Santa Fe Ultra70 Review: Small Ducted Unit, Big Coil Question

The Santa Fe Ultra70 is the whole-house dehumidifier for a small, tight house or a single floor where nothing bigger will fit. It's a 12 by 12 inch box, 28 inches long, that hangs in an attic or sits in a closet, ducts with 8 in collars, filters through MERV-13, and can pull in outdoor air for ventilation. Santa Fe rates it at 52.45 pints a day at 73°F and 60% humidity, the same condition ENERGY STAR uses for whole-home units.

For most buyers, though, we'd spend about the same money on an AprilAire E080, which ENERGY STAR certifies at 65 pints at that condition, or step up to the E100 at 85. The Ultra70 earns its place when its size, its fresh-air port or its filter is what you need. Expect it to be heard through the ductwork, and keep the warranty paperwork: early evaporator leaks run through its owner record.

One naming note. Santa Fe's data sheet says the Ultra70 was previously the Ultra-Aire 70H, and the current version is part 4044100. The Compact70 is a different, crawl space unit, and the Ultra98, Ultra120 and Ultra155 are bigger machines with their own records.

Where it fits

• Tight spaces: a 12 in square cross-section and a rotating outlet panel that sends air out horizontally or straight up.
• Ventilation: an optional outdoor-air duct turns it into a ventilating dehumidifier, useful in an airtight house.
• Filtration: a MERV-13 filter in the cabinet, finer than the washable MERV 8 in AprilAire's units.
• Low power draw: 492 W and 4.1 A at the 73°F rating point, on an ordinary 15 A, 115 V circuit.

Where it doesn't

• Capacity: 52.45 pints at 73°F is modest for a whole house; AprilAire's E080 and E100 certify 24% and 62% more at the same condition.
• Efficiency: an integrated energy factor of 2.04 L/kWh against 2.35 for the AprilAire units, so it spends about 15% more electricity per pint.
• Noise in the ducts: owners hear it through the ductwork, and one finds it louder than their air conditioner.
• Coil failures: evaporator leaks and dead units in the first year or two come up in the owner record.

The ratings, and how they compare

Santa Fe publishes two numbers: 70 pints a day at 80°F and 60% humidity, the old industry rating, and 52.45 at 73°F and 60%, the DOE's whole-home condition. Size by the 52.45. At 73°F the unit removes 75% of what it does at 80°F, and less again in a 60°F basement. The Ultra70 isn't on ENERGY STAR's dehumidifier list, so the 73°F figure is Santa Fe's own.

On energy, 52.45 pints is about 24.8 liters. At 2.04 L/kWh that's roughly 12.2 kWh to remove a full day of rated capacity, close to what 492 W draws over 24 hours. The unit cycles off at its setpoint, so most days use less. The Compact70's 43.7 is measured at 65°F under the portable test, so it isn't directly comparable with the Ultra70's 73°F figure.

How much house it covers

Santa Fe says up to 1,800 sq ft, and its data sheet bases that on 10 ft ceilings (18,000 cubic feet). Treat it as a ceiling, not a target: one owner needed two of them, one on each floor of a two-story house, to bring humidity from 65% to the high 40s. A leaky house in a humid climate will keep a single unit running. If you're drying a whole house in the Gulf South or Southeast, size up to an E100 or a larger Santa Fe.

Where to put it and how to duct it

Santa Fe's manual says a qualified service technician should install it, and that matches how most of them go in: tied into an attic or closet air handler. Here's what the manual asks for, so you can judge a quote or plan the space:

• Recommended ducting: a dedicated 8 in return from a central spot in the house, never a bathroom or kitchen, with the dehumidifier's supply feeding the HVAC supply through a backdraft damper.
• Duct size and static: 8 in duct for up to 25 ft of total run, 10 in beyond that, and never more than 0.5 in. of static pressure. Airflow falls from 150 CFM to 130 at 0.4 in.
• Drain: a P-trap is required because the drain pan runs under negative pressure; without it water can back up and leak. Use 3/4 in pipe sloped 1 in per 10 ft, or a condensate pump.
• Over finished space: a secondary drain pan with a float switch under the unit.
• Power: a 9 ft cord to a 115 V outlet on a 15 A circuit; the manual calls for a dedicated GFCI-protected outlet near any water source.
• Control: the onboard humidistat sits in the unit; for an attic or crawl space install, a remote DEH300 or DEH300R control in the living space reads the house, not the attic.

The supply connection matters more than it looks. Feed dry air into the return side while the air conditioner's fan runs after a cooling cycle and the air picks the water back up off the wet coil, so humidity jumps. Ducting into the supply, with a backdraft damper, avoids that. The manual's preferred setup does exactly this.

If you use the outdoor-air port, plan for exhaust. A ventilating dehumidifier only pushes air in, and in a very tight house the incoming air needs somewhere to go; one owner with two units brought indoor CO2 under control only after setting exhaust fans to run on a schedule.

Without a nearby drain, a small pump such as the Little Giant VCMA-15 does the lifting, with the trap still in place between the unit and the pump.

Noise and reliability

Expect to hear it. The cabinet is rated 55.3 dBA on average, but owners say most of the sound arrives through the ductwork, with air rushing at the return grille; one crawl space owner adds that the fan cycles on every half hour to sample humidity even when the unit isn't drying. In an insulated attic or crawl space it fades into the background; next to a bedroom with a stud wall between, you'll notice it. Flexible duct at the collars, which the manual recommends, keeps vibration out of rigid ductwork.

Reliability is the bigger question. The most specific Ultra70 reports are about refrigerant leaks in the evaporator: two units that lost their charge within a year, and a new-construction unit that failed at 11 months. Owners of Santa Fe's larger Ultra models describe the same coil failures. Santa Fe's warranty has handled these with replacement units, by owners' accounts without much argument, but labor isn't included, and once an installer's own labor coverage runs out, swapping an attic unit is a paid service call. One owner of a ducted Santa Fe whole-house unit, model not named, also found mold on the coil side of the filter in a sealed crawl space, possibly because the filter sits close enough to the cold fins to drop below the dew point.

Most of these reports predate the current R454B unit, part 4044100, and there isn't enough owner history on it yet to say whether the coil record has changed.

The warranty

Santa Fe markets 6 years. The manual's written terms are 5 years on the product and 6 on its components, from the date of purchase, with Santa Fe choosing whether to replace a part or the whole unit. Labor, shipping, removal, reinstallation and installer-supplied materials aren't covered, and neither are used units bought from third parties. The warranty is void if a defect results from not following the installation instructions, and running without the recommended filter voids it outright. Register the unit at santa-fe-products.com, keep the receipt, and keep the recommended filter in it.

How it compares

• AprilAire E080: the one we'd cross-shop first. ENERGY STAR certifies it at 65 pints at 73°F, 24% more than the Ultra70, with a better efficiency figure and similar pricing when we checked. It has no ventilation port and a coarser filter.
• AprilAire E100: our pick for ducting into a whole house: 85 pints at 73°F, 280 CFM and 10 in ducts, at a higher price and in a bigger cabinet.
• Santa Fe Compact70: the crawl space version, rated 43.7 pints under the 65°F portable test, with the same MERV-13 filter and 49°F floor. Buy it for a sealed crawl space; buy the Ultra70 when you're ducting into living space.

Should you buy the Ultra70?

Buy it for a small or very tight house, a single floor, or an attic with no room for a bigger cabinet, especially if you want the fresh-air port or the MERV-13 filter. Duct it into the supply with a backdraft damper, give it a trapped drain, put the control in the living space, and register it the day it's installed.

If you're drying a whole house, or you have room for a bigger cabinet, the AprilAire E080 or E100 removes more water for the money. And if the noise matters, keep the return grille away from bedrooms.