Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

How to tell if old flue is asbestos?

ThinkpadUser7
ThinkpadUser7 Member Posts: 137
edited January 31 in Chimneys & Flues
This is the flue that connects to my hot water heater and boiler for the radiant heating. The house was built in 1947. I'm currently pursuing having all the equipment in this closet replaced but I'm not sure how to tell if the flue is asbsetos or just an "old vent that’s made of high temp. light weight concrete" as one person called it. I don't really want to touch it. Short of hiring someone to test it, is there any way to tell?

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 24,839
    It may well contain asbestos. Only way to be sure is to have it tested by a certified person.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Bob Harper
    Bob Harper Member Posts: 1,089
    Transite cement/ asbestos. Was approved back in the day. Should be replaced with modern type B-vent or convert appliances to power vent but still remove. Agree w/ Jamie have it tested. If positive, contract with certified asbestos abatement contractor to do it right so there is no impediment on the title of the property or that anyone is huffing it. Worst thing you can do to asbestos is disturb it. If you must disturb it, be trained, qualified and equipped to do it.
  • pecmsg
    pecmsg Member Posts: 5,290
    The only way to know is to have it tested by a certified lab. 

  • bburd
    bburd Member Posts: 1,039
    The heat resistant paper wired onto the vent pipe at the bottom of the photo also probably contains asbestos.

    Bburd
  • mattmia2
    mattmia2 Member Posts: 10,920
    edited January 31
    I think the only "high temp light weight concrete" is asbestos cement, also known as Transite as stated above.

    That looks like asbestos paper or aircell around that other vent as well unless it is a transite pipe in to a steel ell.

    In any case it should be tested but I think everyone here would be shocked if any of it isn't asbestos.
  • Big Ed_4
    Big Ed_4 Member Posts: 3,019
    Wow , I never seen that type of vent . What part of the Country was that system used ?

    There was an error rendering this rich post.

  • ThinkpadUser7
    ThinkpadUser7 Member Posts: 137
    Big Ed_4 said:

    Wow , I never seen that type of vent . What part of the Country was that system used ?

    This is in the S.F. Bay Area
  • ThinkpadUser7
    ThinkpadUser7 Member Posts: 137
    About half the people that have come out to give me bids on replacing the equipment/flue has mentioned the asbestos concern and the other half have made no mention of it. It's kind of surprising to me that so many don't know or care. These are all reputable radiant heating companies.
  • Big Ed_4
    Big Ed_4 Member Posts: 3,019
    edited February 1
    I am thinking it looks small in size , maybe originally vent for a Kelly Pot which is an oil dripper . What fuel do you have access to ?

    There was an error rendering this rich post.

  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,518
    Looks like Asbestos-Cement pipe. ONLY way to know is lab test with Electron Microscope.  Assume it is...Mad Dog 🐕 
  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,518
    The good thing about AC is that its not usually Friable, so removal is very quick and easy. Mad Dog 🐕 
  • ThinkpadUser7
    ThinkpadUser7 Member Posts: 137
    Big Ed_4 said:

    I am thinking it looks small in size , maybe originally vent for a Kelly Pot which is an oil dripper . What fuel do you have access to ?

    Natural gas. You can see the boiler here, which is likely original to when the house was built:

  • Big Ed_4
    Big Ed_4 Member Posts: 3,019
    Yep , Look into a wall hung Combe . Do you have a good outside wall or do you have to send the vent up through the old ?

    There was an error rendering this rich post.

  • mattmia2
    mattmia2 Member Posts: 10,920
    edited February 1
    is that a 120v gas valve? was the baso switch a retrofit?

    did someone pull out the boiler and put it back to replace the water heater? you want to fix that with the new install.
  • ThinkpadUser7
    ThinkpadUser7 Member Posts: 137
    Big Ed_4 said:

    Yep , Look into a wall hung Combe . Do you have a good outside wall or do you have to send the vent up through the old ?

    Yeah, I'm looking into a combi boiler given the space constraints and minimal domestic hot water needs. It would be awkward to try to route the vent somewhere other than through the existing roof vent.
  • ThinkpadUser7
    ThinkpadUser7 Member Posts: 137
    edited February 1
    mattmia2 said:

    is that a 120v gas valve? was the baso switch a retrofit?

    did someone pull out the boiler and put it back to replace the water heater? you want to fix that with the new install.

    I'm not sure about the 120v gas valve and also not sure if that baso switch was original.

    I had to replace the water heater heater about 15 years ago and the boiler needed to come out to do it. I also had a gas leak behind the water heater about 8 years ago that required both the boiler and water heater to come out. My plan was to replace everything in the closet with a combi boiler so that all parts will be easily serviceable going forward.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,378

    How to tell if old flue is asbestos?

    I'm thinking a taste test is out of the question.

    In California... I remember doing some taste testing a few years back.

    But that may have been at a Winery

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?