AlorAir Sentinel HD55

The gap, and what causes it

Crawl space and commercial dehumidifiers are conventionally rated at saturation because the trade that buys them - water damage restoration - works in exactly those conditions after a flood. A restoration contractor comparing two units at saturation is making a sensible comparison.

The problem arrives when the same unit is sold to a homeowner on a retail site alongside 50-pint portables rated under the DOE procedure. On that shelf, 113 next to 50 looks like more than twice the machine. On a common scale it is about three quarters of one.

And yet it is the right machine for a crawl space

This is the part a cynical reading would miss. Once the number is understood, the HD55 is genuinely well matched to its job, and for reasons that have nothing to do with capacity:

1. 1It fits. A flat, low body designed to sit under or between joists in a space you cannot stand up in. No standing portable does this, and a portable that will not fit is not a cheaper alternative, it is no alternative.
2. 2It works cold. Auto defrost and low-temperature operation as standard. A crawl space sits near ground temperature year round, which is exactly where an ordinary compressor unit ices and stops.
3. 3It has no tank. Which is the correct design decision: nobody empties a bucket in a crawl space, so the machine is built to drain or not to run.
4. 4It is efficient. IEF 2.08 against the 50-pint portable class median of 2.01, at 344 W and 379 kWh a year. It removes less water than a 50-pint portable and it does so more efficiently per liter.
5. 5Six-year limited warranty, per AlorAir's listing, against most portables' one year. For a machine nobody will look at for years at a time, that is a meaningful part of the value.

Quick picks

#	Product	Best for	Draw	Price
1	AlorAir Sentinel HD55 Crawl Space DehumidifierThe clearest example on this site of why the number on the box is not the number that matters: sold as 113 pints, certified at 36.33.	A crawl space you cannot stand up in	344 W	Check price on Amazon #ad How we are funded
2	AlorAir Sentinel HDi65S Crawl Space Dehumidifier with PumpA low-clearance unit with the condensate pump built in, which is the only sane configuration for a space whose floor is the lowest point on the property.	A crawl space with nowhere for water to go	Not published	Check price on Amazon #ad How we are funded

1

AlorAir

AlorAir Sentinel HD55 Crawl Space Dehumidifier

Best for: A crawl space you cannot stand up in

The clearest example on this site of why the number on the box is not the number that matters: sold as 113 pints, certified at 36.33.

Average draw

344 W

Computed from the ENERGY STAR certified entry ALORAIR Sentinel HD55S: 36.33 pt/day at IEF 2.08 L/kWh, 379 kWh a year. The retail listing is the HD55; the certified entry carries the S suffix. At IEF 2.08 it is more efficient than the median 50-pint portable while removing about three quarters as much water.

What is good

• +Built low and flat to fit between floor joists, which no portable unit does
• +Auto defrost and low-temperature operation, both essential in an unheated crawl space
• +IEF 2.08 is above the 50-pint class median of 2.01 despite the smaller capacity
• +No tank at all, so there is nothing to forget to empty

What is not

• -The 113-pint headline is a saturation figure at 95F and 90% RH; the DOE-condition rating is 36.33
• -1,200 sq ft coverage, less than most 50-pint portables claim, for considerably more money
• -Needs a drain or a condensate pump - there is no bucket fallback

Who it is for

Crawl spaces, low-clearance basements and unheated storage where a standing portable will not fit or will freeze.

Skip it if

Skip it for a normal basement. A 50-pint portable removes more water at the DOE condition for less money; you are paying for the form factor and the temperature range.

2

AlorAir

AlorAir Sentinel HDi65S Crawl Space Dehumidifier with Pump

Best for: A crawl space with nowhere for water to go

A low-clearance unit with the condensate pump built in, which is the only sane configuration for a space whose floor is the lowest point on the property.

Average draw

Not published

Not published, and the HDi65S does not appear by name in the ENERGY STAR certified list - AlorAir's certified entries are the Sentinel HD55S (344 W), the Helios D35 (243 W) and the Sentinel Pro35X (221 W). Given the HD55S computes to 344 W at 36 DOE pints, a genuinely larger AlorAir unit sits above that. We are not going to put a figure on it without a source.

What is good

• +Condensate pump built in, so the discharge can go up and out rather than down and nowhere
• +Compact enough for low-clearance crawl spaces and joist bays
• +Auto defrost, MERV-1 filter, cETL listed
• +Optional remote monitoring, which matters for a machine nobody looks at

What is not

• -No published wattage and no named ENERGY STAR entry
• -The 120-pint headline is a saturation number, as with every unit in this class
• -Expensive relative to a portable of comparable DOE capacity

Who it is for

Encapsulated crawl spaces and sub-floor voids with no gravity drain, where the alternative is a bucket nobody will ever empty.

Skip it if

Skip it if you have a floor drain below the unit. The HD55 does the same job on gravity for less, and has a certified efficiency figure this one lacks.

The suffix, stated

The retail listing is the Sentinel HD55. The ENERGY STAR certified entry is the Sentinel HD55S. AlorAir's certified entries are the HD55S, the Helios D35 and the Sentinel Pro35X; the HDi65S sold alongside it does not appear at all, which is why that unit's page carries no computed wattage.

We use the HD55S figure for the HD55 and say so here, because a reader who checks the certified list should find the same thing we did rather than a discrepancy we did not mention.

Who should not buy it

Anyone with a normal basement. A 50-pint portable removes more water at the DOE condition, costs considerably less, and fits fine in a room with headroom. The HD55's price buys a form factor and a temperature range that a basement does not need.

And anyone whose crawl space is not sealed. A dehumidifier in a vented, bare-earth crawl space is dehumidifying the outdoors - ground moisture evaporates continuously and vent air brings its own. Vapor barrier first, machine second. Crawl space roundup.