Repipes & Supply Line Replacement
Galvanised supply from the 1940s and 50s closes up from the inside long before it leaks. If your pressure has been dropping for years rather than suddenly, that is usually why.
NJM Mechanical & Contracting
Plumbing, Heating & Cooling In Farmingdale
Farmingdale is three places at once — an incorporated village, South Farmingdale beside it, and East Farmingdale over the Suffolk line in our own Town of Babylon. Which building department your job goes through depends on which one you are standing in.
NASSAU & SUFFOLK SIDESPOST-WAR HOUSING24/7 EMERGENCYLICENSED
Licensed & Insured
Master Plumber
TASK 86/87 Certified
Navien NSS Certified
22+ YEARS ON LONG ISLANDGet Your Free Estimate
LICENSED & INSURED · NASSAU & SUFFOLK
PLUMBING · HEATING · COOLING · CONTRACTING
Have An Emergency? We’re Available 24/7.
631-587-0085WE ANSWER EVERY CALLFarmingdale
Plumbing, Heating & Cooling Across Farmingdale
Farmingdale is three places wearing one ZIP code. The Village of Farmingdale is incorporated, and sits in the Town of Oyster Bay in Nassau County. South Farmingdale is unincorporated, and is also Oyster Bay. East Farmingdale is over the Suffolk line in the Town of Babylon — the same town as our shop. Which of the three you are in decides which building department your job goes through, and it is not obvious from the address.
What the three have in common is the housing. Roughly two thirds of the homes in 11735 went up between 1940 and 1959 — post-war Capes, ranches and expanded Capes that are now sixty-five to eighty-five years old. That is the age where original galvanised supply, cast iron waste and first-or-second-generation heating plant all reach the end of the line at roughly the same time, usually within a few years of each other.
24/7 Emergency ServiceLicensed & Insured
Master PlumberLicensed to pull permits
TASK 86/87Certified for gas work
Navien NSSFactory-trained on tankless
22+ years on Long Island · Plumbing, heating, cooling, gas and contracting under one roof
Before you call
Two kinds of visit. You’ll know which before we come.
We don’t charge to quote a job. We do charge to find a problem nobody has identified yet. Which one you need — and what it costs — gets agreed on the phone, so nothing about the cost is a surprise on the doorstep.
The rate you are told is the rate
You get the number on the phone, before anyone is dispatched, and it is what you are charged when the technician arrives. One rate across all four trades — plumbing, heating, cooling and gas.
What it pays for
A licensed, insured technician carrying the certifications the work needs, and the time to find what has actually failed — not a quick look and a guess.
Watch for the bait and switch
A call-out advertised at almost nothing gets recovered once someone is standing in your basement. Get the number before anyone travels — from us, or from anyone else you call — and hold them to it when they arrive.
Financing on larger jobs
A boiler that fails in January is not a purchase anyone planned. Financing is available on the big-ticket work, so a system replacement does not have to come out of savings in one go.
What it is normally used for
Boiler, furnace and water heater replacement, a full air conditioning system, a whole-house repipe, sewer and water main work, and larger contracting jobs — kitchens, bathrooms, dormers and extensions.
When to bring it up
At the estimate, before anything is scheduled. It is worth asking even if you think you will not need it, because knowing it is there changes what you are willing to consider fixing properly.
What it does not change
The price of the job. The quote is the quote whether you finance it or not — and on a straightforward repair it is usually not worth the paperwork. We will tell you which one you are looking at.
Call 631-587-0085Not sure which one you need? Call and describe it — we will tell you before we book anything.
What We Do Here
Services In Farmingdale
Water Heaters & Tankless
Replacement and installation, including high-efficiency tankless. We are Navien NSS certified, which matters when a tankless unit needs more than a reset.
Boilers & Furnaces
Heating plant in a post-war house has usually been replaced once already. We install, service and repair both, and we will tell you plainly when a repair is worth doing.
Central Air & Ductless
Full systems and ductless mini-splits — the usual answer in a Cape where there was never anywhere to run a duct.
Gas Lines & Inspections
TASK 86/87 certified gas work, including pressure testing and code compliance. Oyster Bay requires a permit for heating units and fuel storage tanks as well as for the pipe.
Drains, Sewers & Backwater Valves
The Village is sewered, and Village code requires an approved backwater valve where fixtures sit less than three feet above the main sewer. A basement bathroom in an older village house is exactly that situation.
Kitchens & Bathrooms
Full renovations where the plumbing, gas and mechanical are handled by the same licensed team rather than three subcontractors blaming each other.
24/7 Emergency Service
Round the clock, every day of the year. One number for plumbing, heating, cooling and gas.
Current Offers
Money Off, Plainly Stated
What it says on the coupon is what comes off the bill. Mention it when you call.
Common Questions
Frequently Asked Questions
Which building department issues a permit in Farmingdale?
It depends which Farmingdale you are in. Inside the incorporated Village, it is the Village of Farmingdale Building Department on Main Street. In South Farmingdale and the other unincorporated areas, it is the Town of Oyster Bay Building Division. East Farmingdale is across the county line in the Town of Babylon, Suffolk County. Call 631-587-0085 with the address and we will tell you which one applies to your job.
Do I need a water softener in Farmingdale?
Almost certainly not. Both suppliers here draw from the Magothy aquifer, and their own annual reports put total hardness in the low single figures to low tens of milligrams per litre — that is very soft water, well under one grain per gallon. If you have staining, the more likely culprit on the South Farmingdale side is iron; the district there runs several iron removal facilities for exactly that reason. It is worth identifying which problem you actually have before buying equipment for the wrong one.
What is a backwater valve, and does my house need one?
It is a one-way valve on the house drain that stops sewage backing up into the lowest fixtures when the main sewer surcharges. Village of Farmingdale code requires an approved backwater valve where a fixture sits less than three feet above the level of the main sewer — which in practice means most basement bathrooms and laundry hookups in the village. If you have ever had water come up through a basement floor drain, this is the fix.
Is East Farmingdale different from the rest?
Yes, in two ways that matter. It is in Suffolk County and the Town of Babylon rather than Nassau and Oyster Bay, so permitting runs through the Town. And it is not fully sewered — Suffolk County has an active Southwest Sewer District expansion project covering parts of the area, and properties outside it are on individual systems.
How far is Farmingdale from your shop?
Under ten miles, more or less due west along Conklin Street. We are at 31 Magro Drive in North Babylon, which puts most of Farmingdale within about fifteen minutes in normal traffic.
Are estimates free?
If you know what you want done, yes — free and with no obligation. If something has failed and nobody knows why yet, that is a diagnostic call rather than an estimate, and the service call fee applies. We will tell you which one applies before anyone gets in a truck. Call 631-587-0085.
Service Area
Proudly Serving Long Island and Surrounding Areas.
Based in North Babylon, working across both counties — close enough to get there fast, local enough to know the housing stock and the permit offices.
Find Service Near You!
- Long Island
- Nassau County
- Suffolk County
Towns We Serve
Proudly serving all of Nassau and Suffolk County, with deep local roots near our North Babylon home base.
Get A Free EstimateWhat Long Island Says
Reviews From Homes & Businesses We've Served
5 out of 5 stars
The experience I had with with NJM Mechanical & Contracting was a pleasant one. I had the pleasure of doing business with Neil. The work I had done was a basement entrance to my yard and it came out wonderful. The work performed as well as the communication is 10/10.
Nick UrziaJune 2026
5 out of 5 stars
Neil has handled all my A/C needs over the years. He's very communicative and open about service charges. He never steers you wrong
Jim JacksonMay 2026
5 out of 5 stars
As always, Neil is a pleasure to have as my plumber. He is so professional and knowledgeable. I wouldn't use anyone else! I highly, highly recommend him.
Fritzi R.May 2026
Need A Licensed Plumber In Farmingdale?
Free estimates with no obligation, 24/7 emergency response, and 22+ years serving homes and businesses across Nassau and Suffolk County.