Tankless Water Heater Installation Services in Largo, FL

  • Transparent Pricing
  • Local, Family-Owned Experts
  • Prompt, Code-Compliant Installation
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Never Run Out of Hot Water Again with a Custom Tankless Upgrade

Positively Plumbing installs, replaces, and services both gas tankless water heaters and electric tankless heaters across Largo. Kevin runs the crew. Before we sell you anything, we tell you honestly whether tankless makes sense for your home or whether tank-style water heaters are the smarter spend — because the answer depends on your gas or electrical setup, your hot water demand, and your budget. You get a written price before the work starts and no surprises on the invoice.

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Is Tankless Right for Your Home? An Honest Answer

We’re straight with people about this: tankless is a great fit for some homes and the wrong call for others.
Here’s how we frame it.

Tankless Makes Sense When

You want endless hot water; you’re tired of running out mid-shower; you want to free up the closet or garage space a tank takes up; or your household demand and gas/electrical setup support it.

A Tank May Be the Smarter Spend When

Your budget favors a lower upfront cost, your home would need expensive gas line installation or electrical upgrades to support a tankless unit, or your hot water demand is modest.

We’ll look at your setup, tell you what each option costs to run, and let you decide. No steering you toward the bigger ticket.

Our Tankless Water Heater Services

Whether you need a seamless tank conversion or an honest diagnostic on a failing unit, we have you covered.

Tankless Installation

New tankless installation sized to your home’s hot water demand, with the gas line installation, electrical, and venting done to code. We handle the whole job — a complete, safe installation, not just the hang-and-connect.

Tank-to-Tankless Conversion

Switching from an existing water heater to tankless. We assess what your gas line, electrical, and venting need, quote it honestly, and schedule the conversion so you’re not without hot water long. We remove the old unit and reuse or replace existing water lines as needed.

Tankless Replacement

Replacing an aging or failed tankless unit. Tankless replacement is scheduled promptly so you’re back to hot water fast.

Tankless Repair

Ignition problems, error codes, scale buildup, and flow issues. We diagnose the actual fault and tell you honestly whether it’s a repair or time for a replacement.

Descaling and Maintenance

Florida’s hard water scales tankless heat exchangers over time. Regular descaling keeps the unit efficient and protects its service life — the maintenance that makes tankless worth it.

Our Tankless Water Heater Installation Process

Most installs take 4 to 10 hours and finish the same day. Here’s how a licensed,
permitted heater installation runs from first visit to hot water at the tap.

Step 01

Assessment and Sizing

A professional plumber checks your natural gas supply or electrical capacity, venting, and hot water demand, then sizes the right tankless water heater based on flow rate in GPM. You get a written estimate covering the new unit and every piece of work needed to install it.

Step 02

Written Price, Then Install

We provide a clear breakdown of the unit, labor, and any gas, electrical, or venting work before anything starts. Nothing begins until you sign off — no hourly meter, no surprise add-ons.

Step 03

Permitted, Code-Compliant Installation

We pull the permit, mount the new heater, and connect the water supply line, gas, and electrical connections to the manufacturer’s installation instructions and local codes. We lay drop cloths down and leave the area clean.

Step 04

Testing, Walkthrough, and Warranty

We test the unit, confirm consistent hot water at your fixtures, and walk you through operation and maintenance. You get the manufacturer’s warranty and our workmanship warranty in writing.

Why Pinellas County Homeowners Choose Positively Plumbing

Honest Tank-vs-Tankless Advice

We tell you which option actually fits your home and budget, not which one costs more. If a tank is the smarter spend, we say so.

Licensed and Insured Professionals

Fully licensed and insured, carrying general liability and workers’ compensation. All gas, electrical, and venting work is done to code on the first pass.

Upfront Pricing in Writing

The unit, labor, and any gas or electrical work are spelled out before we start. No hourly meter, no surprise charges.

Family-Owned and Locally Operated

We are a Largo-based company that values community and personalized service. Kevin runs the trucks, so the plumber who installs your unit is the same one who services it.

One Number for Everything After

The plumber who installs your tankless is the same one for its descaling, repairs, and your next plumbing job. No re-explaining the house to a new face.

No Hot Water Right Now? We Answer Day or Night


A failed water heater doesn’t wait for business hours. Positively Plumbing runs 24/7 emergency response across Pinellas County. A licensed plumber picks up, gets a truck on the way, and gives you a written price before any work begins.

We keep tank sizes on the truck for same-day replacement and schedule tankless replacement promptly, so you’re back to hot water fast.

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Service Areas

We provide hydro jetting and drain cleaning plumbing services across Largo, Clearwater,
Pinellas Park, and communities throughout the greater Tampa Bay area.

Largo
Ridgecrest
Belleair Bluffs
Belleair
Seminole
Harbor Bluffs
Indian Rocks Beach
Belleair Beach
Clearwater
Bardmoor
Belleair Shore
Indian Shores
Redington Shores
Madeira Beach
Redington Beach
Feather Sound
N. Redington Beach

Not sure if you’re in our service area? Call (727) 625-0603 — we’ll tell you straight.

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What Customers Say About Us Online

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Frequently Asked Questions

Endless hot water, lower energy bills, a longer lifespan, saved space, and no risk of a large tank rupturing across your floor.

A tankless system heats water as it flows, so you get hot water on demand without running out mid-shower or waiting on a tank to reheat between loads.

It only fires when you open a hot water faucet, which cuts the standby loss traditional water heaters rack up reheating the same water all day with nobody home — that’s where the energy-efficient claim actually comes from. Installed and maintained right, a tankless unit typically outlasts a tank water heater by years, which offsets more of the upfront cost over time.

Tampa Bay has one real advantage here: warm incoming groundwater means a smaller temperature rise to reach your target, so a gas tankless water heater in this climate delivers a higher usable flow rate than the same unit would up north.

Two practical wins come with it — the wall-mounted unit saves space in the closet, garage, or utility room a bulky tank occupies, and there’s no 40-gallon tank waiting to fail at the end of its life.

A tankless unit isn’t a like-for-like swap for a tank, and saying so up front is part of an honest quote. A proper installation involves:

  • Correct location and clearances. The unit needs a suitable spot with manufacturer clearances and short pipe runs — long runs lose heat and leave you waiting at the faucet.
  • Adequate gas supply. Gas tankless heaters need larger gas lines than tank models — often an upgrade to 1-inch black iron pipe, sized to the load, with a shut-off valve and sediment trap at the unit. Your gas meter has to supply enough for it.
  • Proper venting. High-efficiency units vent through specialized PVC, and the exhaust has to carry combustion gas out safely with enough combustion air reaching the burner. Manufacturer venting requirements aren’t optional.
  • Water and electrical connections. Supply and hot water lines get connected with a pressure relief valve fitted for safety. Most units also need a dedicated electrical circuit, hard-wired or outlet, tied in to code.

It varies with the unit you choose and what your home needs to support it — gas line capacity, electrical, and venting all factor in, and a straight swap costs less than a full tank-to-tankless conversion that requires gas or electrical upgrades. We assess your setup and put a written price in front of you before any work starts.

Most installations run 4 to 10 hours depending on complexity, and the majority finish in a single day. Gas installations take longer than electric because the gas line often needs upsizing for the burner’s demand and the exhaust vent usually needs upgrading — both add cost as well as hours. A straight electric swap with adequate electrical supply already in place lands at the short end.

Yes. Professional installers pull mandatory permits on every water heater installation, and local inspectors check specifically for a proper pressure relief valve and expansion measures like an expansion tank where water pressure calls for one.

Plumbers in Largo have to be licensed and insured to do the work legally. Improper installation voids the manufacturer warranty and creates genuine safety risk, which is the practical reason to skip the handyman quote.

More than swapping a tank heater out for a new unit. A gas tankless water heater draws far more at peak than an old system does, so the gas line usually needs upsizing to feed the burner, and the exhaust vent gets replaced with the specialized PVC high-efficiency units require. Electrical connections come next — most gas models still need a dedicated circuit for the controls and ignition.

From there it’s the water side: reworking the water pipes so runs stay short, fitting the safety valves, and purging air from the lines before the first firing. Sizing runs on flow rate in GPM, and several factors decide the right unit — fuel type, peak demand, and what your existing gas and electrical already support. Professional tankless gas water heater installation is what gets you code compliance, a valid warranty, and the 15-to-20-year lifespan these units are rated for.

That’s the work behind endless hot water. Qualified professionals size it, permit it, and hand you the owner’s manual with a walkthrough at the end.

A tankless unit typically lasts 15 to 20 years, well past what most tank water heaters reach. That number depends on maintenance more than anything else — the heat exchanger has to stay clear of mineral buildup to hit the top of that range.

Yes, and it matters more here than in most places. Pinellas County groundwater is hard, so scale builds on the heat exchanger faster, and descaling flushes that buildup off. Skipping it can void your warranty. A descaling valve makes the flush straightforward, and pairing the unit with a water softener slows buildup considerably.

Get Your Tankless Water Heater Estimate Today!

Thinking about tankless? Contact Positively Plumbing today for an honest assessment and a written estimate. You’ll get a straight answer on whether tankless fits your home, a clear price, and work you’ll be glad to recommend.

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