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Odors and headaches. Help!

Hi! We bought a house last spring that has a woodstove and a forced hot water boiler with baseboards. Over the summer we had the boiler serviced and were told there was a clog and got some terrible odors in the basement when the flushed it, but assumed that it was all
set after that. We think the previously owner used the woodstove as the primary heat source so probably didn't use the heat much. Over the first few weeks we started getting terrible odors in the house, mostly at night and after lots of investigating, ended up having to re-do all the plumbing in the house due to open vent pipes in the walls and faulty plumbing in the walls done by the previous owner. We assumed the odors would resolve after that, at that point knowing we had had septic gasses constantly venting into the walls. We moved back in and started getting headaches and odors again. Not the same odor as the septic gasses, but similar to  the odor from the flushing of the boiler from the summer. It was strongest coming from one of the baseboards in the living room. The plumber came back and discovered a carbon monoxide leak in the old boiler, which also had some other issues, so we ended up replacing that with a navien high efficiency boiler. We assumed that that was the cause of the headaches and perhaps the smell
was just residual from the septic issues and would just take time to dissipate. Since the boiler has been replaced and the carbon monoxide leak is taken care of, as well as all of the septic issues, we are still getting an odor (similar to the one when the old boiler had a clog over the summer) and severe headaches and nausea, which is the worst in the living room. We had an air quality test done which told us we had very high carbon dioxide levels in the hosue as well as high levels of VOC’s concentrated around that same radiator in the living room. Directly underneath that radiator in the basement was a bunch of old insulation which we removed thinking perhaps that was the source of the vocs but even after removing that we are still
getting odors and headaches and were told by the air quality specialist not to sleep In the house until we lowered the vocs and carbon dioxide levels. We just don’t know what to do next? It’s a closed system so not sure how the water inside could be smelling on the outside or be causing high VOC levels? I hope this makes sense? We have essentially been sleeping on the porch since September. Any ideas greatly appreciated! 


  • Ironman
    Ironman Member Posts: 7,119
    Do you have a gas water heater?

    How about some pics of the boiler and any other fuel burning appliances?
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • neilc
    neilc Member Posts: 2,196
    the Navien is direct vented to outdoors, correct?
    it's fresh air also, correct?

    Is there a separate domestic hot water heater?
    Post a picture of both,

    what's above and below the livingroom?

    sounds like a pipe is still open there somewheres,
    are you sure you fixed them all?
    known to beat dead horses
  • megr
    megr Member Posts: 2
    Thanks both so much. It is direct vented outside but the air intake is in the basement. It is gas and it heats the hot water there is not a separate hot water tank. Below the radiator is the front wall of the house which has the electrical panel on it and a little ledge that had a bunch of hold insulation on it which we removed and cleaned. The house is balloon framed. Above it is our bedroom. We have a cast iron grate in the ceiling directly above the radiator where the heat from the woodstove is meant to go up to the bedroom. So I think the smell is moving up that way. 
  • megr
    megr Member Posts: 2
    We ripped out the entire kitchen and bathroom so every bit of plumbing in the house and entire vent was redone. 
  • pecmsg
    pecmsg Member Posts: 3,879
    1st Carbon Dioxide or Carbon Monoxide?

    W A G sewage spill in the walls?

    Look into a ERV or HRV bringing in fresh air and exhausting stale air. Try and maintain slight Positive pressure in the envelop forcing odors out.

    Compliments to the installing contractor
    Very neat install
  • Ironman
    Ironman Member Posts: 7,119
    Have the air intake run outside with the exhaust. The way it now is it's putting the house in a negative pressure which can cause odors to be drawn in.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • iced98lx
    iced98lx Member Posts: 59
    Ironman said:

    Have the air intake run outside with the exhaust. The way it now is it's putting the house in a negative pressure which can cause odors to be drawn in.

    This, if you went around and did a bunch of air sealing and "tightened" the house up you could have blocked the paths where combustion air would normally infiltrate back into the house. You may un-intentionally now be pulling it from somewhere else, even somewhere that pulls some of the exhaust from your new boiler in.

    By piping the intake outside you will create a sealed combustion process, that basically nets the house zero change in air pressure or combustion gases (that's the goal, anyway). You'll also create a pipe that NEEDS to take in air to heat your house and water. If you're somehwere that gets a lot of snow/etc the plumber may have been trying to save a return call by not piping it outside and letting it get frozen/snowed in.

    An ERV/HRV as suggested will absolutely help lower C02 levels, but sometimes finding the root cause is easier, I dare suggest that based on the age of the house it's not well sealed enough to NEED an ERV/HRV most likely but that's 1000% speculation without a blower door test, perhaps you recently completed a deep energy retrofit we're not aware of :wink:

    Are you seeing any make up water going into the system now that it's stabalized? You've made sure that radiator in the living room isn't leaking I assume.
  • neilc
    neilc Member Posts: 2,196
    why the open earth under the boiler?
    any others?
    If you put your nose to that , , , does it stink?
    why the waste basket?
    seal a sheet of plastic to the slab and wall,

    post a picture of the vent sticking up thru the roof?
    I've had commercial jacks that were counter capped, and the vent stink was coming back down the jack boot,
    not likely with a residential boot, but ya never know,
    picture of that vent stack,

    any air conditioning?
    air handler trap dried out?

    clothes washer flood pan? or other floor drains?
    trap dried out and passing gas ?
    known to beat dead horses
  • mattmia2
    mattmia2 Member Posts: 7,736
    Broken sewer under the slab and leaking?

    What sort of odor is it? Is it metallic? Is it burning plastic? Is it some form of animal waste? Is it chlorine like bleach? Is it acid like vinegar or citrus?
  • Zman
    Zman Member Posts: 7,446
    I would have a contractor plug your plumbing vents and do a smoke test on your plumbing to eliminate the possibility of a concealed sewer vent issue.
    It would be better if the boiler was pulling combustion air from the outdoors. Right now the boiler is trying to pull combustion air from every nook and cranny.
    I assume you have CO alarms and you are positive that is not the issue?
    To the best of my knowledge, CO2 is high when there is not enough ventilation to exhaust the CO2 being put into the air from the living organisms in your home. Your house would need to be very tight or you would need to have a LOT of people living in your house for it to be coming from humans. I would suggest contacting a good independent industrial hygenist and have them perform some test cultures for mold. Do not, under any circumstances allow a mold abatement contractor into the house until you have had an independent test done. Mold abatement contractors have one goal, find mold and scare you into spending lots of money! A medical professional who deals with allergies may be able to refer you to a good hygenist.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
    Larry Weingarten
  • megr
    megr Member Posts: 2
    Very high carbon dioxide in the house. Small home. We also had a previous carbon monoxide leak in the previous boiler but that was resolved when we replaced. 

    No sewage in the walls just sewer gasses from the open vent pipe that was in the wall broken in several places.

    The open earth under the new boiler was from what was under the old boiler that was removed. We have some plastic to seal it. It does not smell.

    no air conditioning in the house. Currently vent pipe for sewer is on roof 2 ft about below the ridge. Vent for boiler is right out the window behind the boiler. Picture attached.

    We have done smoke and peppermint tests before and after re-do if plumbing. It is not sewer gas. We also had the air quality guy test for that as well after the plumbing work was done and kitchen and bathrooms redone. 

    The smell now is concentrated in the living room (which was not redone) where there are two small baseboards and a woodstove. The air quality guy said there is high carbon dioxide due to lack of good air flow in the house and the vocs were the highest on the front wall of the living room where one of the baseboards is and directly below that in the basement where there was previous insulation that we have since removed. I get a head hache about 15 min after being in there. That is also the location where I get the odor that I smelled when we had the old boiler serviced and he removed what he called a clog... it’s a musty/chemical smell. Hard to describe. Not like the sewer gas smell which to me smelt like a dead animal.

  • icy78
    icy78 Member Posts: 404
    Some questions.

    What is the C02 number they said was really high? Did you see the meter?
    Does the C02 number rise when the boiler is firing?
      Was ANY C0 measured?
    Did the IAQ guy actually have a meter that registered C0?

    [BTW, there wasnt  a carbon monoxide "leak"  found....it would be a flue gas "leak" and probably fixable with a venting and/or a combustion air fix.]

  • psb75
    psb75 Member Posts: 699
    How often and how much are you using the wood stove? That creates significant negative pressure inside the house when burning. Heated houses in the winter have net negative pressure generally. The boiler drawing inside combustion air, woodstove burning, bath fans, kitchen hood, all exacerbate the situation.
    High CO2 levels are 1.) buildup of created CO2 not being exhausted effectively and replaced by new O2 or 2.) an incursion of excess CO2 from an unknown source. A heat-recovering air changer could resolve the issues. You should have a blower door test to discern the "tightness" of the building AND to discover any unknown leakage areas.
    By the way, where is the condensate from the Navien going? Just curious. Is that what the waste basket is for? Are there any basement floor drains? If so are they trapped?
  • psb75
    psb75 Member Posts: 699
    I also forgot to mention that a clothes dryer-- electric or gas ALSO adds more negative pressure to the house when operating.
  • megr
    megr Member Posts: 2
    Thank you all. He did have a meter. I will have to look on the report for the Exact levels. It was a flue gas leak but there were several other issues as well and we wanted to upgrade the system eventually anyway. 

    Any ideas on where the smell and vocs could be coming from? 

    The negative pressure is a separate issue I think, but it does make sense to look into that more deeply. There is a gas dryer. We don’t use the woodstove much right now as we thought that was possibly the cause of smells and headaches. But they haven’t gone away since we stoped using it..... 

    There is no drain in basement floor. 
  • neilc
    neilc Member Posts: 2,196
    did the air quality guy do any mold testing ?
    can they?
    what kinds of furniture in that room?
    particle boards? foam cushion footons?
    and that boiler exhaust, wondering if exhaust is being sucked back in thru that fiberglass insulation,
    the fiberglass is NOT an air barrier, no matter how tight it may be packed,
    and what insulation was removed? and why? spray foam? any residual or missed in the walls or ??
    is the house well sealed otherwise?
    known to beat dead horses
  • megr
    megr Member Posts: 2
    Thanks again all. The fiberglass to the outside needs to be sealed. We just haven’t gotten to it yet but it is on the list! We are awaiting mold test results. 

    The fiberglass that was removed was what was insulating the basement ceiling and around the edges of the basement where the balloon framing was. There is other Insulation blown up into the walls but we have not been able to remove all of that. 

    Can anyone recommend a good air quality tester that I could
    purchase myself to monitor the vocs and co2 as we complete each step, so I can monitor of what we are doing is actually helping? I can’t afford to have the air quality guy come back and want to make sure it is safe before we move the kids back in. 
  • neilc
    neilc Member Posts: 2,196
    I think you need to find a better air qualities guy/gal that can help you pinpoint the sources,
    where are you located ?
    your monitoring doesn't make the issues go away,
    is the house so well sealed that the CO2 is just your and yours' exhalations?
    cook with gas ?
    gas fireplace(s)?
    you could buy CO2 monitoring at local HVAC supply,
    VOC's may be harder to find,
    Supply house . com ?
    known to beat dead horses
  • Jamie Hall
    Jamie Hall Member Posts: 21,111
    CO2 monitoring? Or CO? Same two letters, totally different compounds. One is quite normal. One is lethal. What are we talking about here?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • neilc
    neilc Member Posts: 2,196
    I am referring to CO2, carbon dioxide, the less deadly of the 2,
    OP says the CO issue had been dealt with,
    but that there is still high levels of CO2,
    and VOCs,

    I am still questioning molds,
    and their abilities to make CO2 and VOC as byproduct,
    is there a resident IAQ specialist here?
    known to beat dead horses
  • megr
    megr Member Posts: 2
    Yes not carbon monoxide. We have high levels of carbon dioxide and vocs. IAQ specialist said the vocs were highest in the front wall of the living room, which is the front wall of the house and directly above that in our bedroom and below in the basement. We are still waiting on mold test to Come back. I just want the monitor to know if levels are going down as we try different things to identify the source. For example, removing the insulation.
  • dcbraley
    dcbraley Member Posts: 15
    Have you checked if the house ever had an underground oil tank? possibly leaked into the soil? The house is old and probably had oil heat before gas. With what looks like a rubble foundation and balloon framing the voc's could probably easily enter the house.
  • Jamie Hall
    Jamie Hall Member Posts: 21,111
    May I ask what kind of insulation is present, and when it was installed? The combination of odours, high C)2 and high VOCs sounds a lot to me like off-gassing from some types of foam in place insulation. And this of-gassing, for some types, can go on for months or even years.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • megr
    megr Member Posts: 2
    I have not checked about the underground oil tank but will see what I can find out. Most of the insulation that was present in the basement was a mix of fiberglass and mineral wool. There was cellulose blown into the walls at some point. 

    We just bought the house in 2020 so I’m not sure exactly when those things were done. I know that when we ripped out the walls to fix the septic venting issues we put in mineral wool around the ballon framing. And I think fiberglass in the walls? 

    I know the front porch was re-done in 2004 which is right up against the wall that had the highest concentration of the VOCs. There wasn’t much in terms of permits from previous owner so hard to track when they did what...