Explore your water heater
Choose electric or gas, then tap a number or select a part to see what it does and what to check.

Illustrated cutaway for identification. Wiring and installation details are omitted.
See all 15 labeled parts
1. Cold inlet & dip tube
Incoming cold water travels down the dip tube toward the bottom of the tank.
Replacement dip tubes are model-specific; confirm the heater model and manufacturer part number.
A closer look at the parts
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2. Hot-water outlet
Heated water leaves through the outlet near the top of the tank.
Match the connection size, material and temperature rating.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
¾-inch FIP × ¾-inch solder; confirm approved connection method.
View on Amazon ↗3. Cold-water shutoff
This valve stops new cold water entering the heater.
Shutting the supply does not remove water already stored in a leaking tank.
A closer look at the parts
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Push-to-connect valve for listed compatible tubing; check heater instructions.
View on Amazon ↗4. Expansion tank
A potable-water expansion tank provides space for water to expand as it heats in a closed system.
Tank size, air charge, location and independent support must suit the system.
A closer look at the parts
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Potable-water expansion tank; size and precharge must suit the system.
View on Amazon ↗5. Dielectric connections
Dielectric unions or approved connectors help separate dissimilar metals at the water connections.
Use the connection method specified for the heater; built-in dielectric nipples and approved connectors vary.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
¾-inch FIP × ¾-inch solder. Not required with every connection design.
View on Amazon ↗6. T&P relief valve & discharge
This safety valve responds to excessive temperature or pressure. Its discharge pipe carries released hot water to an approved termination.
Never cap the valve or discharge pipe. A plumber should identify why it is discharging.
A closer look at the parts
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Extended probe; a plumber must match pressure, temperature and capacity ratings.
View on Amazon ↗7. Anode rod
A sacrificial anode helps protect the steel tank from internal corrosion.
Match the rod material, thread, length and available overhead clearance to the heater.
A closer look at the parts
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Nipple-style connection; match the exact heater and installation clearance.
View on Amazon ↗8. Tank drain valve
The drain valve connects to the tank near its base for draining and maintenance.
Water can be scalding. Valve length, thread and installation must match the heater.
A closer look at the parts
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Straight drain valve; check thread, length and heater compatibility.
View on Amazon ↗9. Drain pan
A pan catches some leakage beneath the tank and directs it toward its drain connection.
Choose the correct diameter, depth and material. A pan cannot contain every leak.
A closer look at the parts
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For suitable electric-heater applications only; verify required clearance and drain connection.
View on Amazon ↗10. Pan drain
This separate pipe carries water away from the drain pan.
It is separate from the tank drain valve and the T&P discharge; routing and termination require correct installation.
Get help identifying the right part →11. Upper heating element
The upper immersion element heats water near the top of a conventional two-element electric heater.
Match voltage, wattage, mounting style and element length. Electrical servicing requires power isolation and verification.
A closer look at the parts
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4500 W, 240 V, screw-in low-watt-density element; match the heater label.
View on Amazon ↗12. Upper thermostat & high limit
The upper thermostat controls heating near the top; the high-limit device interrupts power if temperature becomes excessive.
A tripped high limit needs diagnosis. Match the exact control and wiring arrangement.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
Apcom-style kit with thermostats and elements; confirm all specifications before ordering.
View on Amazon ↗13. Lower heating element
The lower element heats the lower portion of the tank. Many conventional units operate one element at a time.
Match the heater label and approved replacement part; do not assume upper and lower components are identical.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
4500 W, 240 V, screw-in low-watt-density element; match length and mounting.
View on Amazon ↗14. Lower thermostat
The lower thermostat responds to tank temperature and controls the lower heating cycle.
Do not remove covers or touch wiring with power on. Diagnosis should come before replacing parts.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
Apcom-style lower control; verify model and wiring compatibility.
View on Amazon ↗15. Electrical junction box
The power supply connects to the heater at its electrical junction box.
Circuit, grounding and wiring requirements depend on the heater. The drawing omits wiring details.
Get help identifying the right part →
Illustrated cutaway for identification. Power-vent, direct-vent and condensing models differ.
See all 17 labeled parts
1. Cold inlet & dip tube
Incoming cold water travels down the dip tube toward the bottom of the tank.
Replacement dip tubes are model-specific; confirm the heater model and manufacturer part number.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
2. Hot-water outlet
Heated water leaves through the outlet near the top of the tank.
Match the connection size, material and temperature rating.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
¾-inch FIP × ¾-inch solder; confirm approved connection method.
View on Amazon ↗3. Cold-water shutoff
This valve stops new cold water entering the heater.
Shutting the supply does not remove water already stored in a leaking tank.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
Push-to-connect valve for listed compatible tubing; check heater instructions.
View on Amazon ↗4. Expansion tank
A potable-water expansion tank provides space for water to expand as it heats in a closed system.
Tank size, air charge, location and independent support must suit the system.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
Potable-water expansion tank; size and precharge must suit the system.
View on Amazon ↗5. Dielectric connections
Dielectric unions or approved connectors help separate dissimilar metals at the water connections.
Use the connection method specified for the heater; built-in dielectric nipples and approved connectors vary.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
¾-inch FIP × ¾-inch solder. Not required with every connection design.
View on Amazon ↗6. T&P relief valve & discharge
This safety valve responds to excessive temperature or pressure. Its discharge pipe carries released hot water to an approved termination.
Never cap the valve or discharge pipe. A plumber should identify why it is discharging.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
Extended probe; a plumber must match pressure, temperature and capacity ratings.
View on Amazon ↗7. Anode rod
A sacrificial anode helps protect the steel tank from internal corrosion.
Match the rod material, thread, length and available overhead clearance to the heater.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
Nipple-style connection; match the exact heater and installation clearance.
View on Amazon ↗8. Tank drain valve
The drain valve connects to the tank near its base for draining and maintenance.
Water can be scalding. Valve length, thread and installation must match the heater.
A closer look at the parts
Paid links: Sergeant Plumber Corp. may earn a commission at no additional cost to you.
Straight drain valve; check thread, length and heater compatibility.
View on Amazon ↗9. Drain pan
A pan catches some leakage beneath the tank and directs it toward its drain connection.
Choose the correct diameter, depth and material. A pan cannot contain every leak.
Get help identifying the right part →10. Pan drain
This separate pipe carries water away from the drain pan.
It is separate from the tank drain valve and the T&P discharge; routing and termination require correct installation.
Get help identifying the right part →11. Burner assembly
The burner heats the base of the tank from a separate combustion chamber below the stored water.
Burner and orifice selection depend on the exact heater and fuel. Gas service requires qualified diagnosis.
Get help identifying the right part →12. Gas control & thermostat
The gas control regulates fuel to the burner in response to water temperature and the safety controls.
Replacement gas controls are model- and fuel-specific; similar appearance does not establish compatibility.
Get help identifying the right part →13. Pilot / ignition & flame sensing
The ignition and flame-sensing components establish and monitor burner operation. Designs vary.
Some heaters have standing pilots; others use electronic ignition. Use the exact manufacturer assembly.
Get help identifying the right part →14. Flue & internal baffle
Combustion gases rise through a sealed flue inside the tank. The internal baffle guides the gases and aids heat transfer.
The flue separates combustion gases from the water. Venting problems need prompt professional assessment.
Get help identifying the right part →15. Draft hood & vent
This conventional atmospheric-vent example has a draft hood above the tank leading to the vent.
Power-vent, direct-vent and condensing gas heaters use different systems. Use the specified draft hood and vent design.
Get help identifying the right part →16. Manual gas shutoff
A separate manual gas valve controls fuel supply to the heater.
If you smell gas, leave the area and contact the gas utility or emergency services from a safe location.
Get help identifying the right part →17. Sediment trap
A capped collection leg in the gas piping helps keep debris from entering the gas control.
Location and assembly must follow the heater instructions and applicable requirements.
Get help identifying the right part →Professional Water Heater Services
A dependable water heater is essential for bathing, cleaning, cooking, and everyday comfort. Sergeant Plumber Corp. provides professional water-heater diagnosis, repair, replacement, and maintenance services in The Colony and surrounding North Texas communities.
Your technician will inspect the accessible water heater, discuss the symptoms you have noticed, and evaluate the unit’s condition, installation, and safety components. After the evaluation, the findings and available repair or replacement options will be explained. Upfront pricing will be provided before authorized work begins.
Water Heater Repair
Water heaters may stop heating, recover slowly, leak, make unusual noises, or produce inconsistent water temperatures. We will evaluate the accessible components, explain the likely cause, and determine whether repair is an appropriate option. Repair recommendations will depend on the unit’s type, age, condition, and available replacement parts.
Water Heater Replacement
Replacement may be recommended when the tank is leaking, the unit is extensively deteriorated, repairs are no longer practical, or the existing water heater cannot reliably meet the household’s needs. We will explain the available gas or electric replacement options, installation requirements, and upfront pricing before work begins.
Maintenance & Safety
Water-heater maintenance and safety work may include flushing sediment, inspecting accessible connections, evaluating the shutoff valve, drain pan, discharge piping, expansion tank, venting, and other installation components. Older or deteriorated units will be evaluated before flushing because maintenance can sometimes reveal existing leaks or weakened components.
Signs Your Water Heater May Need Service
Water heater problems can develop gradually or occur without warning.
A professional water heater evaluation may be recommended if you notice:
- No hot water or an insufficient supply of hot water
- Water takes longer than usual to heat or recover
- Water temperature fluctuates or becomes excessively hot
- Popping, rumbling, crackling, or other unusual noises
- Rusty, discolored, or unpleasant-smelling hot water
- Moisture, dripping, or pooling water around the unit or its connections
- Visible corrosion on the tank, valves, piping, or fittings
- Frequent pilot, ignition, thermostat, or electrical problems
What to Expect During Water Heater Service
1. Initial Assessment and Diagnosis
Your technician will discuss the symptoms you have noticed and inspect the accessible water heater, connections, controls, and installation components. The applicable service or diagnostic fee will be explained before the appointment is scheduled.
2. Findings and Upfront Options
After the evaluation, the findings and whether repair, maintenance, or replacement appears appropriate will be explained. Any visible installation or safety concerns that may affect the recommended work will also be reviewed. Pricing will be provided before authorized work begins.
3. Approved Work and Verification
Approved work will be completed using the appropriate parts, materials, and installation method. When applicable, required permits and inspections will be coordinated. The water heater and affected connections will be tested for proper operation before the service is considered complete.
Water Heater Questions Before You Book
Do you service conventional gas and electric water heaters?
Yes. Conventional water heaters store hot water in a tank. We diagnose, repair, replace, and maintain gas and electric units, with recommendations based on the equipment and its installation.
What does a water-heater expansion tank do?
It provides space for water to expand as it heats in a closed plumbing system, helping control the resulting pressure increase. We evaluate the expansion tank and related installation components as part of the service assessment; the appropriate solution depends on your system.
Does a leak mean I need a new water heater?
The source matters: water may be at a connection or coming through the tank itself. If water is leaking through the tank body, the tank generally cannot be repaired and replacement is usually required. An evaluation helps determine which condition applies.
What affects water heater repair or replacement cost?
Water heater repair and replacement requirements vary by unit and property. The unit’s age, condition, fuel type, model, parts availability, location, accessibility, venting, utility connections, drainage, and applicable permit or installation requirements can affect the scope of work. We explain the findings and provide upfront pricing before authorized work begins.
Should an older water heater be flushed?
Flushing or servicing an older or deteriorated unit may reveal existing leaks or weakened components. We evaluate its condition first and discuss visible concerns, available options, and any additional work or upgrades before proceeding beyond the authorized scope.
Need Water Heater Repair or Replacement?
Tell us whether you have no hot water, a leak, or another symptom. If known, include the heater’s brand, fuel type, approximate age, and location so we can prepare for your service request.
Call, text, or request service to discuss the symptoms and schedule an evaluation.
