Ductwork decides whether good equipment actually performs. Shemtov Systems designs, installs, tests and seals duct systems across Montgomery County, MD, including zoning and duct pressure testing. Call 240-355-3333.
Here at Shemtov Systems we understand that the correct sizing of HVAC systems and just as important the correct sizing and design of the air distribution systems is crucial in order to meet the heating and cooling load of the house accurately.
That is why we offer: Manual J heat load calculations, complete duct design, Zoning and air balancing, duct sealing, insulating, duct pressure testing and certifying the system. call us for FREE estimate.
Shemtov Systems – Expert Zoning Solutions for Your HVAC Needs Are you struggling to maintain a consistent temperature throughout your home? Uneven heating or cooling in different rooms can be frustrating and uncomfortable. This is where zoning comes into play.
Duct Pressure Testing Did you know that leaking supply ductwork causes expensive conditioned air to be wasted and dumped into your attic, crawlspace or garage instead of into your house? Leaks ducts in forced air systems are now recognized as
Complete Duct Systems Design and Installation Shemtov Systems offeres complete duct system installations to service an existing or new addition. Manual J and duct pressure testing are available. Shemtov Systems will design and install a complete duct system to service
Ductwork is the delivery system for everything a furnace, heat pump, or air conditioner produces, and it decides how much of that capacity reaches your rooms. Shemtov Systems designs, installs, seals, tests, and zones air distribution systems across Silver Spring, Montgomery County, and the Olney area. When rooms are uneven, or a newer system never performed the way its label promised, the ducts are the first place we look. Call 240-355-3333 to have yours evaluated.
Key takeaways
Equipment earns its rating in a laboratory at a specific airflow. In a humid climate like ours a cooling system is generally set up for 350 to 400 cubic feet per minute of air per ton; 400 is the common rule of thumb, and lower figures are used where the moisture load is high. When the ducts cannot deliver that, capacity falls and the number on the box stops describing your house. Getting air conditioner sizing right is only half the job.
Look for patterns, not single bad days. One floor that never catches up, registers that whistle, a return grille that roars, dust back within days of cleaning, or a new system that lowered the bill without fixing the discomfort: those point at distribution rather than equipment. Noise is the clearest tell, because it means air is moving faster than the duct was built to carry. Equipment faults announce themselves differently, as our guide to signs your furnace or AC needs repair describes.
Four different problems get four different answers. If the layout is missing, overloaded, or was never engineered, start with duct design and installation. If you suspect the system is losing air, or a permit requires proof, book duct pressure testing. If the ducts are sound but one floor or wing carries a very different load, HVAC zoning splits the system into separately controlled areas. If the worry is what the air carries rather than where it goes, look at whole-house air cleaners.
The median Montgomery County home dates to about 1978, and the communities closest to the District are older still; Takoma Park's median construction date is 1951. A house of that age is usually on its second or third generation of equipment while still running its first duct system. Finished basements and attic conversions then added conditioned rooms without adding trunk or return capacity, and runs were pushed into vented crawl spaces and attics because there was nowhere else to put them.
Measure first. Total external static pressure at the air handler, delivered airflow, and register temperatures show whether the existing system is being strangled. Correcting distribution first often changes the equipment decision, because a house with sealed, correctly sized ducts frequently needs less capacity than the old nameplate suggests. Buying a bigger system to overpower a duct problem means paying twice. Our overview of HVAC replacement cost in Maryland shows where the money goes.
Yes. Moisture removal depends on the coil getting its design airflow over long, steady run times, so restricted ducts hurt summer comfort even when the thermostat reads right.
No. Cleaning removes debris from inside the ducts. It does not change duct size, static pressure, leakage, or layout, and those are what leave one room warm and another cold.
Often. Attic, basement, and crawl space runs are reachable, so sealing, resizing takeoffs, adding a return path, and replacing failed boots rarely need finish work. Openings are needed mainly when a run has to change route.
No. Zoning redirects air the ducts can already carry; it cannot create airflow the trunk and returns were never sized for. Closing dampers on an undersized system raises pressure and noise. Sizing gets corrected first, then zoning is worth doing.
Have your duct system evaluated before you spend money on new equipment. Call Shemtov Systems at 240-355-3333 or use our contact page to ask for a free estimate on duct design, sealing, testing, or zoning in Silver Spring, Montgomery County, and the Olney area.
Straight answers to the questions we hear most from Montgomery County homeowners.
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