What We Find Inside Bedford Systems
Almost nobody knows a mini-split needs cleaning. The filters get rinsed, the unit still blows cold, and the assumption is that it's fine. Meanwhile the blower wheel — the part you can't see without taking the cover off — is collecting everything the filter missed, staying damp through the cooling season, and growing mold on the vanes and the drain pan.
By the time someone calls us it's usually because of a smell when the system first kicks on, or because they finally looked up inside with a flashlight. Both are the same problem: two or three years of build-up on parts that were never designed to be cleaned from the outside.
Bedford homes present a different mix of mini-split systems than we typically see on Cape Cod. Many of the town's older Colonials, Capes and split-level homes were built with boilers and no ductwork, so mini-splits are often retrofitted into additions, finished basements, home offices and second-floor bedrooms. These installations commonly use multi-head systems, with several indoor units running off one outdoor condenser.
In Bedford's newer and renovated homes, high-efficiency cold-climate heat pumps are also being used as the primary source of heating and cooling, not simply as supplemental air conditioning. Because those systems run all year rather than three months, the indoor units accumulate dust, pet hair, pollen and microbial buildup considerably faster. Deep cleaning restores airflow, clears odors, and keeps each head working efficiently through Bedford's humid summers and long heating season.
A Recent Bedford Job
Richard — two-head Mitsubishi system
Two Mitsubishi Electric wall units — an MSZ-EF18NAW in the living room and an MSZ-EF15NAW in the master bedroom — running off a single MXZ outdoor condenser. Both blower wheels were black. There was visible mold across the vanes, the filter housing and down into the drain pan on both heads. Full teardown, wheels and coils cleaned, drain pans and condensate lines flushed, outdoor unit rinsed, system tested before we left.
Super job by Derek and his very able assistant! Everything about this experience was positive. The communication was clear and timely. The explanation and work was efficient, neat and effective. The result is a clean system! I got several quotes and by far Extreme was the best… bit worried that such a good quote would mean less effective work but was pleasantly surprised when the work was very professional and effective. Had no idea we had such dust and mold… did not know you need to have a deep clean every 2 years. But will now have Extreme Split Cleaning in our calendars for every 2 years.
What a Deep Clean Includes
Full teardown of each indoor head — blower wheel, evaporator coil, drain pan and condensate line cleaned properly, not wiped. Outdoor unit rinsed. Filters inspected and cleaned or replaced. System tested before we leave, and you get photographs of every unit before and after.
Most homes are a two to four hour job depending on how many heads you have. We work around you — no need to take the day off.
Questions We Get in Bedford
Why does my mini-split smell musty when it starts up?
That smell is almost always the blower wheel. It's the barrel-shaped fan behind the vanes, and it stays damp through the cooling season because that's where condensation forms. Dust sticks to it, the damp keeps it there, and mold grows on the wheel and down into the drain pan underneath.
You get the smell on start-up because the fan spins up and pushes air across all of it before the coil has cooled. It usually fades after a few minutes, which is why people learn to ignore it. Nothing you can spray in the vents reaches the wheel — it has to come apart.
What's the black stuff I can see inside my unit?
If you shine a light up past the vanes and see black or grey speckling, that is mold on the blower wheel and the housing around it. The photos further up this page are exactly that, from a Bedford home — the owner had no idea until we opened it up.
It isn't dirt that wipes off. It grows into the plastic and the foam around the drain pan, and every time the system runs it's blowing across that surface and into the room.
Can't I just clean the filters myself?
Worth doing, and it helps — but the filters are the part you can reach, and they're rarely the problem. On Richard's units above the filters were in reasonable shape. The blower wheels directly behind them were black. The filter catches the big stuff; what gets past it lands on the wet parts and stays there.
Do you take the unit off the wall?
No. The head stays mounted. We remove the cover and vanes, mask and bib the unit so nothing runs down your wall, and clean the coil, blower wheel and drain pan in place. Everything goes back exactly as it was, and we test the system before we leave.
How often does it actually need doing?
Every two years for most homes. Sooner if you have pets, run the system year-round for heat, or notice a smell when it starts up. Richard's units above were well past due and he had no idea — which is the normal case, not the unusual one.
How much does it cost?
It depends on how many indoor and outdoor units you have. The instant price calculator gives you a real number in about thirty seconds — no phone call, no waiting for a quote.
Book a Cleaning in Bedford
Bedford and the surrounding towns — Lexington, Concord, Burlington, Billerica, Carlisle.
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