Baseboard heating - our house is really dry and I am trying to figure out why

adam061712

We purchased a house built in 1956 last year. We have baseboard heat with a gas boiler. The boiler is newer from 2001. Now that we are going through our second winter we are realizing this house is SUPER dry. My son and I are waking up with bloody noses every day and we both have humidifiers in our bedrooms. The house also has all new windows that were put in before we purchased the house and our gas bill is very low. I am trying to figure out what is causing the dryness. Any thoughts? We recently learned that our boiler has to heat water to 200 degrees instead of the normal range of 160-180 degrees. We turned the boiler down to 180 and it could not heat the house more than 66 degrees. Could the fact that we have to heat the water to 200 degrees be contributing/causing the dryness? I am trying to decide if we should install a whole house humidifier -Aprilaire 350 but there are mixed reviews that it does not really help that much. Since we don't have ductwork like an HVAC house there is not a good place to put it on the 1st floor of the house that provides good access to the 2nd floor which is where we need the humidify. Any insights is greatly appreciated.

pecmsg

The heat has nothing to do with low humidity levels. Air infiltration is your problem.
Have a Blower Door Test done to locate where the outside air is coming in and escaping from. Correct those problems and get a whole house humidifier.
Fuel usage will go down and humidity levels will settle down

JUGHNE

What type of chimney does your boiler use?

ChrisJ

Like @pecmsg said, types of heat, boilers, furnaces etc have nothing to do with how dry the air is. Sucking in cold outdoor air and warming it up does.

The colder it is outside, and the draftier your house is, the dryer the air inside will be. My 150 year old house with mostly original windows has been a crunchy 20% for a while, though for all I know it could be lower and the cheap hydrometers aren't showing it.


Humidifiers will help assuming they can bring you up to a comfortable 40-50% RH. Are your humidifiers doing this in the bedrooms? Also, keeping the bedrooms cooler will help a lot. I keep my house at 72F but my bedrooms at 64F using TRVs.

adam061712

Thanks @pecmsg this is helpful stuff. I was thinking of doing a Blower Door Test. However, my house really is not drafty at all. Considering we have all new windows there are really no drafty areas. I also looked into having a Blower Door Test and they are kind of pricey and it is hard to find someone who does them.

JUGHNE

If you have the typical chimney set up on your boiler (not a 2 pipe PVC ModCon boiler), then there may be a constant air flow up the chimney which sucks in cold dry air probably thru basement leaks, gas water heater also adds to this.
The more exhaust air you push out of your house also brings in more air. Bath and range exhaust fans and also clothes dryer all contribute to the introduction of new outside air.
You may not feel drafts but there would be a lot of small leaks in a 1956 house IMO.

Where are you located that it takes 200 degree water to heat your house?

adam061712

@JUGHNE not sure what you mean. Could you elaborate when you say, "what kind of chimney?" We have a wood burning fireplace with a brick chimney.

adam061712

@JUGHNE We do have a typical chimney set-up on our boiler. Is there anything that can be done about the chimney if there is constant cold air flow up the chimney? We actually know from our home inspection that the boiler part of the chimney needs to be relined. We just haven't done it yet. Would that help solve the problem? If we have a Blower Door Test and they identify the small leaks you are referring to will they outline how to fix the problem in their report? Do I then hire a general contractor to come and seal up all the leaks?

adam061712

@JUGHNE - I forgot to mention we live in a suburb of Chicago.

ChrisJ

Does that wood burning fireplace have a damper in the chimney?

JUGHNE

Of course the fireplace damper should be closed if not in use.
They are usually by no means at all tight.
Some people have glass doors which helps, but typically that vintage gets air for wood burning combustion from inside the house, so doors would still allow air flow. Some resort to a solid panel over the front to stop all air flow.
Masonry fire places on an outside wall are a fixed heat loss for the room they are in.

Could you post some pictures of your boiler showing flue pipe and water piping. Include one of the water heater if possible.

adam061712

@JUGHNE here are the pictures of my boiler, water pipings, hot water heater and flue pipe.

JUGHNE

Your boiler appears to have a motorized damper on the flue. You should hear and see it rotate 90 degrees before the boiler fires. The basement flue set up for both appliances appears normal.

Have you tried the fireplace damper? You might see it with a mirror and good flashlight. Smoke or candle flame would show you how much air is passing up the chimney.

Back to the 200 degree water. Have you taken any covers off the baseboard heaters to see if the fins are clean. They have to freely allow air to pass thru the heater.
Just looking at your boiler pump, its seems small, but I'm not tuned in to BB heat that much. Maybe someone more familiar could advise you on how much pump you might need depending upon how much linear feet of BB heaters you have in the entire house.

Gordy

To the original poster what is your measured relative humidity?

When humidity is really down in the weeds you get a lot of static electricity shocks is this a problem?

ChrisJ

Gordy said:

To the original poster what is your measured relative humidity?

When humidity is really down in the weeds you get a lot of static electricity shocks is this a problem?

Bloody noses after sleeping rank lower on the scale than static.

Gordy

We don't know what the posters rh is. 30-35%?

I would consider that range normal?

Paul48

If you're burning wood in a conventional fireplace, you're sucking as much heat out of the house as you are putting in. Have a good quality insert put in, that draws its combustion air from outside.

ChrisJ

Gordy said:

We don't know what the posters rh is. 30-35%?

I would consider that range normal?

30-35% is on the low side. 40-50% I find to be more comfortable assuming your windows tolerate it.

My house right now, 26% and it's bad.
Not bad enough to get me to fire up the humidifier, because I've been lazy, but still bad.

Gordy

I guess I'm a little perplexed how some have low humidity issues in random construction situations.

My house is 1952 construction.

Windows original to the period double Hung with storms excellent condition.

4- masonary fireplaces two of which have chimney top dampers air tight. The other two are the original type. I burn fires in one mostly every other two days on average. Maybe 6 hours avg.
That damper is mostly open.

Three baths with fans
Kitchen exhaust fan.
Atmospheric boiler with damper.
Atmospheric water heater.
Clothes dryer

I never have to humidify. Humidity is always 30-35%

Two showers once a day sometimes twice.
Laundry every 3 days.
Normal cooking.

Basement humidity 38%

No bloody noses at this humidity level.

I have built two well sealed envelope homes.
Thermopane Windows, tyveked, visquine interior wall detail. Caulked to no end.
Both had one prefab fireplace, and normal bath ventilation.

They had forced air. Always a battle with humidity.

So I do not completely buy into infiltration as being the sole cause to low humidity issues.

Steve Minnich

pecmsg said:

The heat has nothing to do with low humidity levels. Air infiltration is your problem.
Have a Blower Door Test done to locate where the outside air is coming in and escaping from. Correct those problems and get a whole house humidifier.
Fuel usage will go down and humidity levels will settle down

Interesting thread and what makes it more interesting for me is the fact that I'm the contractor who quoted the humidifier. pecmsg - I agree with your assertion to a point but when you have a Category I appliance, it's using a significant amount of air for combustion. This air is then replaced, typically, via infiltration and around and around we go.

Performing a blower test is always a good idea and doing the required buttoning up of the envelope is too. But the story can't end there. Now you could have an appliance starving for combustion air so that air now has to be introduced either passively or by a Fan In The Can or something similar. So you just can't tighten it up and forget about it because now another issue has to be addressed.

njtommy

I don't know I was always under the impression heat dehumidifies and drys out the air.

ChrisJ

Gordy said:

So I do not completely buy into infiltration as being the sole cause to low humidity issues.

Fine.
Please explain another source of low humidity in a home.

We're all ears since you've argued this multiple times. I'd like to hear your thoughts.

ChrisJ

njtommy said:

I don't know I was always under the impression heat dehumidifies and drys out the air.

Raising the air temperature lowers the relative humidity.
This is the nature of the beast. It doesn't matter how you heat it. This is why bringing in 10-20F air and heating it to 70F results it a low RH.

Keep most if your warm air in and your breath, cooking and showers will keep RH fairly high.

JUGHNE

Are there any house finishes or furnishings that act like a desiccant?.......yea, like the cracker in the sugar jar?

One I can think of is particle board, but it swells up and would be noticed. Real wood dries out and shrinks. Good furniture gets loose and wobbly.

I also gauge by the static electric discharge walking across carpet and touching anything.

Nosebleeds could be the result of being outside or in a very dry building during the day. Maybe only shows up at night when laying prone??? and no open mouth breathing going on.

Just crazy theories....

Gordy

I'm asking the question for discussion Chris. But emitter type must play a role. High temp verses low temp.

If 75% rh 10 degree cold air infiltrates into a 70 degree envelope that same air rh becomes 7%.

If your indoor temp is 70 degrees 40% rh, and that air goes over a 180* emitter the RH drops significantly to 3%.

If you are the same 70* 40% rh with an 80* emitter the rh drops to 30%.

Go to the link and play with scenarios. Go to the bottom to the relative humidity calculator.

http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/relhum.html

ChrisJ

Gordy said:

I'm asking the question for discussion Chris. But emitter type must play a role. High temp verses low temp.

If 75% rh 10 degree cold air infiltrates into a 70 degree envelope that same air rh becomes 7%.

If your indoor temp is 70 degrees 40% rh, and that air goes over a 180* emitter the RH drops significantly to 3%.

If you are the same 70* 40% rh with an 80* emitter the rh drops to 30%.

Go to the link and play with scenarios. Go to the bottom to the relative humidity calculator.

Yes,
Until it cools back down at which time it's RH returns back to normal.

Gordy

Right, but as it gets colder out the heating system runs more right? So rads, or what ever emitter is higher temp,for longer periods, and air has more contact time.

Gordy

Keep in mind I'm not saying infiltration is not playing the bigger role. Just not the only role.

JUGHNE

It is obvious that put something in an oven and it will dry out.

Now, the dumb question: 70* 40%RH air passes over the 180* element and drops to 3% RH........where did the 37% go to?

Gordy

Into the building materials the 180 dried out

Gordy

Hey I found the calculator that tells you what happens to the air humidity brought in from outside. Not inside drawn over hot emitters but I applied the calculator as such.

JUGHNE

So that means the furniture won't fall apart....won't it eventually reach its dew point and start to sweat?

But seriously, 200 degree water, is that common for BB, things were usually over radiated in the 1950's. And he has new windows. Someone who knows should look at the single pump on the boiler. Just a gut feeling.
I'm in the same HDD roughly and get by with 128 degree SWT.

Gordy

I think the fins are dirty, or carpet/ furniture is blocking air circulation.

As,for,reasons on the humidity levels. We can theorize a lot of things, but I know in my experience I have been in tighter envelopes with struggles to keep a comfortable RH. Verses where I live now. The difference is radiant verses FA. Lived with baseboard but only 140awt

JUGHNE

The fins were mentioned above, especially if previous owner had cats. The OP may have changed channels as this discussion might not seem to offer much more help...maybe tomorrow.

ChrisJ

JUGHNE said:

It is obvious that put something in an oven and it will dry out.

Yes,
Stuff in the oven drys out when the water is cooked out of it, not really the same thing.

Stuff placed in the refrigerator or freezer will also dry out. This is typically referred to as "freezer burn".

pecmsg

Stephen Minnich said:

pecmsg said:

The heat has nothing to do with low humidity levels. Air infiltration is your problem.
Have a Blower Door Test done to locate where the outside air is coming in and escaping from. Correct those problems and get a whole house humidifier.
Fuel usage will go down and humidity levels will settle down

Interesting thread and what makes it more interesting for me is the fact that I'm the contractor who quoted the humidifier. pecmsg - I agree with your assertion to a point but when you have a Category I appliance, it's using a significant amount of air for combustion. This air is then replaced, typically, via infiltration and around and around we go.

Performing a blower test is always a good idea and doing the required buttoning up of the envelope is too. But the story can't end there. Now you could have an appliance starving for combustion air so that air now has to be introduced either passively or by a Fan In The Can or something similar. So you just can't tighten it up and forget about it because now another issue has to be addressed.

Going off the OP's data a 1956 built home is not very tight. Short of stripping it down to bear walls and spray foaming everything floors, walls & ceiling there will always be some infiltration. Enough to feed the heater, stove, hot water demands? Enough to change the air over to meet minimum air changes required? Thats the reason for the testing. Its good practice to supply outside air to all fuel burning appliances.

Now when do you get to the point of to tight and the need for ERV's & HRV's is another discussion

njtommy

Humidity control is one of the reasons I do like forced hot dust, but that has major draw backs.

Most of the time even with a humidifier the furnace doesn't run long enough to humidifie the space do to over sizing and short run times.

Along with most people don't want to run the blower to humidifie the house with out a call for heat because the house feel cold and drafty.

ChrisJ

njtommy said:

Humidity control is one of the reasons I do like forced hot dust, but that has major draw backs.



Most of the time even with a humidifier the furnace doesn't run long enough to humidifie the space do to over sizing and short run times.



Along with most people don't want to run the blower to humidifie the house with out a call for heat because the house feel cold and drafty.

You can run much smaller duct work and run a much smaller fan to supply humidity and as well as dehumidify a building, no?

Basically, forced hot fudge still loses.

njtommy

Lol

You can run a lower blower speed to keep the drafty feeling down when humidifying the space

adam061712

Hi All - There have been a ton of questions so I am not sure where to start but here is what I can say..

- We have been using a portable house humidifier (AIRCARE). I usually set that to 45%. When it is not on the house is around 30% from what I can tell from the AIRCARE. That is the only way I can measure it right now.

- I have no idea why the house has to use 200 degree water. As I mentioned the guy that services my boiler discovered that it was set to 220 and turned it down to 180 and we could only heat the house to 66-68 degrees so now it is up to 200 and we can get to 70-72.

- The house has no carpets. It is all hardwood so we don't notice much "static electricity shock" as @Gordy mentioned. I know it seems that static is worse then a bloody nose but you wake up with a bloody nose everyday. I think you will think differently.

- We have literally NEVER used our fireplace since we bought the house so I have a hard time believing that is a main reason for our issues. The damper is shut but the chimney is old so I am sure it is not air tight. I put a candle in it and it did not appear to be leaking that much. I am sure it contributes to the problem but I doubt it is the root cause.

- I think I mentioned this before but our gas bill is CRAZY low. We went from 1200 square foot condo with HVAC to a 2400 square foot house with BB heat plus 1000 square foot basement and it costs about the same to heat. If anything it is cheaper to heat our house at times in the winter and cheaper to cool it in the summer then our old condo.

- Regarding the fins. The house is old and the BB are old probably original to the house. I have never taken off the covers and examined the fins. My guess is there regular dust on them (from 60 years) but as for them being blocked by furniture/carpet that is not the case. @Gordy. Besides how could carpet and furniture effect the temperature degree they need to be heated to to heat the house. I have 4 zones and all 4 zones could not get higher than 66-68 degrees.

I think I have answered most questions.

ChrisJ

Is there baseboard heat near or behind your bed?

Can the beds be located away from the heat?