Tankless Water Heater Conversion and Whole-House Water Conditioning in Peoria, AZ

When a homeowner in the Mira Vista at Vistancia neighborhood of Peoria, AZ reached out to address their household water heating and water quality needs, they required two major system upgrades: converting an aging storage tank to a high-efficiency tankless system and installing a comprehensive whole-home water treatment unit.

The homeowner supplied their own unit—a Rinnai CXP199i tankless water heater—and selected the Encore Reveal All-In-One Water Softener + Water Filtration system to handle total household water conditioning. Pridemark Plumbing was brought on site to remove the old equipment, execute the tank-to-tankless structural conversion, hard-pipe the system through the wall, and integrate the filtration unit into the home’s existing 1-inch plumbing loop.

Understanding Hard Water and Water Heating Challenges in Peoria, AZ

To understand why a combined water heater installation and water conditioning upgrade makes sense in central Arizona, it helps to examine the raw supply water entering homes across Maricopa County. Local water utility distribution relies on surface water sourced from the Colorado River and Salt/Verde River basins, supplemented by deep groundwater wells.

Because groundwater and river water percolate through desert rock formations rich in limestone, gypsum, and calcium deposits, the supply delivers a heavy concentration of dissolved minerals, primarily calcium carbonate and magnesium. Water hardness in Peoria often measures between 15 and 25 grains per gallon (GPG), placing local water firmly in the “very hard” category.

How Hard Water Affects Traditional Tank Water Heaters

When untreated hard water enters a conventional tank water heater, thermal processing accelerates a natural chemical reaction. As water heats up, dissolved calcium and magnesium precipitate out of liquid solution and form solid mineral crusts known as scale.

Over time, this scale accumulates along the internal walls of the tank and settles heavily across the bottom, directly above the burner assembly or lower electrical heating element.

• Thermal Insulation Barriers: Mineral scale creates an insulating blanket over heating elements. The heater must run longer and work harder to push thermal energy through inches of hard scale to reach the water, causing energy consumption to rise.
• Overheating and Tank Fatigue: Concentrated heat beneath a layer of scale causes localized overheating on the steel tank bottom. This thermal stress weakens protective glass linings, accelerating internal rust and premature tank failure.
• Sediment Displacement & Popping Sounds: As trapped water underneath scale layers boils, steam bubbles pop through the sediment, creating loud knocking noises and disturbing plumbing lines.
• Restricted Storage Capacity: Inches of heavy mineral buildup physically reduce the usable holding capacity of a standard 40- or 50-gallon tank, leaving less hot water available for domestic household tasks.

The Impact of Disinfectants and Dissolved Chlorine

In addition to mineral hardness, municipal water distribution facilities use chlorine or chloramines to sanitize municipal water lines. While essential for public health, residual disinfectant lingering in tap water creates distinct home maintenance issues.

Chlorine dries out skin and scalp during showers, leaves chemical odors, strips natural oils from hair, and reacts negatively with household soaps. Furthermore, chlorine actively degrades synthetic rubber seals, washer gaskets, and flexible supply connectors throughout the home’s plumbing network, accelerating minor leaks behind toilets and under sinks.

Technical Considerations: Tank-to-Tankless Conversions

Upgrading from a traditional storage tank to a high-capacity tankless water heater like the Rinnai CXP199i is not a simple direct swap. Standard storage tanks maintain a reserve of water kept hot continuously using a relatively low thermal input (typically 36,000 to 40,000 BTU/h for standard residential natural gas units).

By contrast, a tankless unit heats cold water instantaneously on demand as it flows through a compact heat exchanger. Achieving instant heating requires a dramatically higher thermal input—in this case, up to 199,000 BTU/h.

Critical Elements of a Tankless Conversion

1. Gas Line Capacity: Because thermal demand increases significantly during flow, gas piping sizing must be evaluated to ensure adequate gas pressure reaches the unit during full load operation without starving other domestic gas appliances.
2. Physical Location and Structural Support: Wall-mounted units require structural framing support. Mounting bracketry must be secured properly to withstand vibration and operational pipe strain.
3. Plumbing Configuration: Storage tanks connect to supply lines above the unit. Tankless models feature bottom-mounted connections. Adapting existing lines requires opening wall sections, rerouting supply headers, and transitioning materials safely.
4. Combustion Venting: High-efficiency condensing tankless systems extract maximum heat from combustion gases. As exhaust gases cool, they form moisture and cannot be routed into standard metal B-vent chimneys. Dedicated exhaust and air intake pipes made from approved polymer materials must be run directly through exterior walls or roof lines.
5. Condensate Management: Condensing heat exchangers produce acidic water condensate during operation. A dedicated condensate drain line must be safely piped to an approved discharge location.

Mechanics of Whole-House Water Softening and Filtration

While a tankless water heater eliminates standby energy loss and delivers continuous hot water, protecting that unit and household plumbing from Arizona’s mineral-dense water requires complete water treatment and purification.

The system selected for this job—the Encore Reveal All-In-One Water Softener + Water Filtration unit—combines ion-exchange water softening with multi-stage chemical filtration inside a single system architecture.

The Physics of Ion Exchange Softening

Water softening relies on a process known as ion exchange. Inside the primary vessel, millions of tiny resin spheres carry negative electrical charges held in balance by weakly bonded sodium or potassium ions. As hard water flows past these resin beads, the stronger electrical charge of dissolved calcium and magnesium ions attracts them to the resin surface. The resin captures the hardness minerals and releases a neutral amount of sodium or potassium into the water stream.

The durability of softening resin depends on its chemical cross-linking. Standard residential water softeners typically use resin with an 8% cross-link structure. Chlorine present in municipal water breaks down 8% cross-linking over time, causing resin beads to swell, fracture, and turn into mush, which restricts household water flow.

The Encore Reveal unit uses commercial-grade 10% cross-linked resin, providing superior structural resistance against oxidation and chemical degradation caused by municipal chlorine.

Dual-Stage Media Filtration

Beyond softening, whole-house filtration cleanses water of municipal additives and dissolved heavy metals using two distinct media types:

• Catalytic Carbon Foam Cubes: Unlike standard granular carbon that can settle or form channels where water passes through uncleaned, carbon foam cubes force water to pass through dense structural pores. This design maximizes surface contact time to remove chlorine, chloramines, synthetic chemicals, and unpleasant odors.
• Reticulated KDF Cubes: Kinetic Degradation Fluxion (KDF) uses high-purity copper and zinc formulations. Through an oxidation-reduction (redox) process, KDF exchanges electrons with dissolved contaminants, transforming heavy metals (such as lead and mercury) into harmless soluble compounds while creating an environment that inhibits bacterial and algal growth inside the media bed.

Efficient Regeneration Cycles

To maintain performance, the system periodically regenerates by drawing a salt-water solution from its 15×17 brine tank (equipped with a safety float valve to prevent overflow). Modern high-efficiency systems utilize up-flow washing and proportional brining options.

Rather than flushing from top to bottom on a basic clock timer, up-flow regeneration directs brine upward through the bottom of the resin bed, working through the least exhausted resin first. Combined with proportional brining—which calculates the exact salt needed based on actual water used—these features save between 30% and 70% in salt and wastewater compared to basic legacy systems.

Project Execution: Specific Work Performed in Peoria, AZ

When the team arrived at the home in the Mira Vista at Vistancia neighborhood of Peoria, AZ 85383, the project was split into two distinct mechanical phases: the tank-to-tankless water heater conversion and the whole-home water treatment system integration.

Phase 1: Storage Tank Removal and Tankless Conversion

Our technician began by disconnecting, draining, and removing the homeowner’s existing floor-standing tank water heater from the garage utility space, taking care to haul away the old tank cleanly.

Once the area was cleared, work commenced on converting the space for the customer-supplied Rinnai CXP199i unit:

• Structural Wall Mounting: Secured heavy-duty mounting bracketry directly into structural wall framing to support the wall-hung Rinnai chassis.
• Piping Infrastructure: Opened the wall cavity to reroute domestic supply lines. The technician hard-piped the cold inlet and hot outlet lines through the wall using rigid copper pipe, extending PEX piping behind the wall to join seamlessly into the home’s water distribution headers.
• Gas Line Connection: Made dedicated gas supply connections common to a standard 199,000 BTU/h tankless installation, verifying proper pipe sizing and gas tight seals.
• Venting & Condensate Run: Installed dedicated intake and exhaust venting through the exterior wall envelope to support high-efficiency combustion. A dedicated condensate line was installed and routed safely to manage normal moisture output.

Phase 2: Whole-Home Water Treatment Installation

With the tankless conversion completed, attention turned to installing the customer’s Encore Reveal All-In-One Water Softener + Water Filtration system.

• Plumbing Loop Connection: Located the home’s existing dedicated 1-inch plumbing loop. The system was plumbed directly into this pre-plumbed loop to ensure all domestic water entering the house undergoes softening and filtration before distribution.
• Brine Tank & Vessel Setup: Positioned the 15×17 brine tank adjacent to the main tank vessel, ensuring the integrated safety float valve was balanced to prevent overfilling.
• Protective Covering: Installed a heavy-duty black neoprene cover over the main mineral tank to protect the vessel shell from physical wear and control exterior surface condensation.
• System Programming & Commissioning: Programmed the digital valve controller for proportional brining and up-flow regeneration based on local grain hardness parameters, flushed the media beds, and leak-tested all mechanical joints.

Long-Term Benefits of Combined System Upgrades

Combining a tankless water heater with a complete water softener and filtration system provides measurable operational advantages for home infrastructure.

Continuous Hot Water Delivery

Unlike traditional storage tanks that exhaust their hot water supply during back-to-back usage, the Rinnai CXP199i delivers continuous hot water on demand. Multi-bath households can run showers and laundry concurrently without running out of hot water.

Extended Appliance and Fixture Lifespan

Removing mineral hardness prevents calcium scale from accumulating inside internal components. Dishwashers, washing machines, shower cartridges, and the copper heat exchanger inside the newly installed tankless unit remain free of scale. Eliminating hard mineral crust protects heating elements, preserves water flow rates, and prevents valve seizure across household plumbing.

Protection Against Chemical Degradation

Filtering out chlorine and heavy metals protects internal plumbing seals, rubber flappers, and supply flex lines throughout the home. Furthermore, removing chlorine prevents chemical bath skin irritation and eliminates chemical odors at household taps.

Operational Efficiency and Salt Savings

The high-efficiency design of the Encore Reveal system’s up-flow regeneration and 10% cross-linked resin reduces maintenance overhead. Homeowners use up to 70% less salt and waste significantly less water during regeneration cycles compared to older clock-timer softeners.

Why Professional Execution Matters

Modern residential plumbing involves precise technical standards. High-capacity gas appliances like tankless water heaters require strict adherence to fuel supply calculations, structural mounting practices, and combustion venting codes. Improper venting or undersized gas supply lines can cause incomplete combustion, shortened equipment lifespan, or safety hazards.

Similarly, introducing filtration systems onto existing main water loops requires sound joining methods, appropriate material transitions between copper and PEX, and proper calibration of valve controls. Working with a qualified plumbing contractor ensures system installations comply with local Peoria codes, protect system warranties, and keep home water distribution reliable for years to come.

Whether you need routine maintenance, an equipment evaluation, or custom system upgrades, exploring our broader service area coverage or reviewing our frequently asked questions can help you plan your next home project. When you are ready to evaluate your home’s water quality or water heater performance, feel free to contact us directly to discuss your options.