ln, Frederick 21704 | (301) 695-5586 |
| R J Smith Plumbing & Heating 7704 Mckaig Rd, Frederick 21701 | (301) 898-9003 |
| R Redmond Plumbing & Htg Inc 838 Chadwick Cir, Frederick 21701 | (301) 663-3625 |
| Roto-Rooter Plumbing & Drain Po Box 1002, Frederick 21702 | (301) 695-1750 |
| Sears Plumbing 5714 Industry Ln, Frederick 21704 | (301) 698-2592 |
| Tri-County Pump Svc 6711 Old National Pike Rd, Frederick 21701 | (301) 662-5220 |
| Tyler Streamline 1573 Tilco Dr, Frederick 21704 | (301) 694-9916 |
| Tyler Streamline Plumbing 1802 Rainbow Falls Ct, Frederick 21702 | (301) 694-9916 |
| Walter W King Plumbing & Htg 5305 Kings Ct, Frederick 21703 | (301) 662-6990 |