: Humidity too low in house
2008-11-28, 11:23 AM
My first post, just found this forum and it looks great.
O.K. 3 bedroom cottage in Montreal and when it gets cold out,
the huidity reads as low as 24/25 at worst. It seems to be really dry all winter. House built in the late 50's. Been here for 5 years, just replaced the windows last month and insulated the attic, but it does not seem to be helping any. The old style drum humidifier attached to the furnace seems to be running o.k. It comes on every time the furnace kicks in.
The funny thing is , I moved here from my old house, which was on the same street, built the same time, same style, same furnace, same humidifier and if i moved the dial up a bit in the old house, I would get condensation on the windows, it was like a hair trigger. Now I have it turned up full, and I cant seem to get any humidity. Any ideas. Thanks guys
Mike in bloody cold Montreal
1. Insulation is only part of the issue. It's whether the house is properly sealed or not that's the major factor. The amount of air infiltration that you have may be too much for the humidifier. You could perhaps get an energy audit or if you know where you've got some leaks - seal them. This is the highest payback item you can do in most houses - this will help with your energy bills as well as your humidity.
2. Most humidifiers are connected to the furnace fan control, not the furnace control, so you could try turning on the fan full time as this will have the humidifier working more than only when the furnace comes on.
2008-11-28, 11:38 AM
Good tip, I will try running the fan full time. Thanks
I had the energuide for houses done before I got the new windows.
I had sealed up the cracks pretty good already, but he let me know of a few more places, of which I have yet to seal. It seems to me that it is something else though. It is like night and day from my old house yet every thing is just about the same. I feel like I am overlooking something, like the humidifier is not doing its job, or is not in a good location, but it seems o.k.
2008-11-28, 12:18 PM
Check that it actually is running with only the fan running, some are wired just to run when the heat is running. It all depends on the installer and the type of furnace.
2008-11-28, 02:18 PM
Make sure there's actually air blowing over the humidifier pad. Some humidifier setups have a high/low or on/off dial that controls a damper in the hot air line. The idea is to shut off the air flow in the summer so that you're now blowing cold AC air through the humidifier into the cold air return.
Perhaps it's working fine but just not getting enough warm air moving across it to bring up the humidity.
If you've been there for 5 years did it work last year? Perhaps you need a new humidifier pad/filter?
2008-12-01, 02:31 PM
I change the filter each year.
I open and close the damper per season.
Hot air seems to be passing through the pad.
The humidifier does not work in the fan only mode.
As everything seems to be working, I don't really want to buy a new one in case it does not work any better.
Do you think I would have better luck with the new style
where the water drains?
2008-12-01, 03:41 PM
Yes, you have a drum humidifier? The Flow throughs are much better and easier to keep clean.
2008-12-02, 09:53 AM
I checked my user manuals and discovered that the furnace connection point for the humidifier to come on when the heat is on operates at 24v, and at 120v for the humidifier to operate when just the fan is on, ie without heat. This means I will need an additional relay for the fan on scenario, as the humifier is 24v.
Right now, the max humidity I can get is 33 or 34%, which is a little too low.
I am a little concerned whether running water 24 hours a day will waste too much of it and am thinking a control valve in the water supply line is a good idea, so I can turn down the volume of water going through the humidifier.
2008-12-02, 10:18 PM
you can just partially close the water feed vavle. No need for anything complex.
2008-12-09, 12:00 AM
You say you have new windows so that will certainly make a difference on how much condensation may form. New windows mean better insulated windows and less condensation and you really do not want moisture on the windows anyway. 35% is just about right in the cold of winter. Humidy levels should be set to 35% or less when the outside temp gets below about -10c. The other thing is that if you do not have heavy window treatments, the windows will not get as cold therefore will show less condensation.
As for the flow through types of humidifiers, they are huge water wasters in general and many municipalities are trying to get rid of them. There are some better style units out there now - Spring Aire comes to mind, that are drum style but do not use pads and have as good as or better performance then the pad types.
Lastly, a lot of the humidity in a house also comes from cooking, showering, laundry etc and if there is less of that going on then that would also reduce humidity.
Is your humidistat in the cold air return or in the living space? If the humidistat is too close to the humidifier it could be shutting down too soon.
2008-12-10, 05:24 AM
What is the outside temp? On the prairies in winter 35% was sometimes too much humidity.
In BC where we are we dehumidify to 35% and it is comfy to us.
2008-12-10, 10:42 AM
My humidistat is on an inside wall on the main floor and the humidifier
is in the basement on the furnace. I have no problem with condensation, that was someone else in a reply in this thread. He has too much humidity, me not enough. I thought the new doors and windows and added insulation in the attic would help, but it has not helped at all. I arrived home from work the last 2 days and my reading was " LOW " which means below 25%. It has been cold though, like - 18c. We are a family of 4 , 2 kids , four showers a day, lots of cooking and laundry. We do not even use our bathroom or kitchen fans to try and keep in a bit of humidity. Thanks for all the info guys,
keep it coming!!
2008-12-10, 06:59 PM
ctrider.. What temp do you keep your house at? Your indoor RH is a function of your indoor temperature. The warmer you keep your house the lower your RH is going to be. If you're keeping the house warm and your outdoor temp is really low then you'll end up with lower humidity levels. Conversely, the lower the indoor temp the higher your RH is going to be.
If you're still having low RH issues, I would recommend looking into a newer Steam Humidifier, they're making them for residential applications now. I'm sure one of those would maintain your humidity at whaterver you like.
Edit, I forgot to ask, have you checked the calibration on your humidistat? They're not really finely tuned and vary widely.
the max humidity I can get is 33 or 34%, which is a little too low.
Any higher than that and you'll get condensation on windows.
The ultimate cure it all rules of thumb for humidity problems in cold climates:
- If relative humidity is too high, increase ventilation
- If humidity is too low, do everything you can to reduce infiltration (Draft proof!)
The psychometric chart never lies...
A humidifier is simply a crude patch for too much air leakage. Steam humidifiers are expensive to operate and most likely scale up quickly, flow through units waste enormous amounts of water, and drum humidifiers are just plain nasty.
2008-12-11, 12:19 AM
I agree with you TXV, in a perfect world we wouldn't need Humidifiers, but the fact remains that Humidifiers are needed in a lot of residential applications, otherwise there wouldn't be a thriving market for them. As for the Steam Humidifier, The Honeywell TrueSteam unit is a lot more efficient and cleaner than most drum type and even flowthrough humidifiers. It's self cleaning/flushing and under normal usage can be cleaned by the homeowner, two steps to take it apart and it can be run through the dishwasher once a year. Granted you're going to pay more for hydro to run it, but a 6 gallon/day unit would run at 840 watts. The fact that it's providing pure steam directly into the supply duct means it'll humidify faster than a flowthrough or drum. This also helps in situations where the furnace run times are short and you don't have enough time to get the humidity before everything cycles off.
2008-12-12, 10:45 AM
WGAUCI , I keep my temp at 70 , but for the most part it is down at 62, overnight and during the day. I guess that should help the humidity when the furnace is not running, but as well the humidifier is not working when the furnace is not running. Dammed if you do, dammed if you don't. haha.
For the calibration of the humidistat, it is always at full, as my humidity is too low. Whenever the furnace rums, the humidifier is on.
Do you know if any of the big box hardware stores sell the Honywell steam unit? And for around how much, as well what would I expect to pay for an installation. Thanks very much.
Yesterday was a reading of 19%, my knuckles are dry, have started to crack and bleed. Happens every year. Doesn't help that I am a diabetic with naturally dry skin, and work in a building that is 130 years old with low humidity as well, LOL
2008-12-12, 04:41 PM
I don't know of any big box stores that might carry them, I only started seeing the Honeywell model in the trade supliers I frequent at the start of this season. If I had a choice, I would invest in having an experienced pro. install it and set it up for you. I have gone through the installation manual, the TrueSTEAM HM series wire into the furnace and will take over fan control on a call for humidification. This will allow you to humidify your house even when you're not calling for heating. Because you're using steam, you don't need the furnace running to help evaporate the water in your drum or pad type, though you can do this with an evaporative humidifer, the steam is going to be a lot more effective with no heat running to help evaporate the moisture. Also because the steam is injected into the supply duct it's not passing into the return, through the filter, heat exchanger and coil before it makes it to the supply duct. This is a lot more effective and how most all commercial humidification is done. Another added bonus is you can have this remote mounted up to 20 ft. away from the point your injecting the steam into the ductwork which can make installing the drainage line easier.
If it's becoming a health and comfort issue with you, i'd recommend getting something like this done.
2008-12-14, 04:20 AM
Have you changed the humidifer pads or plates? They can get clogged up and not carry water into the air stream.
I notice you "change the filter every year" Is that the drum pad or plates???? If drum is it soaked as it rotates?
It is a pad not a filter.
Is the flow correct. Connected return to hot air?? and is the air flowing?
2008-12-14, 11:08 AM
My home was built in the 80's and is well insulated and sealed. The humidity usually runs around 35%. I heat with a woodstove in the basement and an electric furnace. I just removed the drum humidifier and tossed it as it hadn't worked for several years.
I have found that heat from electricity(furnace or baseboard) does not tend to add or remove humidity. Natural gas on the other hand tends to add humidity particularly if the cook stove is gas. Oil furnaces and wood burners tend to remove humidity.
In my situation, I placed a "cool mist" humidifier on the main floor(high ranch bungalow) and it runs 24 hrs. I seem to be filling the reservoir once each day which can be a pain. I have also found that cleaning the evaporator pad once a month helps. I am on well water and the minerals cake on the pad. White vinegar does the job of cleaning the pad. The unit I have is one of the larger ones and it holds approximately 1.5 gallons. It seems to maintain the humidity in the house at from 30-40% depending on the temp and RH of the outside air. I also have a kettle of water on the woodstove at all times.
My son heated with oil in his previous home and his wife works for a heating and a/c contractor. He had extremely dry conditions and replaced his drum humidifier with the flowthrough type. This dramatically improved his situation and the wasted flow did not present a problem for him.
I think the portable humidifier may the the cheapest solution even if it is not the most convenient.