I’ve been in Vegas for about a month. The first few weeks I spent at a different place, and it was warm enough that no heating was required. I’d usually wake up pretty dry, enough to make my throat rough, but not enough to be extremely uncomfortable.
I’ve moved into an apartment with a gas furnace, and now I wake up 4-5 times a night because my entire skull is a desert. By the time I get up in the morning, it feels like there’s not a drop of moisture in me. Does the extra dryness I’ve experienced since coming here come from the gas furnace?
In any case, I suppose I’ll have to get a humidifier, I’m just wondering if it’ll get better in seasons when I don’t need the heater.
Any type of heating which doesn’t add any moisture to the air will lower the relative humidity. How much will depend on the RH of the ambient air, and the temperature rise. The lower the RH to begin with and the greater the temperature difference between the outdoor air and the indoor air, the drier it will be inside. A humidifier is your best bet for comfort.
Typically the dryness of Winter is due to the fact that the outside air is already dry, especially if below freezing… But another part of it is the difference between relative humidity and absolute humidity. All else equal, air at 40 F and 50% RH does not contain the same moisture as air at 75 F and 50%, it contains less. How much less is easy to calculate online, or graphically using a psychrometric chart. Overall, the absolute humidity often ends up being less in the Winter, so you end up being dryer.
Now go to 40 F dry bulb (the bottom axis) and 50% RH (the curvy lines), and read over to the right-hand side - you’re roughly at 0.0025 pounds of water per pound of dry air. Now slide on up to 75F dry bulb along the curvy 50% RH line, and when you read across to the right, you’re at about 0.0095 pounds of water per pound of dry air.
Now instead, go back to the 40F and 50%RH point, and move horizontally to the right, until you get to 75 F - now read the curvy line, and you see your RH is about 13% RH. This roughly simulates taking outside air at 40F/50%RH and heating it to 75F with no humidification added. Ouch.
Whether or not it’s gas or electric heat may not matter so much, depending upon the furnace design (I could stretch and make an argument for peak versus mean temperature during the heating process, but I don’t know if it’s relevant), but the major factors may be instead 1) is there a humidifier on the unit, and 2) what portion of outside air infiltrates to dry out the house.
You have to remember that Las Vegas is in the middle of the desert and is bound to be dry.
Before you go out and spend money for a humidifier, try this trick. Place a pan of water in your bedroom near the heat vent. Refill it every few days and see if this doesn’t help.
Just to point out that some gas heaters are ventless and will add humidity from combustion of gas. I don’t know if they have whole house ventless gas furnaces, but some places have rooms with gas ventless space heaters.
