Dehumidifier Replacement Calculator

This calculator weighs keeping your dehumidifier against replacing it. Describe the old unit by picking its model from the ENERGY STAR lists, by the year it was made and its capacity, or from its capacity and efficiency. Then pick the new model and enter how many hours a year the old one runs and what you pay for electricity. It works out the water removed, each unit's yearly energy use and cost, the yearly saving, the net cost of the new unit, the paybacks, and the cost over the years you choose of keeping the old unit, replacing it now, or replacing it when it wears out.

Model figures come from federal sources only: the ENERGY STAR certified and historical lists published by the EPA, and the DOE test procedure and efficiency standards. Default electricity prices come from the EIA. You set the price of the new unit; the opening example uses an illustrative one, not a quote or a current price.

Purpose and model boundary

This calculator compares two ways forward for a household dehumidifier: keep the unit you have, or replace it with a new one. It works out how much water the old unit removes in the hours you run it, the electricity each unit needs to remove that same water at its rated efficiency, prices it at your electricity rate, and sets the yearly saving against what the new unit costs. Over the number of years you choose, it compares keeping the old unit, replacing it now and, when you say how many years the old unit has left, replacing it when it wears out.

Every figure on this page is computed by the spreadsheet; the page adds nothing to it. The model covers running cost and purchase cost only. It does not judge performance, noise, size or reliability, and it does not price financing, warranties or your own time.

Inputs and units

• The old dehumidifier, described in one of four ways:
  • a model from the ENERGY STAR historical lists (Versions 3, 4 and 5);
  • a model from the current ENERGY STAR list;
  • the year it was made, its class (portable or whole-home) and its capacity in pints a day, plus the case volume of a whole-home unit made from 2019: the calculator then uses the lowest efficiency the federal standard allowed for that year and size;
  • manual entry: its capacity in pints a day, its efficiency in liters per kWh and the rating basis (IEF for labels from June 2019, EF before, or Unknown, where it starts).
• Type: Portable or Whole-home, for each unit. For a listed model, choose the type first, then pick the model from that type's list. Each entry reads "Brand | Model number", exactly as ENERGY STAR lists it.
• The new dehumidifier: a model from the current ENERGY STAR list, or manual entry as for the old unit, and its price, more than $0 and at most $10,000. The price is always yours to set; the examples use round illustrative prices, not quotes.
• Use: the hours a year your current dehumidifier runs removing water, 0 to 8,760. The default is 1,095, the hours the DOE test procedure assumes.
• Electricity price, optional: the state, which sets the default price, or your own price in dollars per kWh.
• Purchase and upkeep: installation, removal and disposal of the old unit, sales tax on the price, verified rebates, the sale or scrap value of the old unit, and yearly upkeep for each unit. Each is optional and counts as zero when left blank.
• The comparison: the years to compare (1 to 30), the yearly change in electricity prices, the discount rate, and, optionally, the years the old unit has left and the expected life of the new unit.

Capacity is in US pints a day (a US pint is 0.473176473 liters), efficiency in liters per kWh, energy in kWh a year and money in dollars.

Governing relationships

The water you remove. The old unit's capacity in liters a day × the hours it runs ÷ 24 gives the water it removes in a year. The calculator assumes the new unit removes the same water.

Energy. Each unit's yearly kWh is that water ÷ its efficiency in liters per kWh. For the old unit this is its capacity ÷ its efficiency × its hours. The new unit runs water × 24 ÷ its capacity hours; if that is more than 8,760 hours a year, the new unit is too small for the load, and the status says so.

Two test procedures. Units listed before the Version 5 list are rated by energy factor (EF) under DOE Appendix X, with capacity measured at 80 °F; Version 5 and current units by integrated energy factor (IEF) under Appendix X1, at 65 °F, which gives a lower capacity for the same unit. When the old and new units are rated on different bases, the old unit's energy, and the saving, are probably understated, and the status says so.

A unit described by the year it was made.

• No DOE study gives the typical efficiency of dehumidifiers by year made, so the calculator uses the lowest efficiency the federal standard allowed for that year and capacity band (10 CFR 430.32(v)): minimum EF from 2007-10-01 and 2012-10-01, minimum IEF from 2019-06-13. That is the most energy such a unit could use: your unit may use less, and the saving may be overstated.
• A year in which the standard changed part-way uses the standard in force on 1 January of that year. A unit made before 2008 is entered manually: there was no federal limit before 2007-10-01.

Yearly cost. For each dehumidifier, the yearly running cost is its yearly kWh times the electricity price; adding yearly upkeep gives its yearly cost, and the yearly saving is the old dehumidifier's yearly cost less the new one's.

Electricity price. Your own price, when you enter one, is used; otherwise the average residential price for the state you choose.

Purchase cost. The capital cost is the price × (1 + sales tax rate) + installation − rebates. The net initial cost adds removal and disposal and takes off the old unit's sale value.

Payback. Simple payback is the net initial cost ÷ the first year's saving, when the saving is positive; otherwise there is no payback. Discounted payback is the first year in which the cumulative discounted net benefit of replacing now reaches zero within the years compared.

The three paths over the years compared. Electricity prices change each year by the rate you enter; upkeep stays flat; costs fall at the end of each year and are discounted at your rate.

• Keep: the old unit's yearly cost every year.
• Replace now: the net initial cost today, then the new unit's yearly cost, less the value left in the new unit at the end.
• Replace at end of life (when you enter the years the old unit has left and they are fewer than the years compared): the old unit's yearly cost until it fails, then the capital cost and disposal in that year, then the new unit's yearly cost, less the value left in the new unit at the end.

The value left in the new unit at the end is its capital cost × the share of its expected life still remaining, on a straight line; with no expected life entered, no value is counted. The net present value of replacing now is the present cost of keeping less the present cost of replacing now: positive means replacing now costs less.

Calculation sequence

The spreadsheet first finds each unit's rated figure from the list, the federal standard for the year made or your entries, and checks the inputs. It then reduces each unit to a yearly energy figure that scales with your use, and from it computes the yearly kWh, the yearly costs and the saving. The purchase cost, the paybacks, the present values of the three paths and the year-by-year cash flow follow. The sensitivity table uses the same per-unit figures, so it cannot disagree with the main result. A block of consistency checks, including that the discounted cash flow reaches the same net present value as the closed-form formula, runs before the status is returned.

Outputs and interpretation

The headline is the yearly saving from replacing the old dehumidifier, with the simple payback and the net present value of replacing now. For each unit the results give its rated figure, its yearly kWh, and its yearly energy, upkeep and total cost, with the electricity price actually used and a note on where it came from. The decision results give the net initial cost, the discounted payback year, the total and present cost of keeping, of replacing now and of replacing at end of life, and a plain verdict on each.

The results also give the water the old unit removes in a year, in pints, and the hours the new unit needs to remove it.

The cash-flow table shows each year from 0 to the years compared: the cost of each path, the net benefit of replacing now, and its cumulative, discounted and cumulative discounted values. The sensitivity table shows the yearly saving at 250, 500, 750, 1,095, 1,500, 2,190, 4,380 and 8,760 hours a year, and at 0.5, 0.75, 1, 1.25 and 1.5 times the electricity price used.

A model card beside each pick shows the model's type, capacity, efficiency and its rating basis, and the year it was listed or became available.

The first chart, “Cumulative net benefit of replacing now, by year”, shows Undiscounted and Discounted by year. The second chart, “Cost over the years compared”, shows Total and Present value by option. The third chart, “Running cost in year 1”, shows Electricity and Upkeep by unit, stacked.

Validation and status logic

The workbook returns one status, chosen in this order: NOT VALID, then CHECK, then OK.

• NOT VALID names the first problem: a source that is not one of its options; a listed model that is not in its list or whose type differs from the type chosen, or, for a unit described by the year made, no class or year (before 2008); a capacity missing or outside 0 to 300 pints a day, a whole-home case volume missing or outside 0 to 50 cubic feet, or no federal band for them; a manual capacity outside 0 to 300 pints a day or a manual efficiency outside 0 to 10 liters per kWh; a manual rating basis that is not one of its options; an upkeep figure outside 0 to $5,000 a year; hours a year missing or outside 0 to 8,760; no electricity price, or your own price outside $0.01 to $2.00 per kWh; a price for the new unit that is missing, not above $0 or above $10,000; another money or rate input outside its range; years to compare that are not a whole number from 1 to 30, or a growth or discount rate outside its range; years left that are not a whole number from 0 to 30, or an expected life that is not a whole number from 1 to 40. NOT VALID is a refusal, not a numeric answer: every figure reads zero and is withheld.
• CHECK accompanies a computed result that needs the stated review: an old unit described by the year it was made, so its figure is the federal limit for that year: your unit may use less and the saving may be overstated; a manual entry whose rating basis is Unknown; one unit rated by EF and the other by IEF, so the old unit's energy and the saving are probably understated; old and new units of different types (portable and whole-home); a new unit that would need more than 8,760 hours a year to remove the same water; zero hours a year; a new unit that does not cost less to run than the old one at your use, so there is no payback; or an old unit with fewer years left than the years compared, so the end-of-life path is the realistic one.
• OK otherwise.

Assumptions and limitations

• The new unit removes the same water as the old one. The moisture load is set by the old unit's capacity and your hours; a bigger new unit runs fewer hours, not more water.
• 1,095 hours is the test basis, not your use. DOE's Appendix X1 counts 1,095 dehumidification-mode hours a year; your use enters only through the hours you set.
• The historical lists are snapshots. They hold the models listed when each ENERGY STAR specification changed; models in between are missing, the oldest list (Version 2) is not used, and older lists do not say whether a unit is portable or whole-home, so those units are treated as portable.
• The federal minimum efficiency is a floor, not a measurement. A unit described by the year it was made may use less energy, so the saving may be overstated.
• Expected life. No federal lifetime for dehumidifiers was found; enter the new unit's expected life if you want the value left in it at the end to count.
• The default electricity price is an average. It is the EIA's annual average residential price for the state, not your tariff. Enter your own price from your bill for a better answer.
• One price change rate applies to electricity in every year. The future purchase in the end-of-life path is priced at today's price.
• There is no loan, no depreciation other than the value left in the new unit at the end, and no resale other than the old unit's sale value when it is replaced now.

Data and vintage

The model lists and the federal standards are reviewed reference tables inside the workbook, refreshed from their federal publishers; their version is shown in the result details.

• Current models: the ENERGY STAR certified dehumidifiers dataset (EPA), Version 6.0, 571 records downloaded 2026-10-28 (portable 547, whole-home 24). Where a model is listed more than once, the most recent listing is used.
• Historical models: the ENERGY STAR Version 5 list (713 records, IEF), the Version 4 list (649, EF; 210 with no efficiency are left out) and the Version 3 list (396, EF), downloaded 2026-10-28.
• Year made: the federal minimum efficiency by capacity band from 10 CFR 430.32(v), from 2007-10-01, 2012-10-01 and 2019-06-13.
• Default electricity prices: EIA 2025 annual average residential electricity prices by state (Form EIA-861).

Worked examples and prices

Prices are not part of the reference data: the price of the new unit is an input you set. The opening example and the five worked examples each use an illustrative price for the new unit, so that the example computes, and each says so: “Illustrative price for this example, not a quote or a current price. Prices vary: check current prices online or enter your own.”

Restrictions and non-computing states

The calculator enforces its numeric and choice limits before it accepts a result. A model that is not in its list or does not match the type chosen, a unit made before the first federal standard described by its year, a manual unit with no capacity or efficiency and a missing price for the new unit are refused by the workbook.

Errors and warnings

A request rejected by the page's input limits is not a computed result. A transport or service failure, a timeout or a cancelled run cannot establish a fresh workbook answer, and the last result stays on the page marked as out of date. Check your unit's EnergyGuide label or nameplate and your own bills before relying on a result for a purchase.

Sources and further reading

The calculator reads its model lists, its federal limits and its default electricity prices from reviewed reference tables inside the workbook, by record, with their version shown in the result details. Every table comes from a US federal source. The sources below publish the data and the rules the model applies. They do not endorse this calculator.

• ENERGY STAR Certified Dehumidifiers (EPA) lists currently certified dehumidifiers with their capacity and integrated energy factor under DOE Appendix X1 (retrieved 2026-10-28).
• ENERGY STAR, Dehumidifiers: information for partners (EPA) links the historical lists of dehumidifiers certified under earlier specifications, Versions 2 to 5 (retrieved 2026-10-28).
• DOE test procedures, 10 CFR 430 Subpart B (eCFR), whose Appendix X1 defines the integrated energy factor and counts 1,095 dehumidification-mode hours a year (retrieved 2026-10-28).
• DOE energy conservation standards, 10 CFR 430.32 (eCFR) sets the federal minimum efficiency for dehumidifiers by capacity band (430.32(v)); the 2012 edition on govinfo holds the earlier standards (retrieved 2026-10-28).
• EIA, Detailed state data (Form EIA-861) gives the average residential electricity price by state, used here for 2025 (retrieved 2026-10-28).

This is an educational estimate of running and purchase costs for the units and prices you enter, not a product recommendation or a quote. The ENERGY STAR lists show each model's rated use under the DOE test procedure, not your unit's measured use.