Introduction to Water Heaters : 1.5 Water Heater Anatomy: Hybrid Water Heaters

 

Basic Structure:

• An electric water heater with a heat pump on top, running solely on electricity.

• Heat pump is the primary heating stage, with electric heating elements activated during high demand.

Water Connections:

• Cold water enters the lower side connection.

• Hot water exits from the upper side connection.

• Additional piping is part of the heat pump system.

Heat Pump Process:

• Hot gas refrigerant from the compressor travels through coils wrapped around the tank, transferring heat to the water.

• After condensing, refrigerant passes through a metering device, absorbing heat from the surrounding air before returning to the compressor.

Efficiency:

• The system is about 15% more efficient than standard electric water heaters.

• In warmer climates, the heat pump can also cool down spaces like a hot garage, further improving efficiency.

Introduction to Water Heaters : 1.4 Water Heater Anatomy: Indirect Water Heaters

 Types of Indirect Water Heaters:

• Storage Type: Includes a tank with a heat exchanger, either a tank-in-tank design or a coil-type heat exchanger inside.

• Instantaneous Type: Uses a flat plate heat exchanger for rapid water heating.

Storage Type Indirect Water Heater:

• Cold potable water enters the tank and absorbs heat from the coil heat exchanger.

• Controlled by a temperature sensor that activates the circulator and boiler when water temperature drops below 120°F.

• Provides a steady supply of hot water, even when the boiler is off.

Instantaneous Type Indirect Water Heater:

• Uses a flat plate heat exchanger where hot boiler water flows through alternating plates, and potable water flows between them.

• Heat is transferred efficiently without mixing the boiler water and potable water.

• The system is designed for maximum efficiency with hot and cold water flowing in opposite directions.

Efficiency:

• Modern high-efficiency boilers (over 90%) paired with indirect-fired water heaters are significantly more efficient than electric or standard gas-fired tank-type heaters.

• These systems, often made with stainless steel, are durable and long-lasting.

Introduction to Water Heaters : 1.3 Water Heater Anatomy: Gas Fired Tankless

 

Vent System:

• Vent Outlet: Located at the top, often with two openings—one for fresh air intake and the other for venting exhaust gases.

Heat Exchanger:

• A coil-type heat exchanger where water spirals through, progressively heating up as indicated by color changes in the piping (blue to red).

Burner Compartment:

• Burner: Controls heat generation.

• Combustion Fan and Gas Inlet: Work together to adjust the firing rate based on demand.

Flow System:

• Cold Water Inlet (blue pipe) and Hot Water Outlet (red pipe) on opposite sides.

• Flow Sensor: Detects water flow and communicates with the onboard computer to adjust the burner’s firing rate based on demand.

• Flow Control Valve: Regulates the water flow to maintain the correct outlet temperature.

Onboard Computer:

• Manages all components and ensures balanced operation, adjusting the burner and flow control valve for optimal performance.

Introduction to Water Heaters : 1.2 Water Heater Anatomy: Electric Tank Type

 

Shared Features:

• Cold Water Inlet: Located on the right side.

• Pressure Relief Valve: Positioned at the top.

Unique Features of Electric Heaters:

• Upper Thermostat: Controls the top half of the heater and the upper heating element.

• Lower Thermostat: Indirectly senses the temperature by pressing against the tank's outer wall and controls the lower heating element.

Dip Tube:

• Directs cold water to the bottom of the tank, preventing it from mixing with hot water at the top.

Tank Structure:

• Glass Lined Steel Tank: The steel tank has a glass lining to prevent rusting.

• Outer Jacket: Wraps around the tank to protect insulation (though some models may not show the insulation visibly).

Anode Rod:

• Crucial for protecting the tank from rust; its role will be discussed further.

Hot Water Outlet:

• Located on the left side.

Introduction to Water Heaters : 1.1 Water Heater Anatomy: Gas Fired Tank Type

 

Water Heater Types:

• Two main categories: Storage type (gas and electric) and Tankless.

Gas Water Heater Anatomy:

• Draft Diverter: Located at the top, connects to flue piping. Allows fresh air to mix with flue gases.

• Cold Water Inlet: Always on the right side.

• Pressure Relief Valve: Located at the top for safety.

• Dip Tube: Directs cold water to the bottom of the tank to avoid mixing with hot water.

Flue Baffle:

• Twisted metal piece inside the flue passage. Slows down flue gases to retain more heat in the water.

Components at the Bottom:

• Drain Valve: For maintenance.

• Gas Burner: Works with the gas valve and thermostat.

• Thermostat: Direct immersion sensor controls water temperature.

Tank Construction:

• Glass Lined Tank: Steel tank with a glass (ceramic/enamel) lining to prevent rusting.

• Foam Insulation: Retains heat within the water heater.

• Metal Jacket: Thin outer layer protecting the insulation.

Anode Rod: Essential for preventing rust; should not be removed.

Hot Water Outlet: Always on the left side.

Plumbing Code Overview : 5. Tests and Inspections

 Importance of Testing and Inspection:

• Plumbing and drainage systems must be inspected and tested before being covered, concealed, or put into service.

Underground Inspection:

• Conducted after excavation and installation of piping, but before backfilling.

• Easier to test and repair leaks before covering the pipes.

Rough-In Inspection:

• Performed on completed portions of sanitary, storm, and water distribution piping after framing, fire blocking, and bracing are in place, but before wall or ceiling installation.

Final Inspection:

• Conducted after the building is complete, with all plumbing fixtures in place and properly connected.

• This inspection ensures the building is ready for occupancy.

pt2.

Sewer System Testing:

• Insert a test plug at the connection to the public sewer.

• Fill the system with water, maintaining at least 10 feet of head pressure for 15 minutes.

Drain Waste and Vent (DWV) System Testing:

• Water Test: Fill each section with water to the highest point, hold for 15 minutes, and inspect for leaks.

• Air Test: Pressurize the system to 5 PSI or 10 inches of mercury, holding for 15 minutes without leaks.

Fixture Traps Testing:

• After installation, fill the traps with water, then test for both water and gas tightness.

• Water Tightness: Fill and drain each fixture to visually inspect for leaks.

• Gas Tightness: Use either a theatrical smoke generator or peppermint oil to detect gas leaks.

Water Supply System Testing:

• Upon completion, test under water pressure at least equal to the system’s working pressure or an air pressure test of no less than 50 PSI for 15 minutes.

• Use proper test gauges with the following increments:

• 0.1 PSI for pressures under 10 PSI.

• 1 PSI for pressures between 10-100 PSI.

• 2 PSI for pressures over 100 PSI.

Plumbing Code Overview : 4. Codes and Natural Disasters

 Earthquake-Prone Areas:

• Plumbing systems must have proper support to prevent rupture during earthquakes.

• Follow the International Building Code for the required supports to minimize the risk of water, fuel, or gas leaks during seismic events.

Flood-Prone Areas:

• Structures in flood hazard areas require special plumbing equipment and piping as per the International Building Code to protect plumbing systems during floods.

• Additional flood-specific codes include sealing potable water wells and securing manhole covers (except those above flood elevation).

• In coastal high hazard areas, plumbing systems should not be installed in walls that are designed to break away during floods.

General Advice:

• Always consult the plumbing code for unique methods and components specific to natural disaster areas.

Plumbing Code Overview : 3. Protection of Pipes and Structural Safety

 Piping Protection:

• The plumbing code specifies methods to protect piping during installation.

• Prevent corrosion by avoiding contact between dissimilar metals using dielectric unions or gaskets.

• Pipes must be properly supported with hangers and suspensions to avoid stress and strain.

Wall and Underground Installations:

• Pipes passing through foundation or masonry walls must be protected with wall sleeves or relieving arches.

• Underground water supply pipes should be installed no less than 12 inches below grade and more than 6 inches below the frost line to prevent freezing and ruptures.

Roof Penetrations:

• Roof joints and vent pipes passing through the roof must be sealed with water-tight materials to prevent leaks.

Structural Integrity:

• Always follow the International Building Code when installing plumbing.

• Avoid cutting, drilling, or altering structural framing, such as roof trusses, to maintain the building's structural safety.

Plumbing Code Overview : 2. Materials and Rodent Proofing

 Plumbing Materials:

• The plumbing code specifies which materials must be used for specific plumbing applications.

• Materials should have the manufacturer's identification stamped on them.

• Installation should follow professional standards and comply with the plumbing code.

Rodent Prevention:

• Plumbing systems must be designed to prevent rodents from entering the building.

• Rodents commonly enter through drain lines, meter boxes, and piping penetrations.

• Key Preventive Measures:

• Install strainer plates on drains with openings no larger than ½ inch.

• Ensure meter boxes are sealed to prevent rodent access near the water supply system.

• Seal gaps around piping penetrations with approved sealing materials, such as caulk, suitable for the application.