The ARRL has a 2017 presentation on their website titled "Resolving Furnace and A/C RFI Problems"
On Fri, Oct 4, 2019, 7:26 AM <[email protected]> wrote: > Hello Rob. . .I discussed this very topic with my furnace guy yesterday > doing annual service on my furnace. The furnace AC blower motors are > going > the way of the abacus. He said it won't be long before all furnace blower > motors will be DC. > > 73. . .Dave, W0FLS > > -----Original Message----- > From: Rob Atkinson > Sent: Friday, October 04, 2019 5:43 AM > To: [email protected] > Subject: Re: Topband: Furnace RFI > > Went through this about 2 years ago. Firstly, define "efficient." If > you mean over 90%, as in one of those two stage furnaces with PVC > handling moisture then you are consigned to having to use a variable > speed DC motor (there are no variable speed AC motors, only speed > settings you set manually at installation) that will cause RFI because > it is run on variable duration square wave DC. You will have to have > the HVAC contractor install a manufacturer supplied hush kit, or do it > yourself. The hush kits are over priced and many contractors are > unfamiliar with them and RFI. > > Or, you can do what I did and get a single stage 80% efficient furnace > that runs on an AC blower and accept 10% less efficiency and get on > with life. Mine is around 80K BTU, not extremely big. There are > larger ones, or were. I went with American Standard, an Ingersol Rand > brand name. There are around three companies that make all the > furnaces; IR is one of them. I've heard the AC blower furnaces are > going to be history in a few years after which they'll all be high > eff. DC because gov't is obsessed with this, but that's another topic. > > 73 > Rob > K5UJ > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
