What a tankless heater is, and what it asks of your house
A tankless, or demand-type, heater has no storage tank. When a tap opens, a flow sensor starts a gas burner or electric elements that heat the water as it passes through a heat exchanger. Hot water lasts as long as the unit can keep up with the flow.
That design saves floor space and ends the standby heat loss of a full tank. It also moves the work onto the supply lines. A tankless unit draws a large burst of gas or electricity at once, so the house has to be able to deliver it.
Gas or electric tankless, and how they differ
| Feature | Gas tankless | Electric tankless |
|---|---|---|
| Supply needed | Gas line sized to the unit's rated input | Heavy-gauge wiring and large breakers, often several |
| Venting | Sealed vent through a wall or roof | No flue, which allows an indoor spot |
| Output at a 70-degree rise | About 5 gallons per minute | About 2 gallons per minute |
| Best fit | Larger households and multiple showers | Small homes, apartments, or a single sink point-of-use |
The Department of Energy gives these typical figures. A 70 degree rise is commonly achievable at 5 gpm for gas units and 2 gpm for electric ones. That gap explains why whole-house electric tankless units need a strong electrical panel, and why many homes pick gas.
Ready to book tankless water heater? Same-day appointments are offered when the schedule allows.
Call (770) 214-4545Sizing the unit by flow rate and temperature rise
Tankless units are rated by the temperature rise they can deliver at a given flow. The Department of Energy tells you to add up the flow of the fixtures that run at once, such as a shower and a dishwasher. If you do not know a fixture's flow, time how long it takes to fill a bucket for one minute.
Next, subtract the incoming water temperature from the temperature you want. The Department of Energy uses 50 degrees Fahrenheit as the inlet when you do not know it, and 120 degrees as the outlet for most uses, which gives a 70 degree rise. Winter groundwater is colder, so a unit that barely meets the numbers in July may fall short in January.
A plumber does this math with your actual fixtures. If two showers and a washing machine run together, one unit may not cover them, and a second unit or a different plan may be better.
Gas line, venting, and the install itself
A gas tankless often draws more gas at once than the tank it replaces. The existing line has to be checked against the new unit's rated input, and an undersized line is reworked or upsized before the unit goes on the wall. It is worth asking about before you accept a quote, because it can change the scope.
Venting is the second item. Gas units need a sealed, manufacturer-approved vent pipe through the wall or roof. Union City's permit page lists the 2018 International Fuel Gas Code with Georgia amendments, and permit rules vary, so ask Union City Community Development at (770) 515-7920 what a swap requires. The permit is issued to the certified contractor.
Electric units skip the vent and the gas line but ask more of the panel. If the panel is full or old, that upgrade is part of the true cost. For general fixture and rough-in work around the heater, see plumbing installation. If you are comparing against a standard tank, the water heater installation page lays out the planned install day.
Honest trade-offs before you commit
Upfront cost
Tankless units and their installs usually cost more than a tank swap, and the savings arrive slowly through lower operating costs.
Delay and flow limits
The unit takes a moment to fire, and the hot stream can fall off if too many fixtures run at once.
Maintenance
Scale builds inside the heat exchanger, so an annual flush is part of ownership rather than an extra.
Repairs
Parts such as the heat exchanger, flow sensor, and control board are specific to the brand, and repairs on them take a technician who knows the model.
Tankless is a good match for small households that value space, or for homes where a tank will not fit. It is a weaker match for a busy house of five on a tight budget, where a properly sized tank may serve better.
Flushing and descaling, why it matters and how often
Minerals in the water leave scale inside the waterways and on the heat exchanger. Navien says the deposits can erode and clog the heat exchanger, cutting efficiency and flow and leading to early failure. Heavy scale can show up as error codes, noisy firing, and weaker hot water.
Navien recommends descaling at least once a year, and more often with high mineral content, a high temperature setting, or heavy use. Other makers publish their own schedules in the manual, so follow the one printed for your model. Hard water speeds up buildup, so the schedule depends on your water.
The city's water quality report does not publish hardness, so Union City owners cannot look up a number. Test your tap with a hardness kit, and ask the water department at (770) 306-6855 for the report. A high reading is a reason to flush sooner.
| Option | What it involves | Good fit |
|---|---|---|
| Vinegar flush by the owner | White vinegar circulated through the isolation valves with a pump and hoses, then at least 10 minutes of fresh water | Handy owners with the right fittings who follow the manual |
| Professional service | Flush with the correct solution and pump, plus inspection of the filter, burner or elements, and vent | Units under warranty, gas models, or any unit that already shows faults |
Navien notes that improper service could damage the unit and void the warranty, so read the warranty terms before you start. If the unit has no isolation valves, adding them is the first job.
Error codes and shutdowns, what they often point to
Every brand uses its own codes, so the manual or the label inside the front panel is the first reference. Codes commonly point to ignition problems, a blocked vent, low flow, a scaled heat exchanger, or an overheated unit. Writing the code down before you reset the unit helps the technician.
It is safe to check that the gas valve is open, the breaker is on, and the vent is clear of nests or snow. Do not remove the cover or reset a unit that repeats the same code more than once. A heater that keeps locking out is protecting you from a combustion or overheating problem, and the cause should be found first.
Gas smell or carbon monoxide alarm
Leave the house and call 911 or your gas utility from outside. Do not reset the unit or try to relight anything.
If your existing heater is a standard tank and fails, the water heater repair page has the symptom guide.
Union City homes and renters
Union City has about 40.4 percent owner-occupied homes according to Census QuickFacts, so most households rent. A tenant should not install a tankless unit without the owner's approval. A landlord who owns several units may prefer a standard tank for simplicity.
The city buys treated water from Atlanta, which uses chlorine as the disinfectant. The water quality report lists chlorine and other measured items, but not hardness or pH. Your own tap test is the only way to know whether scale will be a minor or major concern for a tankless heater.
What changes the price of a tankless water heater job
Unit type and capacity
Whole-house gas, whole-house electric, and point-of-use units sit in different price brackets.
Gas line and electrical upgrades
An undersized gas line or a full electrical panel adds work before the unit is mounted.
Venting route
A short wall vent is simpler than a long run to the roof, and old flue pipe from a replaced tank may need removal.
Isolation valves and water treatment
Valves for flushing and a scale filter are small additions that make maintenance easier.
Service scope
A flush on an easy-access unit is a short visit. A scaled heat exchanger or failed sensor takes longer and costs more.
Installation and annual service are planned costs, and homeowner insurance usually does not pay them. If a failed connection floods the house, the water damage may be covered as sudden and accidental. Ask your insurer, and ask your landlord if you rent.
A tankless quote depends on the gas, vent, and panel at your address, so we give a clear price before work starts. Want your real number? Call (770) 214-4545.
Common questions about tankless water heater in Union City
Navien recommends at least once a year, and sooner with hard water or heavy use. Check your own manual, since schedules vary by brand.
Household white vinegar is accepted by Navien, followed by at least 10 minutes of fresh water. Follow your manual, because improper service can void the warranty.
The city's water quality report does not list hardness. Use a test kit on your tap, or ask the water department at (770) 306-6855 for the report.
Often the line must be checked against the unit's rated input and sometimes upsized. A plumber measures the run and the load before quoting.
Each brand uses its own codes, so look up your model's manual. Common causes are ignition trouble, a blocked vent, low flow, or scale.
It can when too many fixtures run at once, because flow outruns what the unit can heat. Sizing by gallons per minute and temperature rise prevents it.
The 24/7 line is open for urgent problems, such as a gas smell or a leak. Routine flushing and installs are scheduled, with same-day appointments when available.
Tankless Water Heater across Union City and nearby towns
Tankless installs and service visits reach Union City and nearby Riverdale, College Park, Fairburn, South Fulton, and Palmetto.
Questions about tankless water heater? Call the line and describe what you see.
Call (770) 214-4545