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hvac · 15W typical

Running a ventless gas heater (electric ignition) costs about $0.12/month.

That's the typical ventless gas heater (electric ignition) at 15W, run 4 hours a day at the US-average rate of 16.5¢/kWh. Change any of those and the number moves — use the calculator below to see yours.

Estimated cost

$0.12/month
$0.00 per day$1.45 per year720 Wh monthly
W

A ventless gas heater (electric ignition) draws full power only while the thermostat/compressor is running — about 1.6 effective hours at 15W across your 4-hour window.

How you use it

Cost shifts with how long it's on.

The same ventless gas heater (electric ignition) can cost very different amounts depending on usage patterns. Three common scenarios, at the US-average rate.

supplemental living room

$0.12

per month

evening heat in a rural or off-grid home

4 hrs/day·$1.45/yr

backup during outage

$0.36

per month

primary heat when power is out (needs generator for ignition)

12 hrs/day·$4.34/yr

cabin weekend

$0.24

per month

heating a cabin while visiting

8 hrs/day·$2.89/yr

Where you live

$0.22 spread between the cheapest and priciest states.

Same appliance, same hours of use, different zip code — the monthly cost varies this much.

StateRateMonthlyYearly
Hawaii41.2¢$0.30$3.61
California31.4¢$0.23$2.75
Massachusetts30.8¢$0.22$2.70
Connecticut28.7¢$0.21$2.51
Rhode Island27.9¢$0.20$2.44
New Hampshire24.6¢$0.18$2.15
Alaska24.3¢$0.17$2.13
New York22.3¢$0.16$1.95
Maine22.1¢$0.16$1.94
Vermont21.5¢$0.15$1.88
Michigan19.3¢$0.14$1.69
New Jersey19.1¢$0.14$1.67
Maryland18.4¢$0.13$1.61
Pennsylvania18.1¢$0.13$1.59
District of Columbia17.8¢$0.13$1.56
Wisconsin17.4¢$0.13$1.52
Delaware17.2¢$0.12$1.51
Illinois16.9¢$0.12$1.48
Ohio16.6¢$0.12$1.45
Nevada16.3¢$0.12$1.43
Indiana15.8¢$0.11$1.38
Virginia15.7¢$0.11$1.38
Minnesota15.6¢$0.11$1.37
Colorado15.4¢$0.11$1.35
Alabama15.2¢$0.11$1.33
West Virginia15.2¢$0.11$1.33
Florida15.1¢$0.11$1.32
New Mexico14.8¢$0.11$1.30
Texas14.8¢$0.11$1.30
Arizona14.7¢$0.11$1.29
South Carolina14.7¢$0.11$1.29
Kansas14.6¢$0.11$1.28
Georgia14.2¢$0.10$1.24
Iowa14.1¢$0.10$1.24
North Carolina13.9¢$0.10$1.22
Missouri13.6¢$0.10$1.19
Oregon13.4¢$0.10$1.17
Tennessee13.3¢$0.10$1.17
Kentucky13.2¢$0.10$1.16
Mississippi13.1¢$0.09$1.15
Oklahoma13.1¢$0.09$1.15
South Dakota12.7¢$0.09$1.11
Montana12.4¢$0.09$1.09
Nebraska12.2¢$0.09$1.07
Arkansas12.1¢$0.09$1.06
Washington12.1¢$0.09$1.06
Louisiana11.9¢$0.09$1.04
Wyoming11.6¢$0.08$1.02
North Dakota11.5¢$0.08$1.01
Utah11.4¢$0.08$1.00
Idaho11.3¢$0.08$0.99

Efficient vs. inefficient

A $3.37/year difference across the wattage range.

Swapping a high-draw model for an efficient one pays for itself. Here's what that looks like annually at typical usage.

Most efficient

5W

$0.04 per month

$0.48 per year

Typical

15W

$0.12 per month

$1.45 per year

High draw

40W

$0.32 per month

$3.85 per year

When it hits hardest

winter peak

Nov-Mar; common in rural homes without ducted HVAC.

Ways to cut the cost

  • 1

    Use a built-in thermostat rather than running continuously

    Cuts gas use 20-30%

  • 2

    Crack a window slightly — ventless units require oxygen replacement

    Prevents low-oxygen shutoff cycles (which waste ignition energy)

  • 3

    Use only as supplemental heat — check local code before installing

    Ventless heaters are banned in several states

Real-world wattages

Pulled from actual spec sheets.

BrandModelWatts
ProComML060HBA15W
Mr. HeaterMHVFB30LPT20W
EmpireVFSR-30-315W

Picks that actually move the needle

Three products worth comparing if you're thinking about upgrading or supplementing what you have.

Some links below are affiliate links. If you buy, we may earn a small commission — it never changes the price you pay, and we only recommend picks we would stand behind.

Mr. Heater Vent-Free Blue Flame Heater 30,000 BTU

Electric load is tiny — ignition and blower only

$230-290
Low-Oxygen Shutoff Safety Kit

Required safety gear for ventless gas use

$35-50
CO Detector (UL 2034)

Mandatory for any ventless gas appliance

$30-45

See also

Related appliances

Sources: www.energy.gov · www.energystar.gov

Last updated: 2026-04-13