Hot water a business depends on
Commercial water heater repair and replacement in Houston
A restaurant without hot water cannot wash dishes, and a building full of tenants without it fills your voicemail by morning. When the commercial heater quits, the clock starts right away.
- We answer 24/7, including weekends and holidays
- Out of South Belt for southeast Houston businesses
- High-input tanks, tankless racks and booster heaters
Updated October 2026
Short answer
Commercial water heater service in Houston covers high-input gas tanks, multi-unit tankless racks and the booster heaters that bring dish machine water up to sanitizing temperature. We diagnose ignition, burner, control and scale problems on site, and when a tank has failed we size the replacement to your actual peak demand, not just the old label.
What to watch for
Signs a commercial heater is falling behind
Water goes lukewarm at peak hours
The heater is undersized, scaled up, or one unit in a rack has failed.
Dish machine rinse temperature drops
The booster heater element or thermostat is failing.
Rumbling or popping from the tank
Sediment has built up in the bottom and is overheating.
Error codes on a tankless unit
Often scale, a flow sensor fault or a venting problem.
Water around the base
A relief valve discharge, a loose fitting or a failed tank.
Pilot or burner keeps going out
A flame sensor, thermocouple or venting issue.
The job
Why commercial heaters fail differently than home units
A commercial water heater works much harder than a residential tank. A restaurant can drain and refill it many times a day, and a heater serving an apartment building sees heavy morning and evening peaks. More firing cycles mean more wear on igniters, gas valves and flame sensors, and more water means more sediment and scale settling in the bottom of the tank or the heat exchanger.
We start by finding out whether the problem is no heat, not enough heat or a leak. No heat usually points to ignition, venting or gas supply. Not enough heat often means a failed element or burner, a broken dip tube, heavy scale, or a heater that was undersized from the start. A leaking tank body cannot be fixed. If the building's demand has changed, we will talk about sizing before we replace anything. For general building plumbing beyond the heater, see our commercial plumbing work.
The versions we see most
High-input commercial tanks
These are the large gas or electric tanks in restaurant back rooms, laundromats and apartment mechanical closets. Owners usually call because the water runs lukewarm by midday, the burner keeps cycling off, or water is pooling under the tank. We check the gas valve, igniter, flame sensor, thermocouple or control board, venting and flue draft, and on electric units the elements and thermostats. Sediment is a big cause of noise and lost capacity, so flushing is part of most visits. When the tank itself is leaking, we plan a replacement and line up the right size, venting and gas supply, often with a gas line upgrade if the input goes up.
Commercial tankless racks
Some businesses use several tankless units linked together on a rack, sharing the load. When one unit fails, the others carry on but the system falls behind at peak times, which shows up as water going cold during the lunch rush or morning showers. We read error codes, check each unit's flow sensor, gas pressure and venting, and clean scaled heat exchangers by descaling the system with a pump and solution. A rack that keeps throwing scale errors is a sign the water needs treatment. We can add a scale filter or talk about a water softener to protect the units.
Booster heaters
A high-temperature dish machine needs final rinse water much hotter than the building supply, and a booster heater makes up the difference. When the booster fails, the machine either stops or the rinse temperature falls below what the health inspector wants to see. Common causes are burned-out elements, failed thermostats or high-limit switches, and scale packed around the elements. We test each part, replace what has failed and flush the tank. When a booster is old and scaled badly, replacing it usually costs less over time than repeated repairs. We coordinate with your dish machine service company when the problem sits on the machine side.
Step by step
From a cold-water call to hot water back on
Triage by phone
We ask what the heater serves, its age and what is happening, so we bring the right parts.
Diagnose on site
We test ignition, controls, elements, venting and gas supply to find the actual cause.
Restore service
Where possible we repair right away; if a replacement is needed, we tell you how long it will take.
Size the replacement
We check peak demand and fixture count so the new heater fits how you use hot water.
Install and test
The heater is set, vented, connected and run through a full heating cycle.
Local to southeast Houston
Houston water and scale inside commercial heaters
Hardness in Houston's main water system ranged from 43.5 to 229 ppm in the 2025 water quality report, averaging 135.5 ppm. The USGS classifies 121 to 180 ppm as hard and notes that long-term flow of hard water through pipe can cause scale. A commercial heater moves far more water than a home unit, so it collects scale faster. In tankless heat exchangers and booster elements, that scale shows up as error codes, lost temperature and failed parts, which is why flushing schedules matter more here.
Call before it gets worse
We answer 24/7 from South Belt.
Your options
Commercial tank or tankless rack: which fits your business
| Compare | High-input tank | Tankless rack |
|---|---|---|
| Suits | Big draws at once, like a full dish cycle or many showers | Steady demand spread through the day |
| Space needed | A large footprint on the floor | Wall-mounted units, less floor space |
| If one part fails | The whole heater is out until repaired | Other units keep running at reduced capacity |
| Scale sensitivity | Sediment builds in the tank and needs flushing | Heat exchangers scale up and need regular descaling |
| Gas supply and venting | One large burner and flue | Several units with their own vents and higher combined gas demand |
If your demand comes in sharp bursts, a tank or a tank paired with tankless units often works better. If demand is steady and you value backup capacity, a rack makes sense.
Pricing
What sets the cost of commercial water heater work
Commercial heater jobs range from a single part to a full replacement with new venting. These are the main things that change the cost.
Repair or replacement
A failed igniter or element is a part swap. A leaking tank means a new heater.
Heater type and input
High-input gas tanks, tankless racks and boosters each use different parts and labor.
Venting and gas supply
Larger replacements may need a new vent run or a bigger gas line.
Scale buildup
Heavily scaled heat exchangers or tanks take longer to descale or flush.
Access and timing
Tight mechanical rooms and after-hours work change how the job is planned.
Parts availability
Common parts ride on the truck; some commercial controls need to be ordered.
Typical planning range: $3,000 - $8,000 per unit installed for multi-family storage tank systems (tankless commercial $5,000 - $15,000 or more), per AAA Plumbers (Augu). Use it for budgeting; the real number depends on what we find on site.
Brands we service and install
We repair and replace commercial heaters from Rheem, A. O. Smith, Bradford White, Navien and Rinnai, along with the booster heaters behind most dish machines.
- Rheem
- A. O. Smith
- Bradford White
- Navien
- Rinnai
- Noritz
- Kohler
- Moen
- Delta
- American Standard
- Pfister
- InSinkErator
- Uponor
- Watts
Common questions
Commercial Water Heater Service questions from Houston homeowners
Often the same day for repairs, since we carry common parts. If the tank has failed, we can sometimes set a temporary solution while the replacement is sourced.
We look at the fixtures and equipment using hot water, how many run at the same time and your peak hours. The heater should match that peak demand, not just the size of the old unit.
With Houston's hard water, heavy-use tanks and tankless units often need flushing or descaling more than once a year. We can suggest a schedule based on how fast scale builds in yours.
Scale around the elements is the usual cause. If the booster is old and heavily scaled, replacement plus water treatment often costs less than repeated repairs.
Yes. We service central heaters that feed several units as well as individual heaters in each apartment, and we can check every unit during one visit.
Same system, different job
Related plumbing services
- Commercial PlumbingRestrooms, kitchens and tenant spaces kept running for businesses and landlords.
- Water Heater RepairNo hot water, pilot trouble or a leaking valve fixed on tank heaters, gas or electric.
- Tankless Water Heater RepairError codes, cold-water sandwiches and scaled heat exchangers diagnosed and fixed.
- Water Heater Flush & MaintenanceSediment flushed, anode checked and the relief valve tested before trouble starts.
- Gas Line InstallationNew gas runs for ranges, dryers, tankless heaters, generators and outdoor kitchens.
Something leaking right now?
Call any hour. We will help you stop the water first and get a plumber moving.