Why are some plumbers against tankless water heaters?

Because bad installs give tankless a bad reputation. A tankless with an undersized gas line will starve under load, cycle, and fail prematurely. A tankless on unsoftened Dallas water scales up in 3-4 years. Done right — correct BTU sizing, upgraded gas line, direct vent, and a softener — a tankless outlasts two tank replacements.

Can one tankless run two showers at once in my Addison home?

Yes, if the unit is sized correctly. A typical 199k BTU condensing tankless delivers roughly 9-11 GPM at a 70°F rise — enough for two simultaneous showers plus a kitchen tap. A 160k BTU unit struggles above two fixtures. We size based on your actual household peak demand, not spec-sheet claims.

Rinnai, Navien, or Noritz — which brand do you install in Addison?

We install and service all three. Rinnai has the deepest parts network in DFW, Navien condensing units handle recirculation elegantly, and Noritz offers strong commercial-grade models. We recommend based on your gas capacity, venting path, and recirculation preference — not on which brand pays us the most.

Does a tankless water heater need yearly maintenance?

Yes — annual vinegar or commercial-descaler flush through the service ports is required to maintain the manufacturer warranty on Dallas hard water. Skip it and the heat exchanger scales up. We offer a maintenance plan that bundles the annual flush and a system inspection.

Does the Town of Addison require a permit for a tankless install?

Yes. Tankless installs (including replacements) require a Town of Addison plumbing permit and inspection — gas line sizing changes and venting routing both get inspected. We pull the permit, coordinate the inspection, and hand you the passing paperwork for your resale file.

How long does a tankless water heater installation take in Addison?

A straight tank-to-tankless swap where gas capacity and venting are adequate is a one-day job. Installs that need a gas line resize or a new vent run through walls are typically 1.5-2 days. We quote the actual duration flat before we start.

Tankless Water Heater Addison TX

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A tankless water heater installation in Addison, TX delivers endless hot water and 20-year equipment life — but only when the gas line is correctly sized for the 199,000 BTU load, the direct vent is routed to code, and the system is paired with a softener for Dallas hard water. Belt Line Plumbing installs Rinnai, Navien, and Noritz tankless units with the gas resize, venting, condensate drain, and softener recommendation included in one flat quote.

Tankless water heater installation in Addison means endless hot water, a smaller footprint, and 20-year equipment life — IF the install is sized to your gas line, vented correctly, and paired with a softener for Dallas hard water. Belt Line Plumbing installs Rinnai, Navien, and Noritz tankless systems across Addison and the Dallas North Tollway corridor. Most tankless conversions finish same-day; new-construction installs include the gas resize, direct vent, condensate drain, and softener recommendation in one quote.

Signs tankless is the right call for your Addison home

Family runs out of hot water in back-to-back showers
Current tank is 10+ years old and failing on Dallas hard water
You want to free up garage or utility-closet floor space
Energy bills on an electric tank are climbing
Planning a kitchen or bath addition that demands more flow
You want a 20-year unit instead of a 10-year replacement cycle

What's included with our tankless water heater installation

Every tankless water heater installation job with Belt Line Plumbing includes the deliverables below — quoted flat, in writing, before we start.

In-home BTU + GPM demand audit

We measure incoming water temperature, count simultaneous-use fixtures, and calculate the exact unit size you need — no spec-sheet guessing.

Gas line resize when required

A 40k BTU tank line will NOT feed a 199k BTU tankless. We check main gas-run capacity and upsize when needed, or quote an Atmos service upgrade if the meter is too small.

Code-compliant direct vent + condensate drain

Stainless concentric venting routed to code, condensate drain plumbed to an approved receptor — no corrugated flex, no dumped condensate on the slab.

Softener recommendation (strongly advised)

Dallas hard water (8-11 grains/gal) scales a tankless heat exchanger in 3-4 years. Bundle a softener at install and we knock $50 off the softener price.

Permit, inspection, and manufacturer warranty registration

Addison plumbing permit pulled, inspection scheduled, first-startup performed, and your manufacturer warranty registered in your name — not ours.

How we install a tankless heater — the right way

1
In-home demand audit
We count fixtures, measure incoming water temperature, and calculate required BTU and flow rate (GPM). A 1-2 bath house needs a very different unit from a 4-bath Highland Park estate.
2
Gas line sizing (this kills most bad installs)
A 199,000 BTU tankless almost always needs a bigger gas line than your old 40,000 BTU tank. We check the main gas run and either upsize it or recommend a condensing propane-ready alternative.
3
Direct vent + condensate drain
Modern condensing tankless units need stainless concentric venting and a condensate drain. We route both to code — no corrugated flex, no dumped condensate.
4
Softener recommendation (Dallas water will scale it)
Dallas Water Utilities runs 8-11 grains of hardness. Without softened water, your tankless heat exchanger scales up in 3-4 years and manufacturer warranty gets rejected. We quote a softener bundle at install.
5
Permit + first startup
Addison requires a plumbing permit for new tankless installs. We pull the permit, coordinate the inspection, do first-startup, teach you the maintenance interval (annual descale), and register the manufacturer warranty in your name.

What drives the price

Every job we do is flat-quoted before we start — no hourly meter. The factors below determine what your specific number will be:

Unit size (gas BTU / GPM) matched to actual household demand
Gas line resize when the existing line is undersized for 199k BTU
Venting path and length (longer vents and tight routing add labor)
Softener bundle vs. standalone install (softener strongly recommended)
Removal and recycling of your old tank
Town of Addison plumbing permit and inspection

Belt Line Plumbing — tankless water heater installation on-site in the Addison / Tollway corridor.

Why an Addison-local team matters

On Dallas Water Utilities' hard water, a tankless without a softener does not hit its rated 20-year life — the heat exchanger scales up in 3-4 years and most manufacturer warranties exclude scale damage. Every tankless we install in Addison gets a softener recommendation, and we offer a $50 bundle discount when both are installed together. We also know which 1970s Belt Line townhomes have the gas capacity for a 199k BTU unit and which need an Atmos service upgrade first.

Why choose Belt Line Plumbing for tankless water heater installation

⭐ 4.9 · 412+ reviews18+ years serving AddisonLicensed & insured30-min Tollway response

We install Rinnai, Navien, AND Noritz

Not a single-brand dealership. We recommend based on your gas capacity, venting path, and recirculation preference — not on which brand pays us the most.

Gas-line math done before quoting

We never quote a tankless without checking your gas line capacity first. Undersized gas is the #1 cause of early tankless failure in DFW.

Softener bundle discount

$50 off the softener when installed with a new tankless. Protects your 20-year warranty on Dallas hard water.

Annual descale service plan

Dallas Water Utilities will scale any tankless. We offer a maintenance plan that includes the annual flush and manufacturer-required inspection to keep warranty intact.

A finished tankless water heater installation job in Addison — pressure-tested, cleaned up, warrantied in writing.

Tankless Water Heater Installation — service area

We install tankless water heaters across Addison (heavy demand from 1970s Belt Line townhomes with limited utility-closet space), Farmers Branch, Carrollton, University Park, Highland Park, and every new-build subdivision in Frisco, Prosper, and Celina where tankless is now standard. We dispatch from our Keller Springs Rd HQ inside Addison, so response is genuinely fast in the Tollway corridor and same-day across Dallas County, plus Collin and Denton counties north to Frisco and beyond.

Tankless in Dallas County →Tankless in Dallas →Tankless in Carrollton →Tankless in Farmers Branch →Tankless in Hebron →Tankless in Plano →Tankless in Frisco →Tankless in The Colony →

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Tankless Water Heater Installation — Where We Serve

Belt Line Plumbing dispatches tankless water heater installation trucks across the Dallas North Tollway corridor. Top cities:

Dallas County Dallas Carrollton Farmers Branch Hebron Plano Frisco The Colony View all →

Tankless Water Heater Installation — FAQs

DFW tankless installs typically run $2,500-$5,500 depending on unit size, whether the gas line needs upsizing, venting path, and whether a softener is bundled. The number for your home is quoted flat, in writing, after an on-site demand audit — never over the phone sight-unseen.

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Water Heater Repair vs. Replace: Cost Guide for Addison Homeowners

When is repairing your water heater worth it, and when should you replace? Real cost ranges for Addison, plus the Dallas hard water factor.

Local-Specific

Hard Water in Dallas County: What Dallas Water Utilities Supply Does to Pipes

Dallas Water Utilities delivers hard water in Addison — 8–11 grains per gallon. What that does to your heater, tankless, and dishwasher.

Prevention

Flush Your Water Heater Yearly — Especially on Dallas Hard Water

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