The Della Vario Series 12000 BTU is a ductless mini split meant for one larger room: think main bedroom, garage conversion or compact open-plan living space. It is the second of Della’s four mini split lines, sitting above the entry tier and below the cold-climate line.
Nothing here comes from hands-on testing. This is a close read of the specs, warranty terms and policies Della publishes, so numbers are credited to the brand wherever they come from it.
The short version: it suits a room up to about 550 square feet, provided your winter nights stay above -4°F and you plan on a licensed installer.
What the Vario 12000 BTU Offers
Della rates this size for rooms up to roughly 550 square feet. Here is the spec picture in one place.
- Coverage: up to about 550 square feet.
- Efficiency: 21 SEER2 on the main model, with a 23 SEER2 version also sold.
- Heating range: Della rates it to keep producing heat down to -4°F outside.
- Indoor sound: Della lists around 28 dBA on the low fan setting.
- Smart controls: WiFi through the Della+ app, plus Alexa and Google Assistant support.
- Price: about $850 at Della for the 21 SEER2 model.
Sizing matters as much as the model. Pick a unit with too little capacity and it labors around the clock, which can push electric bills up and wear the equipment out sooner. When your room sits between two sizes, round up. Della’s 9,000 BTU size is the one aimed at rooms nearer 350 to 400 square feet.
A reading of 28 dBA is close to the sound of rustling leaves, which is why the unit suits a bedroom at night. A quiet library is usually described as sitting around 30 to 40 dBA, so Della’s figure lands just under that.
The app handles scheduling and remote control, and the voice assistants let you adjust the room without hunting for the remote. To see what Della currently offers, browse the lineup on Della’s own site.
What Stands Out
A few things set this unit apart, based on what Della publishes.
- Price range. At this capacity, Della units generally fall between about $650 and $900, with the exact figure tied to the series and efficiency rating.
- Warranty depth, with a condition. Parts coverage turns lifetime once the unit is registered inside the 100-day window after purchase.
- Quiet indoor head. Della lists around 28 dBA on low, a level that suits sleeping spaces.
- Design recognition. Della has earned a Red Dot design award.
- App control. WiFi scheduling and voice control come with the Della+ app.
Now the trade-offs. Installation is a separate cost, because this is not a DIY product. Della was founded in 2012, which is a real record but a shorter one than HVAC names like Mitsubishi or Carrier. And the warranty never covers labor, so a service visit still means paying a technician.
Where Vario Sits in Della’s Lineup
Della sells four mini split lines, and the names alone do not explain the gaps between them. Winter lows are the deciding factor.
- Motto: the entry tier for moderate climates, built for cooling and light supplemental heat.
- Vario: higher efficiency than Motto, with SEER2 ratings of 19, 21 or 23 depending on the model, and heating rated down to -4°F.
- Optima: the cold-climate line. Standard models are rated to -13°F and the top model, with Ultra Hyper Heat, to -22°F.
- Serena: the Energy Star-certified tier at 22 SEER2, with a lifetime warranty included from day one.
Vario fits homes where a cold night usually means roughly 10°F to 25°F outside. If your lows regularly fall below 0°F, Optima is the series built for that, and Vario is not.
Serena is worth a look if you value Energy Star certification and a lifetime warranty with no registration step. Its starting price of about $780 sits close to the Vario’s.
Style matters too. The Vario is a wall-mounted style, while the brand also sells ceiling cassettes, like the one below, that recess into the ceiling.
Installation and Upkeep
Installation is a job for a licensed HVAC technician, because Della’s mini splits use a standard vacuum-and-charge setup. The brand runs an installer locator to help you find one. Labor is its own line item, outside both the sticker price and the warranty.
Upkeep is light once the unit is running. Filter timing depends on the season: Della suggests every 2 to 4 weeks when the unit works hard and every 1 to 2 months in mild weather. Rinse the filter in warm water with a little mild detergent, and refit it only when it is completely dry.
Coils get their own cleaning at least once a year, indoor and outdoor, ideally before your busiest season. Beyond that, glance at the condensate drain now and then and keep the outdoor unit clear of leaves and debris. A yearly technician inspection completes the routine, and staying current on maintenance also supports a warranty claim if you ever need one.
Warranty, Returns and Shipping
Della’s mini split coverage works in three steps.
- Days 1 to 30: you can return the unit, or take free replacement parts.
- Day 31 through year one: free replacement parts, with free shipping on those parts.
- After year one: lifetime parts coverage, but only for units registered within 100 days of purchase.
Several things are never covered, whichever stage you are in: technician labor, flood or lightning damage, third-party components, and failures that trace back to poor installation or misuse. Whether coverage continues past year one comes down to registration, so put a reminder in your calendar for delivery day and file the receipt with your order confirmation.
The return window for mini splits is 30 days, and the unit must come back in working condition with all accessories and its original packaging. Once the window closes, the remedy is parts replacement, not a refund.
Delivery is free by ground, but only to the 48 continental states: PO boxes, Alaska, Hawaii, Puerto Rico and international addresses are not served. Orders process in about 1 business day (2 to 4 in peak season), followed by 1 to 3 business days in transit.
Vario vs MRCOOL
MRCOOL makes a natural comparison because of its pre-charged DIY lines. The two brands reach a similar buyer by different routes.
| Factor | Della Vario | MRCOOL DIY line |
| Installation | Licensed technician, vacuum and charge | Pre-charged lines, no vacuum pump needed |
| Heating rating | Down to -4°F | Around 5°F |
| Warranty | Parts only after day 30, lifetime parts if registered | 7-year compressor coverage as a baseline |
| Typical 12,000 BTU price | About $650 to $900 | Usually above $1,200 |
| App | Della+ | SmartHVAC |
Both brands include WiFi and voice-assistant support, so smart features are close to a tie. Once a technician’s fee is added to Della’s price, the totals often land near each other, sometimes with Della still ahead.
Pick MRCOOL if installing it yourself matters most. Pick the Vario if hiring an installer does not bother you and a lower unit price does appeal. To match the specs against your own room, see Della’s range at its site.
Common Questions
How big a room suits the 12,000 BTU Vario?
Della rates it for up to roughly 550 square feet, which suits a spacious bedroom, a garage conversion or a compact open-plan area.
Can I install it myself?
No. The vacuum-and-charge setup is licensed technician work, a step MRCOOL’s pre-charged DIY lines avoid.
How cold can it heat?
Della rates the Vario to -4°F. For regular lows below 0°F, Optima is the series rated for that.
Does it have an app?
Yes, it is called Della+. The app handles scheduling and remote control over WiFi, and the unit also pairs with Alexa and Google Assistant.
What does registering the unit change?
Registering within 100 days turns parts coverage after year one into lifetime coverage. It goes through Della’s registration page, and you will want your proof of purchase handy.
The Verdict
The Vario Series 12000 BTU is a straightforward pick from Della’s lineup for a single larger room. The spec sheet offers 21 SEER2 efficiency, a -4°F heating rating, about 28 dBA indoors, app control and parts coverage that turns lifetime once you register.
Buy it if your room is up to about 550 square feet, your winters stay above -4°F, and you are happy to hire a licensed installer and register the unit the day it arrives.
Skip it if you want a DIY install, your lows regularly drop below 0°F, or you are heating a space much larger than 550 square feet. In the cold-climate case, look at Optima instead.
Della is younger than the long-established HVAC names, so careful installation and on-time registration matter more than usual. When you are ready, visit Della’s site to find the Vario and confirm the current price.
