Elecraft

Quiet Ductless HVAC System

Classic

List

Threaded

26 messages Options

Albert Reynolds

Quiet Ductless HVAC System

Does anyone have suggestions for an RF quiet ductless, also called a "mini
split" heat pump system. I am in need of a small (12000 BTU) system for the
ham shack. Comments from anyone who has used such a system, or successfully
mitigated RFI on a system would be appreciated. Brand and model number would
be highly appreciated.

Albert, N4AGG

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Art Greenberg

Re: Quiet Ductless HVAC System

Albert,

I have an 18,000 BTU mini-split cooling my wood shop and radio shack. I started with a high-end Lennox mini-split. When it died out of warranty I could not justify the extra cost to go with the same model over a Mitsubishi. No detectable RFI from either.

The Lennox was MS7-HO-18P outside and MS7-HI-18P inside.

I'll have to get back to you with model numbers for the Mitsubishi. I cannot locate that information at the moment.

--
Art Greenberg
WA2LLN
[hidden email]

On Wed, May 27, 2020, at 07:09, Albert Reynolds wrote:

> Does anyone have suggestions for an RF quiet ductless, also called a "mini
> split" heat pump system. I am in need of a small (12000 BTU) system for the
> ham shack. Comments from anyone who has used such a system, or successfully
> mitigated RFI on a system would be appreciated. Brand and model number would
> be highly appreciated.
>
>
>
> Albert, N4AGG
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

Richard Thorne-4

Re: Quiet Ductless HVAC System

In reply to this post by Albert Reynolds

I purchased 2 Ramson Units from https://www.ac-world.com/

One for my ham shack and one for my Wife's storage that holds all of her
Special Olympics equipment.

I installed it myself and then had an HVAC company come over to purge
the lines etc just to be sure it was done correctly.

Rich - N5ZC

On 5/27/2020 6:09 AM, Albert Reynolds wrote:

Ed Pflueger

Re: Quiet Ductless HVAC System

I have the Mitsubishi system and no issues..

Ed.. AB4IQ

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Richard Thorne
Sent: Wednesday, May 27, 2020 7:47 AM
To: Albert Reynolds <[hidden email]>; [hidden email]
Subject: Re: [Elecraft] Quiet Ductless HVAC System

I purchased 2 Ramson Units from https://www.ac-world.com/

One for my ham shack and one for my Wife's storage that holds all of her
Special Olympics equipment.

I installed it myself and then had an HVAC company come over to purge the
lines etc just to be sure it was done correctly.

Rich - N5ZC

On 5/27/2020 6:09 AM, Albert Reynolds wrote:

> Does anyone have suggestions for an RF quiet ductless, also called a
> "mini split" heat pump system. I am in need of a small (12000 BTU)
> system for the ham shack. Comments from anyone who has used such a
> system, or successfully mitigated RFI on a system would be
> appreciated. Brand and model number would be highly appreciated.
>
>
>
> Albert, N4AGG
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net Please help support this email
> list: http://www.qsl.net/donate.html Message delivered to
> [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html Message
delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

NK7Z

Re: Quiet Ductless HVAC System

In reply to this post by Albert Reynolds

Hi Albert,

Here are a few suggestions... When I added my furnace, I made it part
of the purchase contract that there was to be no new RFI. This makes
the vendor very careful. Tell them it is a showstopper, and they will
be responsible for RFI removal if RFI comes with the new purchase. Get
it in writing if possible.

Insist they call the manuafacturer and ask about RFI for the unit you
are considering, and are there RFI kits for that unit, PRIOR to your
purchase...

Be careful assuming brand and model numbers will remain RFI quiet over
time. Vendors change parts, and circuits, within a fixed model number
all the time... What is RFI quiet today, may not be RFI quiet tomorrow...

Take measurements first, before the install, and after install. Use
this process:

https://www.nk7z.net/sdr-rfi-survey-p1/

It is part I of III in a series on using an SDR to model your RFI
environment. Perform the tests, save the results, then run them all
again after install... I run a full sweep once a year here, and keep
the results... Also see my March 2020 article in CQ on this subject...

Good luck, and good for you for looking at this early!!!

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 5/27/20 4:09 AM, Albert Reynolds wrote:

Gary Johnson

Re: Quiet Ductless HVAC System

In reply to this post by Albert Reynolds

At our remote site, we have a new Mitsubishi 12000 BTU mini-split. It is located right under our 30 ft tower with Yagis and wire antennas. There is no detectable elevation of the noise floor nor any buzzing birdies on 160 thru 2m. An external thermostat adapter was installed, and on the cable to the thermostat I did apply a proper choke, just in case. All AC wiring is in Sealtite or EMT conduit.

Exact models are MSZ-GL12NA-U1 - indoor. MUZ-GL12NA-U2 - outdoor.

-Gary NA6O

>
> Does anyone have suggestions for an RF quiet ductless, also called a "mini
> split" heat pump system. I am in need of a small (12000 BTU) system for the
> ham shack. Comments from anyone who has used such a system, or successfully
> mitigated RFI on a system would be appreciated. Brand and model number would
> be highly appreciated.

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Gary-5

Re: Quiet Ductless HVAC System

In reply to this post by NK7Z

How did you find one that would agree to that? The 6 I've talked with all said pass as soon as I brought the subject up....

73,
Gary kk0sd

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Dave Cole
Sent: Wednesday, May 27, 2020 8:45 AM
To: [hidden email]
Subject: Re: [Elecraft] Quiet Ductless HVAC System

Hi Albert,

Here are a few suggestions... When I added my furnace, I made it part of the purchase contract that there was to be no new RFI. This makes the vendor very careful. Tell them it is a showstopper, and they will be responsible for RFI removal if RFI comes with the new purchase. Get it in writing if possible.

Insist they call the manuafacturer and ask about RFI for the unit you are considering, and are there RFI kits for that unit, PRIOR to your purchase...

Be careful assuming brand and model numbers will remain RFI quiet over time. Vendors change parts, and circuits, within a fixed model number all the time... What is RFI quiet today, may not be RFI quiet tomorrow...

Take measurements first, before the install, and after install. Use this process:

https://www.nk7z.net/sdr-rfi-survey-p1/

It is part I of III in a series on using an SDR to model your RFI environment. Perform the tests, save the results, then run them all again after install... I run a full sweep once a year here, and keep the results... Also see my March 2020 article in CQ on this subject...

Good luck, and good for you for looking at this early!!!

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 5/27/20 4:09 AM, Albert Reynolds wrote:

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email]
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Bob McGraw - K4TAX

Re: Quiet Ductless HVAC System

My take on this is "prepare to do some noise mitigation yourself."
Jim, K9YC, has several good papers dealing with noise reduction and
methods to accomplish same. In general, adding correct type ferrite
chokes to the AC mains and the control lines is, in general, good
starting point.

Most HVAC companies are typically not versed in RFI technology and I
wouldn't expect them to be.

73

Bob, K4TAX

On 5/27/2020 11:14 AM, Gary wrote:

> How did you find one that would agree to that? The 6 I've talked with all said pass as soon as I brought the subject up....
>
> 73,
> Gary kk0sd
>
> -----Original Message-----
> From: [hidden email] <[hidden email]> On Behalf Of Dave Cole
> Sent: Wednesday, May 27, 2020 8:45 AM
> To: [hidden email]
> Subject: Re: [Elecraft] Quiet Ductless HVAC System
>
> Hi Albert,
>
> Here are a few suggestions... When I added my furnace, I made it part of the purchase contract that there was to be no new RFI. This makes the vendor very careful. Tell them it is a showstopper, and they will be responsible for RFI removal if RFI comes with the new purchase. Get it in writing if possible.
>
> Insist they call the manuafacturer and ask about RFI for the unit you are considering, and are there RFI kits for that unit, PRIOR to your purchase...
>
> Be careful assuming brand and model numbers will remain RFI quiet over time. Vendors change parts, and circuits, within a fixed model number all the time... What is RFI quiet today, may not be RFI quiet tomorrow...
>
> Take measurements first, before the install, and after install. Use this process:
>
> https://www.nk7z.net/sdr-rfi-survey-p1/
>
> It is part I of III in a series on using an SDR to model your RFI environment. Perform the tests, save the results, then run them all again after install... I run a full sweep once a year here, and keep the results... Also see my March 2020 article in CQ on this subject...
>
> Good luck, and good for you for looking at this early!!!
>
> 73, and thanks,
> Dave (NK7Z)
> https://www.nk7z.net
> ARRL Volunteer Examiner
> ARRL Technical Specialist
> ARRL Asst. Director, NW Division, Technical Resources
>
> On 5/27/20 4:09 AM, Albert Reynolds wrote:
>> Does anyone have suggestions for an RF quiet ductless, also called a
>> "mini split" heat pump system. I am in need of a small (12000 BTU)
>> system for the ham shack. Comments from anyone who has used such a
>> system, or successfully mitigated RFI on a system would be
>> appreciated. Brand and model number would be highly appreciated.
>>
>>
>>
>> Albert, N4AGG
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net Please help support this email
>> list: http://www.qsl.net/donate.html Message delivered to
>> [hidden email]
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

NK7Z

Re: Quiet Ductless HVAC System

In reply to this post by Gary-5

Maybe they are more hungry out here in Oregon... They agreed and, (to
my great surprise), put it in the contract.

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 5/27/20 9:14 AM, Gary wrote:

NK7Z

Re: Quiet Ductless HVAC System

In reply to this post by Bob McGraw - K4TAX

I have two goals in talking RFI to the vendors, and manufacturers...

1. Make both the vendor, and manufacturer aware RFI issues may exist.
This might help the next poor sod down the road, in that the RFI issue
is no longer "new" to either vendor, or maker.

2. Gets RFI on the table in the event there is RFI, I can say, we
talked about this, and you said...

In my case, the vendor called the manufacturer prior to signing a
contract, and the manuafacturer said no issues at all, RFI wise. They
were right. The thing is dead quiet.

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 5/27/20 9:21 AM, Bob McGraw K4TAX wrote:

> My take on this is "prepare to do some noise mitigation yourself." Jim,
> K9YC, has several good papers dealing with noise reduction and methods
> to accomplish same. In general, adding correct type ferrite chokes to
> the AC mains and the control lines is, in general, good starting point.
>
> Most HVAC companies are typically not versed in RFI technology and I
> wouldn't expect them to be.
>
> 73
>
> Bob, K4TAX
>
>
> On 5/27/2020 11:14 AM, Gary wrote:
>> How did you find one that would agree to that? The 6 I've talked with
>> all said pass as soon as I brought the subject up....
>>
>> 73,
>> Gary kk0sd
>>
>> -----Original Message-----
>> From: [hidden email]
>> <[hidden email]> On Behalf Of Dave Cole
>> Sent: Wednesday, May 27, 2020 8:45 AM
>> To: [hidden email]
>> Subject: Re: [Elecraft] Quiet Ductless HVAC System
>>
>> Hi Albert,
>>
>> Here are a few suggestions... When I added my furnace, I made it part
>> of the purchase contract that there was to be no new RFI. This makes
>> the vendor very careful. Tell them it is a showstopper, and they will
>> be responsible for RFI removal if RFI comes with the new purchase.
>> Get it in writing if possible.
>>
>> Insist they call the manuafacturer and ask about RFI for the unit you
>> are considering, and are there RFI kits for that unit, PRIOR to your
>> purchase...
>>
>> Be careful assuming brand and model numbers will remain RFI quiet over
>> time. Vendors change parts, and circuits, within a fixed model number
>> all the time... What is RFI quiet today, may not be RFI quiet
>> tomorrow...
>>
>> Take measurements first, before the install, and after install. Use
>> this process:
>>
>> https://www.nk7z.net/sdr-rfi-survey-p1/
>>
>> It is part I of III in a series on using an SDR to model your RFI
>> environment. Perform the tests, save the results, then run them all
>> again after install... I run a full sweep once a year here, and keep
>> the results... Also see my March 2020 article in CQ on this subject...
>>
>> Good luck, and good for you for looking at this early!!!
>>
>> 73, and thanks,
>> Dave (NK7Z)
>> https://www.nk7z.net
>> ARRL Volunteer Examiner
>> ARRL Technical Specialist
>> ARRL Asst. Director, NW Division, Technical Resources
>>
>> On 5/27/20 4:09 AM, Albert Reynolds wrote:
>>> Does anyone have suggestions for an RF quiet ductless, also called a
>>> "mini split" heat pump system. I am in need of a small (12000 BTU)
>>> system for the ham shack. Comments from anyone who has used such a
>>> system, or successfully mitigated RFI on a system would be
>>> appreciated. Brand and model number would be highly appreciated.
>>>
>>>
>>> Albert, N4AGG
>>>
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
>>> This list hosted by: http://www.qsl.net Please help support this email
>>> list: http://www.qsl.net/donate.html Message delivered to
>>> [hidden email]
>>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

Elecraft mailing list

Re: Quiet Ductless HVAC System

In reply to this post by NK7Z

Same here when we replaced a package heat pump for the whole house. Made it part of the deal.
Contractor was fine with it - said more and more people are concerned with RFI due to abundant wi-fi networks and HDTV antennas being popular for cord cutters.
Hank
K4HYJ

----- Original Message -----
From: Dave Cole ([hidden email])
Date: 05/27/20 12:40
To: [hidden email]
Subject: Re: [Elecraft] Quiet Ductless HVAC System

Maybe they are more hungry out here in Oregon... They agreed and, (to
my great surprise), put it in the contract.

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 5/27/20 9:14 AM, Gary wrote:

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Elecraft mailing list

Re: Quiet Ductless HVAC System

In reply to this post by NK7Z

I didn’t know that an HVAC system would be an RFI generator. What part of HVAC is the cause of this and is this a recent problem in manufacturing units?

Note — I have never lived in a home with AC — never had a need here in the northwest (Seattle area). I probably should add that when we go to our condo on Kauai the first thing my wife does is to turn off the AC unit.

73, phil, K7PEH

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

NK7Z

Re: Quiet Ductless HVAC System

In reply to this post by Elecraft mailing list

Hi Hank,

Happy to hear this! As a group, ALL Amateur Operators, need to push
this issue with the install of any major appliance...

You may not get any satisfaction, but some will, it is a statistical
game... If enough manufactures here about RFI issues, they may start to
think it is harming sales, then they may well start dealing with this on
a proactive basis, as opposed to the reactive basis now in place.

I am pretty sure some Solar Companies are already doing this, as I got a
cold call from one a few years ago in the Oregon area wanting me to come
out to their assembly plant and look over a few of their systems they
had set up for RFI testing!

We IDed a number of RFI issues. I brought a boat load of ferrite
material with me, and was able to quiet down most of the RFI issues.

They took notes on the material I used, and what I did to quiet things
down. I assume they either add them proactively, or add them as
needed... Whatever, the outcome was positive RFI wise.

I also pointed them at Mike G, and Ed H., at the ARRL labs, and I assume
some discussions went on there as well.

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 5/27/20 9:53 AM, Hank wrote:

>
> Same here when we replaced a package heat pump for the whole house. Made it part of the deal.
> Contractor was fine with it - said more and more people are concerned with RFI due to abundant wi-fi networks and HDTV antennas being popular for cord cutters.
> Hank
> K4HYJ
>
> ----- Original Message -----
> From: Dave Cole ([hidden email])
> Date: 05/27/20 12:40
> To: [hidden email]
> Subject: Re: [Elecraft] Quiet Ductless HVAC System
>
> Maybe they are more hungry out here in Oregon... They agreed and, (to
> my great surprise), put it in the contract.
>
> 73, and thanks,
> Dave (NK7Z)
> https://www.nk7z.net
> ARRL Volunteer Examiner
> ARRL Technical Specialist
> ARRL Asst. Director, NW Division, Technical Resources
>
> On 5/27/20 9:14 AM, Gary wrote:
>> How did you find one that would agree to that? The 6 I've talked with all said pass as soon as I brought the subject up....
>>
>> 73,
>> Gary kk0sd
>>
>> -----Original Message-----
>> From: [hidden email] <[hidden email]> On Behalf Of Dave Cole
>> Sent: Wednesday, May 27, 2020 8:45 AM
>> To: [hidden email]
>> Subject: Re: [Elecraft] Quiet Ductless HVAC System
>>
>> Hi Albert,
>>
>> Here are a few suggestions... When I added my furnace, I made it part of the purchase contract that there was to be no new RFI. This makes the vendor very careful. Tell them it is a showstopper, and they will be responsible for RFI removal if RFI comes with the new purchase. Get it in writing if possible.
>>
>> Insist they call the manuafacturer and ask about RFI for the unit you are considering, and are there RFI kits for that unit, PRIOR to your purchase...
>>
>> Be careful assuming brand and model numbers will remain RFI quiet over time. Vendors change parts, and circuits, within a fixed model number all the time... What is RFI quiet today, may not be RFI quiet tomorrow...
>>
>> Take measurements first, before the install, and after install. Use this process:
>>
>> https://www.nk7z.net/sdr-rfi-survey-p1/
>>
>> It is part I of III in a series on using an SDR to model your RFI environment. Perform the tests, save the results, then run them all again after install... I run a full sweep once a year here, and keep the results... Also see my March 2020 article in CQ on this subject...
>>
>> Good luck, and good for you for looking at this early!!!
>>
>> 73, and thanks,
>> Dave (NK7Z)
>> https://www.nk7z.net
>> ARRL Volunteer Examiner
>> ARRL Technical Specialist
>> ARRL Asst. Director, NW Division, Technical Resources
>>
>> On 5/27/20 4:09 AM, Albert Reynolds wrote:
>>> Does anyone have suggestions for an RF quiet ductless, also called a
>>> "mini split" heat pump system. I am in need of a small (12000 BTU)
>>> system for the ham shack. Comments from anyone who has used such a
>>> system, or successfully mitigated RFI on a system would be
>>> appreciated. Brand and model number would be highly appreciated.
>>>
>>>
>>>
>>> Albert, N4AGG
>>>
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
>>> This list hosted by: http://www.qsl.net Please help support this email
>>> list: http://www.qsl.net/donate.html Message delivered to
>>> [hidden email]
>>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email]
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

NK7Z

Re: Quiet Ductless HVAC System

In reply to this post by Elecraft mailing list

Of late, the fans in these systems are speed controlled by PWM. Nice
high power square waves...

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 5/27/20 10:08 AM, Phil Hystad wrote:
> I didn’t know that an HVAC system would be an RFI generator. What part of HVAC is the cause of this and is this a recent problem in manufacturing units?
>
> Note — I have never lived in a home with AC — never had a need here in the northwest (Seattle area). I probably should add that when we go to our condo on Kauai the first thing my wife does is to turn off the AC unit.
>
> 73, phil, K7PEH
>
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Rick Bates, NK7I

Re: Quiet Ductless HVAC System

Just as other appliances sold these days with a motor i.e. washing
machines, dishwashers... while digital control may add nice features,
the noise generated can reduce operator pleasure (or operating hours).

Getting any manufacturer to routinely add filtering (even if under $1),
won't happen without a lot of customer noise in return. ;-)

Rick NK7I

On 5/27/2020 10:17 AM, Dave Cole wrote:

> Of late, the fans in these systems are speed controlled by PWM. Nice
> high power square waves...
>
> 73, and thanks,
> Dave (NK7Z)
> https://www.nk7z.net
> ARRL Volunteer Examiner
> ARRL Technical Specialist
> ARRL Asst. Director, NW Division, Technical Resources
>
> On 5/27/20 10:08 AM, Phil Hystad wrote:
>> I didn’t know that an HVAC system would be an RFI generator. What
>> part of HVAC is the cause of this and is this a recent problem in
>> manufacturing units?
>>
>> Note — I have never lived in a home with AC — never had a need here
>> in the northwest (Seattle area). I probably should add that when we
>> go to our condo on Kauai the first thing my wife does is to turn off
>> the AC unit.
>>
>> 73, phil, K7PEH
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

ANDY DURBIN

Quiet Ductless HVAC System

In reply to this post by Albert Reynolds

"Just as other appliances sold these days with a motor i.e. washing machines, dishwashers... while digital control may add nice features, the noise generated can reduce operator pleasure (or operating hours)."

It's not a new problem. My over 30 year old Maytag washing machine with crude mechanical sequencer is a horrible RFI generator. Huge noise bursts with every motor run period.

I'm glad my 35 year old heat pump is still running. It's single speed, all mechanical timing and control, and RF silent. I have no problem turning off the washing machine to operate but turning off the AC is not really an option in Arizona.

Andy, k3wyc
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Phil Kane-2

Re: Quiet Ductless HVAC System

In reply to this post by Rick Bates, NK7I

On 5/27/2020 10:23 AM, Rick Bates, NK7I wrote:

> Getting any manufacturer to routinely add filtering (even if under $1),
> won't happen without a lot of customer noise in return. ;-)

Of course the pressure should be at the design stage, not the retrofit
stage, but good luck getting that to happen. The first thing is to get
the manufacturer - or the industry as a whole - to admit that there's a
problem. Good luck on that one, too. We've fought that on the
susceptibility-to-unwanted-pickup aspect for decades with very spotty
results.

73 de K2ASP - Phil Kane
Elecraft K2/100 s/n 5402

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Jim Brown-10

Re: Quiet Ductless HVAC System

In reply to this post by Bob McGraw - K4TAX

On 5/27/2020 9:21 AM, Bob McGraw K4TAX wrote:
> My take on this is "prepare to do some noise mitigation yourself." Jim,
> K9YC, has several good papers dealing with noise reduction and methods
> to accomplish same. In general, adding correct type ferrite chokes to
> the AC mains and the control lines is, in general, good starting point.

My advice on this is to ALWAYS confront the issue BEFORE buying the
unit/system in question. NK7Z's post at 8:45 am on May 27 outlines how
we should approach the issue. Put the onus on the vendor/installer, rule
out those who give a blank stare or don't want to learn or to do
anything about it.

And get it in writing -- if it isn't quiet, remove it and provide full
refund. And if it was replacing an existing system, restore that system,
also at no cost. When we insist on these provisions, the good vendors
will figure out what they need to make it work, the losers will vanish.

73, Jim K9YC
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Lynn W. Taylor, WB6UUT-3

Re: Quiet Ductless HVAC System

In reply to this post by NK7Z

The compressor as well. They aren't necessarily running at 60 Hz (or 50
Hz for those across the pond).

73 -- Lynn

On 5/27/20 10:17 AM, Dave Cole wrote:

Clay Autery-2

Re: Quiet Ductless HVAC System

In reply to this post by Elecraft mailing list

As I understand it.... ANY part of the HVAC system that uses a motor or
reciprocating drive mechanism that runs off AC current. Anything that
runs off DC current that is sourced from AC current via a switch mode
power supply, any part of the system that has an ECM, et al. electronic
"futzing" device that might produce an oscillating signal.

MOSTLY the air handling unit usually, and specifically the variable
frequency drives, electronic control modules, et al.... whatever they
are called.... NOT properly filtered, wired, suppressed, then they can
be a source of RFI.

______________________
Clay Autery, KY5G
(318) 518-1389

On 05/27/20 12:08, Phil Hystad via Elecraft wrote:

> I didn’t know that an HVAC system would be an RFI generator. What part of HVAC is the cause of this and is this a recent problem in manufacturing units?
>
> Note — I have never lived in a home with AC — never had a need here in the northwest (Seattle area). I probably should add that when we go to our condo on Kauai the first thing my wife does is to turn off the AC unit.
>
> 73, phil, K7PEH
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]