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Discuss Radiator emitting strong odor when heat goes up in the Central Heating Forum area at

  1. John93

    John93 Member

    Greetings everyone,

    I live in a small building. My unit has 1 bedroom. The bedroom radiator has been inoperable for over 10 years. The living room rad has operated just fine in that time. It is a cast iron base board radiator powered by hot water. Not steam.

    This past summer a plumber was dispatched and he was able to turn on the bedroom radiator. This fixed the issue regarding not having heat. In the fall it began to radiate heat. There was no smell at that time. Very briefly for one day or so a faint smell was there. But it went away immediately.

    Since the real cold began in December. The bedroom radiator emits a very strong odor. I contacted the plumber who got the rad working. He advised me to use compressed air. Or to let it burn through whatever had accumulated for 10 years of not functioning.

    After 4 weeks. Where the smell did not get any less intense. I used a compressor and blew out that radiator. When I started forcing air through it. Silver foil and also black backing paper which was situated behind the silver foil started to come out. I also forced 2 large clouds of dust out on both ends of the rad.

    After that one session. The smell became somewhat less in concentration. I decided to blow out the rest of the silver foil and black backing paper. This also reduced the concentration. I then scraped the bits left near the top.

    So at that point looking into it visually. It is just wood back there. With some small spaces between the wood where drywall is seen. Other than that it is essentially empty.

    The smell is greatly reduced. But is still off gassing something as it is not a clean smell in the bedroom.

    I have spoken to a few people on this issue. Which made me think to turn to the forums to get some kind of help. As this matter is now ongoing and I have no way of isolating what the smell could be.

    People have asked me if there are any leaks. Either from the rad or bleeder valve. I can confirm that there is no leak whatsoever. There is carpet in both the bedroom and living room area. The carpet is not too dark. So any leak, especially that black water running through the heating system in our small building would show up on the carpet. I also left paper around the pipes to see if anything leaked and it was dry.

    The smell disappears when the heat is off. So it cannot be mold.

    The very frustrating thing about this scenario is that the materials in both the bedroom and living room are identical. Both radiators were painted with the same oil based paint. Both living room and bedroom have the same carpet. The living room radiator does not emit any kind of smell whatsoever. And yet if I look inside with a flash light it has that silver foil and black backing paper. But does not smell at all.

    Which brings me to the very heart of this problem. If both rooms have the same materials surrounding the radiators. And seem to be painted the same. Likely installed by the same people at the same time as radiators are identical. Meaning one is not any newer in terms of model or make.

    For some unknown reason the bedroom radiator emits a strong odor when the heat goes up. It is much less now that I used the air compressor. But not enough to breathe it in. I do not know exactly what is in the air but it does not smell to me to be safe to inhale for prolonged periods of time.

    I have had contact with one person from another site. He keeps saying there must be a chemical or pesticide used on the bedroom rad. That does not seem likely. Pesticide was not used. As for chemicals. That I am not certain about. Both rads look the same to me and have the same surrounding materials.

    Now the bedroom rad has no silver foil or black backing paper inside. And I am trying to isolate what that smell could be. And then take some kind of action to lessen it. But I cannot understand what is heating up and emitting that smell?

    Cannot be mold. Otherwise smell would not disappear with the heat off. Is not a leak, as that would show. Also a leak would smell even with the heat off. Carpet goes underneath the rad. But carpet is in the living room as well and no smell at all there.

    Can wood or dry wall cause this sort of smell when heated?

    How does a person go about isolating a smell? I cannot think of a logical way to approach this problem. I forced air through that rad thinking it would improve the smell. And it worked to reduce the concentration of the smell. But did not get rid of it. It is much less now but even at let's say 7% concentration, that room is not likely safe to sleep in.

    Hence my turning to the forums in the hopes that someone with experience could point me in the right direction. As I have researched this endlessly. And am no closer to finding a solution.

    Any feedback or assistance would be immensely appreciated. Thank you.
  2. jtsplumbing

    jtsplumbing Plumber GSR

    Dead rodent,
    • Useful Useful x 1
  3. John93

    John93 Member

    This is possible as there was a mouse that would come out of that rad from time to time.

    If it is a dead rodent. What does one do to get rid of that smell?

    Also, this smell has been here since December. Can a small mouse release this much smell under so much heat?

    Wouldn't the intensity of heat burn through the mouse remains relatively quickly? Could one mouse cause a smell that has not abated in over 2 months?
  4. jtsplumbing

    jtsplumbing Plumber GSR

    Simple answer is yes they stink, you need to find the corpse may be more than one. In fact there is always more than one !!
    • Useful Useful x 1
  5. John93

    John93 Member

    The bedroom radiator has 2 pipes that come out of the floor. The right side of this radiator is where the mouse would come out from. But when I open the panel on both sides of the radiator. It is just solid concrete with holes for the pipes. How can I get down there to remove the dead rodents? There is a floor directly below me.

    When I had the compressor I thought about blowing air into the holes around the pipes. But my concern was that I would move things and the smell would go to the living room which is the only room I can sleep in. I am currently living out of that living room. Have been for the last 2 months. Cannot sleep in the bedroom due to that smell.

    How can I get to the dead mice/mouse if it is solid concrete and only small circle openings around the pipes? I guess I could blow compressed air the other direction. Away from the living room, and away from the bedroom. But without a place for it to leave or vent would I accomplish anything by blowing compressed air into the space beneath my floor? And secondly, would there not be a chance that I could blow the debris into the space below my living room rad and then that would be releasing a smell?

    What can a person do, if it is solid concrete and no way to get to the mouse/mice? Is there something which can speed up the decomposition process?

    Would calling a pro help with this kind of thing? And if so, would it be a pest control type of service or a heating/plumber?

    I guess in theory if the pest control people have a camera that can look into holes. They would confirm whether there are mice or a mouse there. But how would they remove the dead mice/mouse? This would require a very thing type of vacuum or some other tool designed to pull from very small crevices and spaces.

    Do such tools exist?

    Can a dead mouse or mice smell for over 2 months? Last question. Is the smell from a dead mouse harmful to breathe? Meaning can I keep the door and the window open and sleep in that room until I look into pest control?

    By the way, a massive thank you to jtsplumbing. So far you are the only person who has come up with something which is even remotely close to explaining the cause of this smell.
  6. John93

    John93 Member

    I would like to point something out as this may be relevant.

    The smell which the bedroom radiator is releasing does not smell like something dead and rotting. It has more of a chemical smell to it.

    Also, when I had the 2 end caps off, which exposed the pipes coming up and down through the floor below. I would try to smell where the scent was coming from and it was from the radiator. Not from the end points at the left and right sides where the pipes come up.

    If the rodents were dead and being cooked. It would make sense that the smell would come up from the sides where the concrete opening are for the pipes that lead into the rad. But those openings did not smell. They produced no scent at all.

    Only the radiator has a smell. Meaning the port holes at the top of the cast iron base board rad had the scent. No way the mouse died in the rad as it is too narrow for the mouse to walk in there. It is like a grill on the inside.

    Can someone confirm or relay what a dead mouse smells like? Can this smell be similar to a chemical smell? Like burning paint? Or oil based paint that is off gassing?

    Or is the smell of dead rodents very different from that?

    Who would I contact in order to get this removed?

    A friend recommended that I contact the city inspector/fire department as they have tools to measure the air quality and identify the source of the smell.

    Thank you.
  7. Gasmk1

    Gasmk1 GSR

    i dont think it is a dead rat, found this on a search "Unfortunately it may take three weeks or more to completely decompose. A professional may be contacted to break through and rebuild affected walls. This can be costly and not a viable option. Even after elimination of the source of dead rodent smell, the unsettling scent may linger for up to two weeks".
    dont know if heating up would make a difference. i presume you are in USA, is it baseboard radiators, if so doesnt the cover lift of.
    may be worth getting the plumber back.
    • Useful Useful x 1
  8. John93

    John93 Member

    Hi Gasmk1,

    I think what you found makes perfect sense. As this burning smell has been here for almost 2 month now. Which would put it well past the timeline stated in the article. 3 weeks to decompose. Another 2 for the scent to leave. That's 5 weeks. This is now at around 7-8 weeks.

    I am curious about what the fire department or city inspector can do to diagnose the smell. If it is oil based paint that is off gassing. As that is one possibility. The rad may have been painted by the previous owner and left off. Meaning it never cured. The bedroom rad has been inoperable for over 10 years. This could be related.

    Again the smell is not of something dead or decomposing. But like a burning chemical or fume. Hard to describe the smell. It is not damp. It does not smell rotten. It smells like a burning smell of some kind. Not plastic. More like a paint of fume, or even like materials inside the rad are heating up and off gassing. But all that is left inside is wood. As I wrote earlier after I used the air compressor, I blew out all the silver foil and black backing paper. So it is just wood and a bit of dry wall and some metal brackets inside.

    I will include some pics.

    2018-01-31 11.49.30.jpg

    2018-01-31 11.50.10.jpg

    2018-01-31 11.50.41.jpg

    2018-01-31 10.29.16.jpg
  9. John93

    John93 Member

    Pic 1 shows the sides where the pipe and bleeder valve are.

    I put foil there, to block the mouse from coming in. The smell began before I put the tin foil around the pipes in the side brackets where the concrete holes are.

    I imagine that if the smell was due to dead rodents, the smell would come up from the sides of the rad where the pipes come in. But that is not where the smell comes from but instead from the entire span of the rad.

    There was no smell at all at the sides where the pipes come in.

    The port holes I mentioned run along the top of the rad. That is where I smell this fume.

    The last pic is a close up of the black backing paper that was directly behind the silver foil which lined the entire inside of the radiator. When I used compressed air. I blew out all of this material. For some reason I thought this could be causing the smell. And the intensity of the smell did drop significantly after all of this material came out. But did not disappear completely. Which is why I am still trying to figure out how to resolve this and get my bedroom back.

    Sleeping and living out of my living room close to 7-8 weeks now. This has not been what I would categorize as enjoyable.

    The great line "Winter of our discontent" certainly springs to mind. :)
  10. jtsplumbing

    jtsplumbing Plumber GSR

    Can you remove the entire panel for the length of the heater you will be amazed where rodents can get.
    • Agree Agree x 1
  11. gmartine

    gmartine GSR

    Yep, you need to get in there somehow or call the landlord (if renting) for rodents and smell. Incidentally I guess you're not writing to us from the UK, perhaps a forum nearer to home will be more familiar with this type of installation.

    It might be possible to clean/dislodge behind the panel by rodding with the right equipment if there is room (flue cleaning kit).
    Last edited: Feb 3, 2018
  12. John93

    John93 Member

    jtsplumbing, I don't doubt that the mouse can get in there. There's just nothing there to eat or attract them. They were coming up that pipe and through the opening around it. Then into my living room, and then most likely the kitchen.

    I wish I could take it apart but I live in a building and it would mean draining the entire system and having a plumber rip it out of the wall and then get a dry wall guy to fix it up.

    One other person mentioned a heat gun. To increase the temperature significantly.

    I wonder if this could help to speed up the off gassing?

    jtsplumbing, can you confirm what does a dead mouse or mice smell like? Can they smell like burning paint or chemical? Or does it smell rotten like rotten flesh?
  13. gmartine

    gmartine GSR

    • Like Like x 1
  14. jtsplumbing

    jtsplumbing Plumber GSR

    John you need to get that panel off asap just because they were running across the floor doesn't mean they were just coming up through floor, on a site seeing trip they are after food, to feed young, could be hundreds of them, Please nothing to attract them ! they may be nesting in there after all its nice and warm
    • Like Like x 1
  15. John93

    John93 Member

    JTSI hear what you are saying. Will have to talk to my building to see what can be done about getting that panel off. If they were nesting in the radiator grill, who knows what is in there.

    You seem to be very experienced with this sort of thing. In the times that you have come across something like this, what do burned rodents smell like? Do they smell like burned paint? Or is the odor more like dead flesh or something rotting?

    I have no point of references to gauge the scent or make any kind of comparison.
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