High Velocity AC vs Low Velocity
I’ve been getting estimates to install AC in a boiler heated house. Options seem to be ductless, high velocity and low velocity AC. I’ve ruled out ductless due to aesthetics. One contractor was promoting low velocity over high velocity systems since the high velocity ones consume lots of electricity and burn-out fans, motors rapidly since…
I’ve been getting estimates to install AC in a boiler heated house. Options seem to be ductless, high velocity and low velocity AC. I’ve ruled out ductless due to aesthetics. One contractor was promoting low velocity over high velocity systems since the high velocity ones consume lots of electricity and burn-out fans, motors rapidly since the motors are not variable speed and run all the time. Is this an issue?
We had ductless put into our home last year. 4 units in a 3 BR, with the fourth unit in living room. Quiet, works brilliantly, and the heads are much less obtrusive than we thought they’d be. If your building is a landmarked masterpiece, maybe that won’t work for you, but I recommend it to EVERYONE. We went Mitsubishi Mr. Slim. Worked with Iceberg Mechanical, whom I heartily recommend.
If you are thinking about aesthetics, consider audible and tactile as much as visual. Split systems make less noise when running and can provide constant gentle airflow instead of cycling on and off with a thump and sudden gust of freezing air.
ductless rock. we have 3 of them in our 1 bedroom brownstone where the registers/intercoolers are all hidden away.
works perfectly. vendor is fujitsu.
I would not lend credence to a vendor who bad mouths the competition. Better to stress the benefits of what you are selling.
We have multiple high velocity and conventional AC installations.
We are entirely happy with our Unico brand high velocity systems. They are a little pricey compared to conventional.
On the concept level, high velocity attempts to pump air that has been cooled to a much lower temperature through physically smaller ducts.
To distribute this colder air, the ducts are constructed of more effectively insulated materials. the exterior dimensions can be much smaller than conventional, approximately 1/4 the size.
Once distributed, the colder air has to enter the room to be cooled. This is accomplished with flexible 2″ duct that we call spaghetti. These connect to small registers, about 5″ round. Depending on size, a room may require 2,3,4,5 registers.
If improperly installed, these may hiss, but usually they are quiet. If ou held your hand in front of a register, it would feel cold like a car AC.
If a space is designed from scratch for conventional HVAC, the large ducts can be camouflaged and hidden effectivelly.
In an existing historic home, the smaller sizes of the distribution ductwork is easier to hide. The spaghetti can be pulled thru a stud wall.
The outdoor condenser can be specced for high SEER, analagous to a conventional. We have done heat pump high velocity systems, that are neat in the shoulder seasons.
The Unico brand air handlers are stainless units that are of very high quality. To my knowledge I can’t remember ever replacing a fan motor.
All HVAC equipment comes in different qualities, across manufacturers but also within one manufacturer’s line. The cheapest, what we call euphemistically is “builder’s” quality. Lowest cost, who cares what happens 5 years from now.
High velocity suffers in price comparisons with conventional because it has no “value” line. When we rough-in a conventional AC job, we fabricate all the larger duct, and purchase the smaller ducts etc. Unico we are forced to use their proprietary materials.
Hope that helps clarify your options. Unico, pricey, but a step above.
It’s hard to respond because you received misleading information. The high velocity systems use ECM, i.e., variable speed, motors.
I’m not entirely happy with L&M. They oversold how little space the ductwork would occupy and how artfully they could place the vents and insulate blower sound. I found the owner hard to deal with. The system works and requires much less in the way of soffets than standard systems. You do hear the wind blowing when the system is on. Best to install this type of system if lots of walls are open.
No.I’ve had a few high velocity systems installed and have had no issues with any of them. They use the same condensers as traditional A/C systems. Low velocity will be cheaper unless the ductwork creates architectural problems. High velocity is supposed to be a bit more efficient because of better de-humidification but I have not perceived a difference. Also noise is not an issue if you have a good installer. L&M is good.