Ping Larkin
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From: Joerg on 29 Oct 2009 16:37 Jim Thompson wrote: > On Thu, 29 Oct 2009 11:28:50 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> Jim Thompson wrote: >>> On Thu, 29 Oct 2009 11:10:28 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: >>> >>>> krw wrote: >>>>> On Tue, 27 Oct 2009 11:16:29 -0700, Joerg <invalid(a)invalid.invalid> >>>>> wrote: >>>>> >>>>>> Charlie E. wrote: >>>>>>> On Mon, 26 Oct 2009 23:00:28 +0000, Martin Brown >>>>>>> <|||newspam|||@nezumi.demon.co.uk> wrote: >>>>>>> >>>>>>>> Joerg wrote: >>>>>>>>> ChrisQ wrote: >>>>>>>>>> Joerg wrote: >>>>>>>>>>> On the news a few days ago: They had to close the "environmentally >>>>>>>>>>> compliant" new wing of a school because of H1N1. The old (real) >>>>>>>>>>> buildings exhibited little problems because you could open windows, >>>>>>>>>>> "hallways" were outdoors, etc. The newfangled building was >>>>>>>>>>> essentially a giant petri dish and so the kids there got sick. So >>>>>>>>>>> much for progress. >>>>>>>> That is a weakness of a lot of the no external opening windows designs. >>>>>>>> Sick building syndrome as the formaldehyde and other junk from the >>>>>>>> furniture and carpets accumulates in a poorly ventilated space. There is >>>>>>>> no excuse for not having fresh air heated by outgoing stale air though. >>>>>>> <snip> >>>>>>> >>>>>>> My home here (three years new) has not only double pane windows, it >>>>>>> also has plastic sealing in all the exterior walls. In a 70 mph wind, >>>>>>> there are only a few places where I can feel a draft - one by a wall >>>>>>> outlet, and the other around my back door. The door flexes enough to >>>>>>> release the weather stripping! >>>>>>> >>>>>>> But, my HVAC system also has a timer that causes it to go on with the >>>>>>> fan only at least every so often, and the system has an intake to the >>>>>>> outside for fresh air. ... >>>>>> I've always wondered where to get those. It would need to be before the >>>>>> filter or have its own filter. This whole concept of whole house fans is >>>>>> so strange, they rely on venting out instead of in so all the dust and >>>>>> pollen is sucked into the house. In Australia there are (IIRC) systems >>>>>> that blow in instead, makes a lot more sense. Never seen that in the US. >>>>> I put one in my NY house. It worked. We didn't have AC so between >>>>> the whole house fan and pool we survived. ;-) The key to the whole >>>>> house fan was blowing the attic out in the evening and cooling the >>>>> house down. We then closed it up during the day. If you're going to >>>>> have windows open at all you'll have pollen in the house. I prefer >>>>> windows open, if possible. I certainly don't want the dust and >>>>> insulation from the attic in the house! >>>>> >>>> All you'd have to do there is lay a duct to the end of the attic, then >>>> put the fan and a filter there. But nobody makes them :-( >>> Never made your own ductwork? When I was a kid in Jr. High and High >>> School, sheet metal shop was a requirement for all males (before equal >>> rights... the girls had to take Home Economics ;-) >>> >> Sure I did. But you can't get the proper fans with filters up front. I >> mean a kind that would pass inspection. > > You're putting the filters in the wrong place. > > (1) EXHAUST blower in attic blowing out an external vent. > > (2) Electrically-controlled louver to connect to interior AC ductwork, > sucking house air out into attic, then to outside world. > > (3) Inlet to interior of house from outside, somewhere (me, I might > just cut a "window" in the side of the house ;-) outfitted with > filter(s). > >> >>>> I was thinking about a 6" or 8" inline fan and making my own filter. But >>>> I doubt that's going to be even close in terms of required airflow. >>> Since this would be at mild weather and/or attic exchange rate, I'd >>> guess a 1000-2000CFM squirrel cage would do it. I'd probably use 4 >>> 20"x30" A/C filters (in an array). >>> >> Pleated filters in an array for outside air intake would get expensive. >> At least around here. > > So use cheapy fiberglass. (Pleated might not pass enough air anyway.) > So, essentially then you made a whole house fan with a hole in the house :-) Problem with that, huge: Someone goes out the patio door, only closes screen or leaves it all open. Speaking in electrical terms the transconductance of that screen is much higher than that of your hole, meaning most of the filter gets bypassed, meaning yellowish greenish pollen everywhere. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Michael A. Terrell on 29 Oct 2009 16:48 Joerg wrote: > > Michael A. Terrell wrote: > > Joerg wrote: > >> Easy with a mechanical timer if needed. But that's what the CD4060 was > >> invented for. Maybe that's too difficult for a HVAC mfg ... > > > > > > Mechanical timers ignore power outages. > > > > You can make both do either/or. Mech times with li'l tic-toc movement in > there, got one of those here. A CD4060 can be run off a large cap for a > looong time. If designed right, and that's the trick. I prefer the mechanical design, because of the high number of lightning strikes around here. If you want to sign off on a CMOS design, go ahead. Its your reputation, not mine. -- The movie 'Deliverance' isn't a documentary!
From: Jim Thompson on 29 Oct 2009 16:50 On Thu, 29 Oct 2009 13:37:09 -0700, Joerg <invalid(a)invalid.invalid> wrote: >Jim Thompson wrote: >> On Thu, 29 Oct 2009 11:28:50 -0700, Joerg <invalid(a)invalid.invalid> >> wrote: >> >>> Jim Thompson wrote: >>>> On Thu, 29 Oct 2009 11:10:28 -0700, Joerg <invalid(a)invalid.invalid> >>>> wrote: >>>> >>>>> krw wrote: >>>>>> On Tue, 27 Oct 2009 11:16:29 -0700, Joerg <invalid(a)invalid.invalid> >>>>>> wrote: >>>>>> >>>>>>> Charlie E. wrote: >>>>>>>> On Mon, 26 Oct 2009 23:00:28 +0000, Martin Brown >>>>>>>> <|||newspam|||@nezumi.demon.co.uk> wrote: >>>>>>>> >>>>>>>>> Joerg wrote: >>>>>>>>>> ChrisQ wrote: >>>>>>>>>>> Joerg wrote: >>>>>>>>>>>> On the news a few days ago: They had to close the "environmentally >>>>>>>>>>>> compliant" new wing of a school because of H1N1. The old (real) >>>>>>>>>>>> buildings exhibited little problems because you could open windows, >>>>>>>>>>>> "hallways" were outdoors, etc. The newfangled building was >>>>>>>>>>>> essentially a giant petri dish and so the kids there got sick. So >>>>>>>>>>>> much for progress. >>>>>>>>> That is a weakness of a lot of the no external opening windows designs. >>>>>>>>> Sick building syndrome as the formaldehyde and other junk from the >>>>>>>>> furniture and carpets accumulates in a poorly ventilated space. There is >>>>>>>>> no excuse for not having fresh air heated by outgoing stale air though. >>>>>>>> <snip> >>>>>>>> >>>>>>>> My home here (three years new) has not only double pane windows, it >>>>>>>> also has plastic sealing in all the exterior walls. In a 70 mph wind, >>>>>>>> there are only a few places where I can feel a draft - one by a wall >>>>>>>> outlet, and the other around my back door. The door flexes enough to >>>>>>>> release the weather stripping! >>>>>>>> >>>>>>>> But, my HVAC system also has a timer that causes it to go on with the >>>>>>>> fan only at least every so often, and the system has an intake to the >>>>>>>> outside for fresh air. ... >>>>>>> I've always wondered where to get those. It would need to be before the >>>>>>> filter or have its own filter. This whole concept of whole house fans is >>>>>>> so strange, they rely on venting out instead of in so all the dust and >>>>>>> pollen is sucked into the house. In Australia there are (IIRC) systems >>>>>>> that blow in instead, makes a lot more sense. Never seen that in the US. >>>>>> I put one in my NY house. It worked. We didn't have AC so between >>>>>> the whole house fan and pool we survived. ;-) The key to the whole >>>>>> house fan was blowing the attic out in the evening and cooling the >>>>>> house down. We then closed it up during the day. If you're going to >>>>>> have windows open at all you'll have pollen in the house. I prefer >>>>>> windows open, if possible. I certainly don't want the dust and >>>>>> insulation from the attic in the house! >>>>>> >>>>> All you'd have to do there is lay a duct to the end of the attic, then >>>>> put the fan and a filter there. But nobody makes them :-( >>>> Never made your own ductwork? When I was a kid in Jr. High and High >>>> School, sheet metal shop was a requirement for all males (before equal >>>> rights... the girls had to take Home Economics ;-) >>>> >>> Sure I did. But you can't get the proper fans with filters up front. I >>> mean a kind that would pass inspection. >> >> You're putting the filters in the wrong place. >> >> (1) EXHAUST blower in attic blowing out an external vent. >> >> (2) Electrically-controlled louver to connect to interior AC ductwork, >> sucking house air out into attic, then to outside world. >> >> (3) Inlet to interior of house from outside, somewhere (me, I might >> just cut a "window" in the side of the house ;-) outfitted with >> filter(s). >> >>> >>>>> I was thinking about a 6" or 8" inline fan and making my own filter. But >>>>> I doubt that's going to be even close in terms of required airflow. >>>> Since this would be at mild weather and/or attic exchange rate, I'd >>>> guess a 1000-2000CFM squirrel cage would do it. I'd probably use 4 >>>> 20"x30" A/C filters (in an array). >>>> >>> Pleated filters in an array for outside air intake would get expensive. >>> At least around here. >> >> So use cheapy fiberglass. (Pleated might not pass enough air anyway.) >> > >So, essentially then you made a whole house fan with a hole in the house :-) > >Problem with that, huge: Someone goes out the patio door, only closes >screen or leaves it all open. Speaking in electrical terms the >transconductance of that screen is much higher than that of your hole, >meaning most of the filter gets bypassed, meaning yellowish greenish >pollen everywhere. All my back yard doors are "pool-proof". Get over it, you just don't know how to make it work ;-) ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | "Somebody had to build the ceiling... before Michelangelo could go to work." - John Ratzenberger http://analog-innovations.com/SED/Somebody_had_to_build_the_ceiling.pdf
From: Joerg on 29 Oct 2009 17:49 Michael A. Terrell wrote: > Joerg wrote: >> Michael A. Terrell wrote: >>> Joerg wrote: >>>> Easy with a mechanical timer if needed. But that's what the CD4060 was >>>> invented for. Maybe that's too difficult for a HVAC mfg ... >>> >>> Mechanical timers ignore power outages. >>> >> You can make both do either/or. Mech times with li'l tic-toc movement in >> there, got one of those here. A CD4060 can be run off a large cap for a >> looong time. If designed right, and that's the trick. > > > I prefer the mechanical design, because of the high number of > lightning strikes around here. If you want to sign off on a CMOS > design, go ahead. Its your reputation, not mine. > I did a while ago. Most of it is installed in your neck of the woods. Works great, it's through two seasons now. One must understand the mechanisms, paths, spectra and remedial action when it comes to lightning. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joerg on 29 Oct 2009 17:51
Jim Thompson wrote: > On Thu, 29 Oct 2009 13:37:09 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> Jim Thompson wrote: >>> On Thu, 29 Oct 2009 11:28:50 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: >>> >>>> Jim Thompson wrote: >>>>> On Thu, 29 Oct 2009 11:10:28 -0700, Joerg <invalid(a)invalid.invalid> >>>>> wrote: >>>>> >>>>>> krw wrote: >>>>>>> On Tue, 27 Oct 2009 11:16:29 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>> wrote: >>>>>>> >>>>>>>> Charlie E. wrote: >>>>>>>>> On Mon, 26 Oct 2009 23:00:28 +0000, Martin Brown >>>>>>>>> <|||newspam|||@nezumi.demon.co.uk> wrote: >>>>>>>>> >>>>>>>>>> Joerg wrote: >>>>>>>>>>> ChrisQ wrote: >>>>>>>>>>>> Joerg wrote: >>>>>>>>>>>>> On the news a few days ago: They had to close the "environmentally >>>>>>>>>>>>> compliant" new wing of a school because of H1N1. The old (real) >>>>>>>>>>>>> buildings exhibited little problems because you could open windows, >>>>>>>>>>>>> "hallways" were outdoors, etc. The newfangled building was >>>>>>>>>>>>> essentially a giant petri dish and so the kids there got sick. So >>>>>>>>>>>>> much for progress. >>>>>>>>>> That is a weakness of a lot of the no external opening windows designs. >>>>>>>>>> Sick building syndrome as the formaldehyde and other junk from the >>>>>>>>>> furniture and carpets accumulates in a poorly ventilated space. There is >>>>>>>>>> no excuse for not having fresh air heated by outgoing stale air though. >>>>>>>>> <snip> >>>>>>>>> >>>>>>>>> My home here (three years new) has not only double pane windows, it >>>>>>>>> also has plastic sealing in all the exterior walls. In a 70 mph wind, >>>>>>>>> there are only a few places where I can feel a draft - one by a wall >>>>>>>>> outlet, and the other around my back door. The door flexes enough to >>>>>>>>> release the weather stripping! >>>>>>>>> >>>>>>>>> But, my HVAC system also has a timer that causes it to go on with the >>>>>>>>> fan only at least every so often, and the system has an intake to the >>>>>>>>> outside for fresh air. ... >>>>>>>> I've always wondered where to get those. It would need to be before the >>>>>>>> filter or have its own filter. This whole concept of whole house fans is >>>>>>>> so strange, they rely on venting out instead of in so all the dust and >>>>>>>> pollen is sucked into the house. In Australia there are (IIRC) systems >>>>>>>> that blow in instead, makes a lot more sense. Never seen that in the US. >>>>>>> I put one in my NY house. It worked. We didn't have AC so between >>>>>>> the whole house fan and pool we survived. ;-) The key to the whole >>>>>>> house fan was blowing the attic out in the evening and cooling the >>>>>>> house down. We then closed it up during the day. If you're going to >>>>>>> have windows open at all you'll have pollen in the house. I prefer >>>>>>> windows open, if possible. I certainly don't want the dust and >>>>>>> insulation from the attic in the house! >>>>>>> >>>>>> All you'd have to do there is lay a duct to the end of the attic, then >>>>>> put the fan and a filter there. But nobody makes them :-( >>>>> Never made your own ductwork? When I was a kid in Jr. High and High >>>>> School, sheet metal shop was a requirement for all males (before equal >>>>> rights... the girls had to take Home Economics ;-) >>>>> >>>> Sure I did. But you can't get the proper fans with filters up front. I >>>> mean a kind that would pass inspection. >>> You're putting the filters in the wrong place. >>> >>> (1) EXHAUST blower in attic blowing out an external vent. >>> >>> (2) Electrically-controlled louver to connect to interior AC ductwork, >>> sucking house air out into attic, then to outside world. >>> >>> (3) Inlet to interior of house from outside, somewhere (me, I might >>> just cut a "window" in the side of the house ;-) outfitted with >>> filter(s). >>> >>>>>> I was thinking about a 6" or 8" inline fan and making my own filter. But >>>>>> I doubt that's going to be even close in terms of required airflow. >>>>> Since this would be at mild weather and/or attic exchange rate, I'd >>>>> guess a 1000-2000CFM squirrel cage would do it. I'd probably use 4 >>>>> 20"x30" A/C filters (in an array). >>>>> >>>> Pleated filters in an array for outside air intake would get expensive. >>>> At least around here. >>> So use cheapy fiberglass. (Pleated might not pass enough air anyway.) >>> >> So, essentially then you made a whole house fan with a hole in the house :-) >> >> Problem with that, huge: Someone goes out the patio door, only closes >> screen or leaves it all open. Speaking in electrical terms the >> transconductance of that screen is much higher than that of your hole, >> meaning most of the filter gets bypassed, meaning yellowish greenish >> pollen everywhere. > > All my back yard doors are "pool-proof". Get over it, you just don't > know how to make it work ;-) > We have three dogs now. The two older ones know how to open doors and the young one is a smart cookie, always attentively watching the others. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |