Peace Lily does best in locations with moderate light (close to a sunny window or directly in front of a window that doesn't get much direct sun, or under grow lights if natural light is insufficient). They prefer to stay a bit more evenly moist than the average houseplant, though they don't need to stay wet, and like other houseplants, any saucer used under the pot should be emptied promptly after collecting drained water so the excess doesn't seep back into the drain holes. (If the plant is in a pot without drain holes, consider transplanting it into one that does.) Moderate ambient humidity is ideal (maybe about 50% relative humidity), though not always achievable in winter unless a humidifier is run nearby. Keep them away from chilly drafts (and even warm drafts like that from a radiator, fireplace, or heat vent).

The bit of leaf edge browning/drying visible in the photos suggests that minor stress from soil moisture (maybe getting too dry between waterings, but it's hard to tell) or low humidity, or the draft you mention, may be causing the damage. Peace Lily is also known for being sensitive to a soil buildup of tap water additives like fluoride, though usually we see leaf tip browning in that case, rather than browning along one edge. It's normal for aging leaves to dry out and fall off, and they can be clipped off as they turn yellow and brown.

If you have fertilized the plant regularly in past months, stop fertilizing during winter, as indoor plants generally grow so little during these short days that they don't need the extra nutrients. Over time, unused nutrients can also build up in the potting mix and stress or damage roots, so every few years (how often really depends on various conditions...maybe every 1-3 years) repot the plant to refresh the soil by taking off much of the old mix and replacing it with fresh.

Aside from that somewhat minor leaf damage, the rest of the plant looks pretty good. Going forward, to avoid over-watering or under-watering, rather than watering on a set schedule, check the pot periodically to see how frequently it's drying out enough to need watering. Feel the soil about 1-2 inches deep into the container and water thoroughly once it becomes somewhat dry to the touch at that depth. By waiting until the soil dries out enough to need wetting again, you're helping to ensure the roots get enough oxygen to stay healthy (the wetter the soil stays, the less air can exist in the pores between soil particles, and roots need to "breathe").

Miri