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Water Heater Recovery Rate Calculator
Recovery in gallons per hour at the rise you actually have, the recovery GPH at the 90 F rating basis, and an estimated first-hour...
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Water heating calculators
Tank size, tankless GPM, recovery, UEF running cost, and payback — each with visible math.
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Tankless Water Heater Size Calculator
Size simultaneous GPM and heat input so the coldest incoming water still gets hot, then screen the candidate unit's published rating.
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Water Heater Size Calculator (First-Hour Rating)
Size a tank from the hot water the fixtures draw in the busiest hour, then screen it against the nameplate first-hour rating.
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Wire Ampacity Calculator (NEC Table 310.16)
Allowable ampacity by conductor size, material and termination column, with the adjustment factors you applied.
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Electrical Panel Capacity Calculator
Spare service capacity after adding a water heater, with the 125 percent continuous factor and the next standard service rating.
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Voltage Drop Calculator
Voltage drop in volts and percent for a run, from the circular-mil formula with NEC Chapter 9 Table 8 areas.
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Water Heater Breaker Size Calculator
Standard breaker rating from the load, checked against the NEC 310.16 ampacity of the conductor and the 240.4(D) small-conductor limits.
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Home Electrical Load Calculator (NEC 220.82)
Dwelling service load by the NEC 220.82 optional method, from floor area, circuits, fixed appliances and HVAC.
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Appliance Energy Cost Calculator
Rank appliances by what they cost to run, with duty cycle, standby draw and each one's share of the bill.
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Electricity Bill Estimator
Turn a metered month into a monthly and annual bill, the effective all-in rate, and the water heater's share of it.
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