seb@mtgzy.UUCP (s.e.badian) (02/15/86)
I have gotten to the point where I cannot survive in a house that is too dry, not to mention what it does to my houseplants. While living in a apartment a large room humidifier managed to keep the whole place at a reasonable humidity level all winter long. Now that I've moved into a house, the thing just does not do the trick. We have a oil fired furnace and I would like to get a furnace humidifier for it. Anyone out there care to recommend brands? Can we install it ourselves or should we call the people who service our furnace? Any words of wisdom for the multitudes would be appreciated. Sorry to bother you folks in the damp South and Northwest with this query. I don't think you folks have to worry about drying out. (Being taken over by slugs, maybe. :-)) Sharon Badian ihnp4!mtgzy!seb
tower@mit-prep.ARPA (Leonard H. Tower Jr.) (02/21/86)
Our plumber recommended against this on the grounds that the ducts
would rust out with time, particularly at the joints where there is
iron unprotected by the covering galvanization.
He suggested pans of water on the grills instead.
We also:
- vent the dryer into the house in the winter.
- hang damp clothes on rack (mostly in the DR, but your choice).
- leave the sink and tub fill of the hot water from dishes, a shower
or a bath, until it cools.
- have some house plants.
This is sufficient to keep the house above 50% relative humidity on
the coldest, dryest days here in New England. There is also no
maintenance headache on the furnace humidifier.
Len Tower
Project GNU of the Free Software Foundation
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INTERNET: tower@prep.ai.mit.edu
ORGANIZATION: Project GNU, Free Software Foundation,
1000 Mass. Ave., Cambridge, MA 02138, USA +1 (617) 876-3296
HOME: 36 Porter Street, Somerville, MA 02143, USA +1 (617) 623-7739
--
Len Tower
Project GNU of the Free Software Foundation
UUCP: {}!mit-eddie!mit-prep!tower
INTERNET: tower@prep.ai.mit.edu
ORGANIZATION: Project GNU, Free Software Foundation,
1000 Mass. Ave., Cambridge, MA 02138, USA +1 (617) 876-3296
HOME: 36 Porter Street, Somerville, MA 02143, USA +1 (617) 623-7739res@ihlpl.UUCP (Rich Strebendt @ AT&T Information Systems - Indian Hill West; formerly) (02/23/86)
> Our plumber recommended against this on the grounds that the ducts > would rust out with time, particularly at the joints where there is > iron unprotected by the covering galvanization. > He suggested pans of water on the grills instead. I would take the plumber's advice on a heating/cooling problem about as much as I would take his advice on a cardiac problem. The house we are living in has had an Aprilaire humitifier in it ever since it was built 20+ years ago. I have seen NO problem of rust in the duct work despite the fact that this is a ranch-style house with long runs of ductwork in the crawlspace. Perhaps the ducts will rust -- in a century or two. > This is sufficient to keep the house above 50% relative humidity on > the coldest, dryest days here in New England. There is also no > maintenance headache on the furnace humidifier. Do you have a good growth of mold on your walls? A relative humidity level of 50% is 'WAY too high. At around the freezing point outside you should have about 30% relative humidity, with the desirable level of humidity declining as the temperature declines. It IS important to maintain a decent humidity level in a house for comfort and the feeling of warmth with the house at a reasonable temperature, but too much humidity can be damaging. If you are getting a fair amount of condensate on you windows on a cold day you probably have the humidity level too high. Rich Strebendt ...!ihnp4!iwsl6!res
msb@lsuc.UUCP (Mark Brader) (02/26/86)
Leonard H. Tower Jr. (tower@mit-prep.ARPA) writes: > Our plumber recommended against this on the grounds that the ducts > would rust out with time ... > iron unprotected by the covering galvanization. I would suspect that it would take a very long time before this was significant. After all, even a duct with a little rust in it will carry warm air. And a humidifier on the furnace gives you *central* humidification, which is not to be sneezed at. Leonard goes on to itemize the "homemade" humidification that he uses, and concludes with: > This is sufficient to keep the house above 50% relative humidity on > the coldest, dryest days here in New England. According to my references, Leonard is risking his *walls*. This is a dangerously high humidity. One source (the maker of our humidistat) recommends the following settings: Outside temperature (C) 0 -5 -10 -20 -25 -30 (F) 30 20 10 0 -10 -20 Relative humidity 40% 35% 30% 25% 20% 15% [I know the C/F conversions aren't exact. Actually we were only given C, but the unequal intervals suggested that it was converted from the F line shown and then rounded to multiples of 5 degrees C.] In any case, if there is condensation on the windows, it is too humid. Our house is not at all "tight", and on a cold day our furnace humidifier delivers only about 10% relative humidity anyway. (Right now it's 8% with a breezy -10C outside.) This is almost enough for me anyway; I personally like about 15% humidity. But if you like more, and you have a leaky house, a furnace humidifier won't have enough capacity for you. Mark Brader
dkatz@zaphod.UUCP (Dave Katz) (03/07/86)
If you have leaky walls, then when the temperature is below freezing the excess humidity will penetrate the walls and form ice inside the (hopefully) insulated space. The result is lost R-value ( insulating strength) in the short term leading to higher fuel bills, and trapped moisture in the longer term leading to wood rot. In any house that does not have a very sound vapor barrier, the humidity should be kept as low a tolerable during the winter. The manufacturers recommended humidity settings are little more than the maximum humidity that can be supported in a house with double glazed windows without getting condensation on the glass. This may be indicative of what is going on elsewhere in the structure. In a well sealed house with triple glazing, the recommendation would be for and RH of about 39.2% when the outside temperature is -40 and inside is "comfortable" (around 72F or 22C) D.K.