Pellet stoves, humidity and OAK

[HP52NOVA]

This is our first season burning pellets. A few years ago we installed a whole house humidifier as it was getting very dry during the winter time (this is before the stove was installed). Over the years, I kind got a benchmark on how much that humidifier would work in a season. We just had the second canister replaced on it this year, and the humidifier seems to be working about 25%- 35% more than during any other season. It is setup on “automatic” mode to regulate RH level per temp outside (April Air 800). My house is larger than average, but also fairly insulated (newer construction).

So here are the questions:
Is it normal that a working pellet stove would cause this effect? It just seems to be drying the air a lot more than our propane furnace and heat pimp use to do. Why is that?
Does the fact that we have an OAK (outside air intake) on the stove matter at all? Is that air getting in the house somehow causing the humidifier and stove to be in constant battle?
Is there anything we can do to improve the issue?

 

[TimfromMA]

OAK air is only used for combustion so it wouldn't have an effect on humidity.

 

[TonyVideo]

OAK has no effect as air is transfered in and out without contacting inside air. It is the high temp of the stove in one general area probably close to your humidity adjustment causing it to run more. Furnace distributes the heat more evenly with the humidified air. Where is the humidity sensor in relationship to your stove? Hotter the air the dryer it will be. Heat pumps generally are 10-15 degrees warmer from the vents than the internal air temp so do not dry out the room as fast.

 

[alternativeheat]

Actually if you had no OAK it would dry the air even more. At least with OAK the stove is feeding on and burning up what humidity there is in the air from outside rather than inside. But yes, stoves in general lower humidity levels in the house. Think about it, your convection blower is drawing in house air and heating it, no water added and pushing out dry air. If you had no OAK then combustion would additionally be taking in house air and burning it , then throwing it up the chimney outdoors.

The solution ? Add more water , humidify.

A forced hot air central heating system isn't much better btw. We are having very cold temps this winter, that generally brings along with it low relative humidity. At least around here in NE on the cold dry days with no storms around..

 

[HP52NOVA]

OAK has no effect as air is transfered in and out without contacting inside air. It is the high temp of the stove in one general area probably close to your humidity adjustment causing it to run more. Furnace distributes the heat more evenly with the humidified air. Where is the humidity sensor in relationship to your stove? Hotter the air the dryer it will be. Heat pumps generally are 10-15 degrees warmer from the vents than the internal air temp so do not dry out the room as fast.

The tstat controlling the furnace and humidity is on the other side of the house. it can read 30% RH on it, while next to the stove we only get 20%. it certainly seems its running dryer then either the furnace or the HP

 

[HP52NOVA]

Actually if you had no OAK it would dry the air even more. At least with OAK the stove is feeding on and burning up what humidity there is in the air from outside rather than inside. But yes, stoves in general lower humidity levels in the house. Think about it, your convection blower is drawing in house air and heating it, no water added and pushing out dry air. If you had no OAK then combustion would additionally be taking in house air and burning it , then throwing it up the chimney outdoors.

The solution ? Add more water , humidify.

A forced hot air central heating system isn't much better btw. We are having very cold temps this winter, that generally brings along with it low relative humidity. At least around here in NE on the cold dry days with no storms around..

thanks, I guess this is normal then. I will have to factor in another canister per year for that humidifier! comparing forced hot central air to the pellet stove, I would say the stove is running at least 25%- 35% drier - this is just looking at run time and water intake. on a very cold day , just with the furnace the humidifier may not even come on due to the frost protection feature. with the pellet stove its on 24/7.

 

[moey]

If your pulling in more combustion air then you were before you house could have a lower humidity. The leakier the house the drier it is. Your leak is air for combustion. A OAK may help. The stove does not dry out air in any way. It causes additional leaks for combustion air.

 

[HP52NOVA]

If your pulling in more combustion air then you were before you house could have a lower humidity. The leakier the house the drier it is. Your leak is air for combustion. A OAK may help. The stove does not dry out air in any way. It causes additional leaks for combustion air.

But I already have an OAK, and we certainly see a difference when the stove is running vs. when the furnace or the HP were. So why are we more dry with the stove then without? It seems that there is something in the way the stove process the distribution air that's drying it.