Ventilation hood repair

Noise is not extraction

The most common thing we hear about a hood is that it is loud and the kitchen still smells. Those two facts belong together more often than not. A blower that is moving very little air is frequently louder than one moving a lot, because what you are hearing is turbulence and restriction rather than airflow.

The paper test settles it in five seconds. Run the hood on high and hold a sheet of paper up against the baffles. If it does not pin itself there, the system is not moving air, and the fault is somewhere between the baffle and the outdoors — not in the motor’s willingness to spin.

Where the restriction usually is

Baffles come first, and they are the owner’s job rather than ours. Baffle filters are designed to be pulled out and run through a dishwasher, and when they are neglected the grease bridges the gaps and the open area collapses. A hood with clogged baffles works hard and achieves nothing.

The duct run comes second, and it is where installation sins show up. Every elbow costs airflow. A long horizontal run costs airflow. Flexible duct where rigid should have been used costs a great deal of airflow. We cannot rebuild a duct run on a service call, but we can tell you honestly when the hood is healthy and the ductwork is the problem, which saves you paying for a blower you did not need.

The damper comes third. A backdraft damper is a set of light flaps that should swing open under airflow and fall closed when the hood stops. Grease gums them shut. Salt corrodes the pivots. A damper that only half opens strangles the whole system, and one that will not close lets outside air, humidity and insects come back down the duct.

The 400 CFM line, and why doors slam

If your hood is a serious one and your house is reasonably tight, there is a question worth asking: where is the air coming from?

A hood only exhausts what it can replace. Pull several hundred cubic feet a minute out of a sealed house and the house goes negative — interior doors suck shut, exterior doors get hard to open, and in the worst case a combustion appliance somewhere else in the building can be affected. The residential code recognises this and requires makeup air for kitchen exhaust systems rated over 400 CFM.

In practice, in this area, we see it most in the newer construction: Nocatee, Shearwater, SilverLeaf and the newer Jacksonville builds are built tighter than a 1950s Mandarin ranch house, and a big hood in a tight house without makeup air behaves badly. The older Riverside and Avondale kitchens have the opposite problem — they leak enough that makeup air was never an issue, but their duct runs were improvised decades ago.

Salt air eats the outdoor end first

Everything about a hood that lives outdoors is on borrowed time in the coastal ZIPs. Roof and wall caps corrode, damper pivots seize, and external blower housings in Ponte Vedra Beach, at the Beaches and in the older streets of St. Augustine age visibly faster than the same hardware ten miles inland. If a hood in a coastal kitchen has become loud, the odds are good that the noisy part is the one bolted to the outside of the house.

What we do

We check airflow, baffle condition, damper operation, blower balance and the control side, and we tell you which of those is your actual problem. We are an independent shop and we are not part of any manufacturer network. The visit is a $129 flat diagnostic, credited toward the repair, with a written estimate before anything is ordered. Genuine OEM parts, 90 days labor, 365 days parts.