Performance Test Results

Energy Efficiency

The measured power draw for this model at 50% relative humidity is 591 watts.

This makes it one of the more power hungry 50 pint dehumidifiers we tested – the average power draw for this size dehumidifier is 567 watts.

The KSTAD504F also took longer than average to lower humidity in our moisture removal test.

The bottom line – high power draw combined with a low moisture removal rate makes this model fairly energy inefficient according to our testing.

Noise Output

The KSTAD504F was measured at only 60.2 dB of noise output on high fan speed and 58.6 dB on low fan speed at a location right above and to the front of the unit’s control panel.

These are some of the lowest readings recorded among all of the high capacity (50 pint) dehumidifiers we’ve tested so far (and we’ve tested over 30 such units).

The KSTAD504F also does a fairly good job masking unpleasant compressor noise with more pleasant-sounding fan noise.

Overall, it does very well in this category.

Moisture Removal

The KSTAD504F took 10 minutes, 39 seconds to lower humidity in our 50 sq. ft. test room from 90% RH (relative humidity) down to 40% RH. This puts it in 11th place among the 16 large capacity dehumidifiers we’ve tested most recently.

The top rated Midea Cube took only 7 minutes, 39 seconds in the same test. So you can see how there’s a large gap between the Keystone and the Midea in real world performance, despite the fact that they’re both sold and marketed as “50 pint dehumidifiers”.

Hygrometer Accuracy

The KSTAD504D (previous Keystone we tested) had a highly inaccurate built-in hygrometer. This issue seems to be fixed with the KSTAD504F. The newer F model’s built-in hygrometer consistently gave readings within 3% of the actual room humidity while the older D model was only accurate to within 6% of the actual room humidity.

Included Features, Functionality, Build Quality, Warranties, and Value

Durability (Build Quality)

General Impressions

This is not a strong point for the KSTAD504F. The dehumidifier actually creaks when you pick it up from its side pocket handles. This behavior was unique to this model (compared to most other 50 pint dehumidifiers we tested).

It has a very low quality LED display, and its air filter is glued to the grille on the back of the dehumidifier.

These are only a few examples of this unit’s below average build quality.

Consumer Feedback

Consumer reviews for this model are mostly positive. There are not an inordinate number of negative reviews remarking on the model’s lack of long term reliability like there are for many competitor models.

Overall Category Score

Overall, we still give this model only a 3/5 for durability, mostly based on our own experience handling and using it during testing.

Adjustability

This model features two fan speeds, a continuous mode, and an automatic mode.

Overall Category Score

Overall, we give the KSTAD504F a 4/5 for adjustability.

Versatility

Set Humidity Range

You can set a target humidity level between 35% and 85% on this dehumidifier. This is the standard range for this size (50 pint) and type (compressor based) of dehumidifier.

Operating Temperature Range

The operating temperature range for this model is 41° to 90° F – again, a fairly standard range for this type of dehumidifier.

Gravity Drainage

Here we see another improvement over the KSTAD504D. The older D model required an adapter and screws for gravity drainage. The new F model does not.

There is a port on the back of the KSTAD504F to which you can connect a garden hose without using any adapters or screws.

Built-in Pump

This model does not feature a built-in pump.

Overall Category Score

Overall, the KSTAD504F gets a 4.5/5 for versatility.

Extra Features

Temperature Reading

This model does not display room temperature. Most competitors also do not have this functionality.

Defrost

This model does feature an automatic defrost mode –it will automatically cycle off its compressor and only run its fan to de-ice its evaporator coil at lower temperatures. There’s also an LED on the control panel that lights up to alert you when this mode is activated.

Check Filter

This model also has an LED that lights up to alert you when you need to clean its air filter.

Overall Category Score

Overall, the KSTAD504F scores a 4/5 in the category.

Ease of Use

LED Display Clarity

There’s a plastic material over the LED display that gives it a “fuzzy” appearance. This makes it more difficult to read at an angle.

Setup Difficulty

Some of the buttons on the control panel are not clearly labeled and will absolutely require you to consult a manual to figure out what they do.

Filter Removal Difficulty

We didn’t have any difficulty pulling the grille and integrated air filter out of the back of the dehumidifier.

Manual Clarity

We didn’t have any trouble understanding or following this model’s user manual.

Water Tank Size

This model’s water tank has a capacity of 14.4 pints which is below average (15.7 pints).

Overall Category Score

Overall, the KSTAD504F scores only a 3.5/5 in the category, mostly because of its poorly labeled control panel and its small water tank.

Portability

This model is slightly lighter than average. It has a specified weight of 41.2 lb. vs the average for this size class of 42.5 lb.

It does have side pocket handles if you need to pick it up, and it has casters on the bottom to push it around on flat surfaces.

It has a strap on the back to hold its power cord and the manufacturer also includes a plastic bracket that you can install on the back of the dehumidifier around which you can more easily wrap the power cord.

Overall Category Score

Overall, this model scores a 4/5 for portability.

Warranty (Manufacturer’s)

This dehumidifier comes with a one year manufacturer’s warranty which is the industry standard for this size and type of dehumidifier.

Value

The KSTAD504F is frequently priced at $200 or even sometimes less than $200 which makes it one of the least expensive 50 pint dehumidifiers on the market.

As we’ve shown in this review, it doesn’t offer the best performance in our tests, but if you’re on a super tight budget and you absolutely need a 50 pint dehumidifier, it’s a decent option at these prices.