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Will a 5" chimney liner work in this scenario?

jdanswers
jdanswers Member Posts: 8
Saw a closed thread that doesn't quite answer my question, so I'll try here. I replaced my old boiler with a Dunkirk hot water boiler WPSB-4D outputting 94,000 BTU. I have gradually noticeable condensation in the chimney since the install in Dec. 2007 causing interior ceiling damage. There are no leaks around the chimney. I had it pointed and resealed. 6 feet of the chimney runs through a cold attic and 3 feet is above the roofline outdoors. I am in Erie, PA where winter is pretty severe. Temps below freezing much of the time.
1. chimney height - 17' 6" top to bottom.
2. clay lined cement block chimney, straight, no bend. Inside dia 8"x7" sloppy mortar joints inside.
3. boiler has a 6" exhaust through a 5' up-angled run to chimney.
4. hot water tank also vents into the chimney, not sure of btu output. (Sorry)

I am considering an insulated flue liner but using a 6" won't fit the chimney as is. The 6" liner has an OD of 7.25. I could get away with a 6" liner not insulated but I am concerned about the extreme cold we have most of the winter.

A 5" insulated liner has an OD of 6.25 and likely would fit but will it give enough draft to expel gasses safely? My installer can't answer my concerns.

I turn to your expertise.
Thanks
JD

Comments

  • Robert O'Connor_12
    Robert O'Connor_12 Member Posts: 728
    edited April 2015
    I'd use a standard stainless 6" liner. When you put a liner in an existing tile lined chimney, you have (according to the tables) created a B Vent. You could break out the original tile liner to fit an insulated one which can be a fairly labor intensive to do. It's also possible you can go down one size, but be careful. This should be supported by your heating pro, applicable according to the B vent tables & be okay with the AHJ. In NJ you need a permit to install a liner and must submit supporting documentation & verification of chimney by heating pro when changing appliances.
  • vaporvac
    vaporvac Member Posts: 1,520
    I'm curious why you had the brick chimney sealed? Was it originally? On older houses this can cause problems as the brick is meant to breath and a sealant keeps all the moisture inside.
    Two-pipe Trane vaporvacuum system; 1466 edr
    Twinned, staged Slantfin TR50s piped into 4" header with Riello G400 burners; 240K lead, 200K lag Btus. Controlled by Taco Relay and Honeywell RTH6580WF
  • jdanswers
    jdanswers Member Posts: 8

    I'd use a standard stainless 6" liner. When you put a liner in an existing tile lined chimney, you have (according to the tables) created a B Vent. You could break out the original tile liner to fit an insulated one which can be a fairly labor intensive to do. It's also possible you can go down one size, but be careful. This should be supported by your heating pro, applicable according to the B vent tables & be okay with the AHJ. In NJ you need a permit to install a liner and must submit supporting documentation & verification of chimney by heating pro when changing appliances.

    Thanks for the response. I was hoping to not have to call a local HVAC person for advice since they could try to steer me into an expensive solution. I figured you guys would give me the straight story.
  • jdanswers
    jdanswers Member Posts: 8
    vaporvac said:

    I'm curious why you had the brick chimney sealed? Was it originally? On older houses this can cause problems as the brick is meant to breath and a sealant keeps all the moisture inside.

    I think you are responding to another query. My problem does not seem to fit your answer. (ex: no blocked chimney)
  • vaporvac
    vaporvac Member Posts: 1,520
    edited April 2015
    "I had it pointed and resealed. "

    This is what I was referring to, sealing the exterior of the brick, not sealing up the chimney.
    Two-pipe Trane vaporvacuum system; 1466 edr
    Twinned, staged Slantfin TR50s piped into 4" header with Riello G400 burners; 240K lead, 200K lag Btus. Controlled by Taco Relay and Honeywell RTH6580WF
  • jdanswers
    jdanswers Member Posts: 8
    vaporvac said:

    "I had it pointed and resealed. "

    This is what I was referring to, sealing the exterior of the brick, not sealing up the chimney.

    Sorry. I see. "Resealed" meant the chimney flashing not the bricks and mortar.

    Any advice about the flue liner size/type I should use?

    JD
  • icesailor
    icesailor Member Posts: 7,265
    "" A 5" insulated liner has an OD of 6.25 and likely would fit but will it give enough draft to expel gasses safely? My installer can't answer my concerns.

    I turn to your expertise.
    Thanks ""

    Your installer should have the knowledge and expertise to answer that question. Otherwise, IMO, he is no better than those that hand around HD looking for work.

    And if you have a gas boiler, the chimney needs to be lined, and the "installer" definitely needs to know how to calculate flue sizes and chimney sizing.

    Concrete Block chimney's with clay flue tiles are terrible. Most so called "Mason's" couldn't build a chicken coop out of bricks and not have it leak. The tiles are never set properly so they leak at the joints and the tiles crack.

    Any heating person that thinks that Power venting is a bad idea, has never built a chimney or laid bricks. Or finally figured out why all the brick chimneys they dealt with had such bad draft, and how you had such good consistent draft with a Power Venter.
  • ChrisJ
    ChrisJ Member Posts: 11,969
    edited April 2015
    I'm NOT a professional and as others have said this should really be handled by a professional in person that can see everything.

    From what I recall when I attempted to have my chimney lined the size of the liner goes by the height of the chimney and the boiler's input BTU rating. The manufacturer of the liner should have a chart that shows what the liner will handle under those conditions.

    For example from this website,
    http://www.chimney-liner-central.com/chimney-liner-size-guideline.html



    This chart should only be used as a rough idea as you should always follow what the manufacturer of the exact liner you are using says as well as local codes.








    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • jdanswers
    jdanswers Member Posts: 8
    "With all due respect, nobody on this site can possibly recommend that you utilize anything less than 6" because that size is the recommendation by the manufacturer of the boiler." Thanks for all your input. I guess I need to call a local HVAC company to look at my situation. I thought, by providing all the info here, I could get someone to calculate what liner could fit my situation. I have read elsewhere that there is some leeway in calculating liner size. Apparently those opinions are wrong.

    Thanks again, everyone.
    JD
  • ChrisJ
    ChrisJ Member Posts: 11,969
    jdanswers said:

    "With all due respect, nobody on this site can possibly recommend that you utilize anything less than 6" because that size is the recommendation by the manufacturer of the boiler." Thanks for all your input. I guess I need to call a local HVAC company to look at my situation. I thought, by providing all the info here, I could get someone to calculate what liner could fit my situation. I have read elsewhere that there is some leeway in calculating liner size. Apparently those opinions are wrong.

    Thanks again, everyone.
    JD

    Ahem...

    Did you read my reply? :)
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • jdanswers
    jdanswers Member Posts: 8
    ChrisJ said:

    jdanswers said:

    "With all due respect, nobody on this site can possibly recommend that you utilize anything less than 6" because that size is the recommendation by the manufacturer of the boiler." Thanks for all your input. I guess I need to call a local HVAC company to look at my situation. I thought, by providing all the info here, I could get someone to calculate what liner could fit my situation. I have read elsewhere that there is some leeway in calculating liner size. Apparently those opinions are wrong.

    Thanks again, everyone.
    JD

    Ahem...

    Did you read my reply? :)
    I did read it and it made no sense because I'm an idiot when it comes to tech jargon. My boiler is a Dunkirk hot water system. But, hey, thanks for responding. I appreciate your effort to help.

    JD
  • ChrisJ
    ChrisJ Member Posts: 11,969
    edited April 2015
    jdanswers said:

    ChrisJ said:

    jdanswers said:

    "With all due respect, nobody on this site can possibly recommend that you utilize anything less than 6" because that size is the recommendation by the manufacturer of the boiler." Thanks for all your input. I guess I need to call a local HVAC company to look at my situation. I thought, by providing all the info here, I could get someone to calculate what liner could fit my situation. I have read elsewhere that there is some leeway in calculating liner size. Apparently those opinions are wrong.

    Thanks again, everyone.
    JD

    Ahem...

    Did you read my reply? :)
    I did read it and it made no sense because I'm an idiot when it comes to tech jargon. My boiler is a Dunkirk hot water system. But, hey, thanks for responding. I appreciate your effort to help.

    JD
    Na, that doesn't make you an idot.
    All you need is to know the input btu of the boiler, which is on the tag on the boiler. If you give us the model we can help look it up.

    You then take that, and look at the chart and wherever the size liner you want intersects with how high your chimney is is the largest boiler that liner can support.


    You said a 5" liner at 17 feet so the closest thing is 15 feet. That gives you a maximum INPUT btu of 119,200.

    Chances are, your boiler will work with that, but we need to know the actual input btu of the appliance.

    But as was said, this all must meet local code as well.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • todd_ecr
    todd_ecr Member Posts: 91
    Per the NFGC, it is permissible to reduce the vent size 1 pipe diameter. You must carry the boiler's 6" vent all the way to the chimney connection(do not reduce it right at the boiler's vent damper.)
    The WPSB-4D' s input is 112,500. As others have mentioned, you must remain within the capacity of the liner. Add the water heater's input to the boiler's. If this total is not less than the maximum capacity of the liner for a given height and diameter, then it is not permissible.
    ChrisJ
  • ChrisJ
    ChrisJ Member Posts: 11,969
    todd_ecr said:

    Per the NFGC, it is permissible to reduce the vent size 1 pipe diameter. You must carry the boiler's 6" vent all the way to the chimney connection(do not reduce it right at the boiler's vent damper.)
    The WPSB-4D' s input is 112,500. As others have mentioned, you must remain within the capacity of the liner. Add the water heater's input to the boiler's. If this total is not less than the maximum capacity of the liner for a given height and diameter, then it is not permissible.

    I missed the comment about the water heater.
    Thanks for catching that.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    todd_ecr
  • RobG
    RobG Member Posts: 1,850
    You could also replace the water heater with an indirect tank to exclude it from the BTU factor.
  • jdanswers
    jdanswers Member Posts: 8
    todd_ecr said:

    Per the NFGC, it is permissible to reduce the vent size 1 pipe diameter. You must carry the boiler's 6" vent all the way to the chimney connection(do not reduce it right at the boiler's vent damper.)
    The WPSB-4D' s input is 112,500. As others have mentioned, you must remain within the capacity of the liner. Add the water heater's input to the boiler's. If this total is not less than the maximum capacity of the liner for a given height and diameter, then it is not permissible.

    Excellent! Thanks for taking the effort to give me this info. Yes, boiler is 112,500. The water heater is 35,500 (40 gal). This is 148,100 total. So, I need a liner that can vent this input based on length of liner and proper sized diameter. The length needed would be a minimum of 17.5 feet. It's still the diameter to be determined taking into account the clay lined chimney is 8"x7" inside dimensions with some sloppy mortar joints. The house is 60 years old.
  • RobG
    RobG Member Posts: 1,850
    Once again, if you abandon the water heater and use an Indirect you should be able to get by with a 5" liner. (I am just going by the specs above).
    Bob Bona_4
  • Robert O'Connor_12
    Robert O'Connor_12 Member Posts: 728
    If you use a 6" liner, and without knowing the connector rise so I'll assume (with Odd Couple Theme in my head) it's 1 feet (R)
    Now, using table G2428.3(2) {two or more Cat 1 appliances with single wall metal connectors}
    without interpolating height and use 15' (on the table)
    You get 116,000 btu's.
    Now, reduce it by 20% based on G2428.3.15
    or
    92,800. This is max based on code when using a liner.
  • ChrisJ
    ChrisJ Member Posts: 11,969
    This is actually the reason I ended up with a power vent heater.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • icesailor
    icesailor Member Posts: 7,265
    Its the input of the appliances, the length of the flue and the size.

    Being too big and too short is as bad as being too small a flue and too long. Everyone is different. Today, you have to calculate it.

    Its all in the NFPA codes to look up. The whole intent is to get the flue hot, and the gasses pass at an acceptable rate. 100 MPH isn't acceptable, nor is 1" per hour.

    You have to calculate it. Its on the gas code books and in the oil codes.

    Replacements are a whole other issue. They must meet standards too.

    I don't make the rules. I just had to work by them.
  • j a_2
    j a_2 Member Posts: 1,796
    It will work if the local code says it will..Bigger or smaller is equally as bad..
    icesailor
  • Mikey Lasagna
    Mikey Lasagna Member Posts: 10
    vaporvac said:

    I'm curious why you had the brick chimney sealed? Was it originally? On older houses this can cause problems as the brick is meant to breath and a sealant keeps all the moisture inside.

    Maybe true with older brick not true with newer brick or new wall systems eg: cavity walls

    The engineers would rather have the wall sealed and have weep holes to drain any condensation.
  • Mikey Lasagna
    Mikey Lasagna Member Posts: 10
    icesailor said:

    "" A 5" insulated liner .

    Concrete Block chimney's with clay flue tiles are terrible. Most so called "Mason's" couldn't build a chicken coop out
    of bricks and not have it leak. The tiles are never set properly so they leak at the joints and the tiles crack.

    Any heating person that thinks that Power venting is a bad idea, has never built a chimney or laid bricks. Or finally figured out why all the brick chimneys they dealt with had such bad draft, and how you had such good consistent draft with a Power Venter.

    I think you left out the hack chimney liner company's that "repoint" your chimney and repair the wash on top. I can't tell you how many times I'm called to a house to repair what did.




  • jdanswers
    jdanswers Member Posts: 8
    I want to thank everyone for advising me. I got three estimates from local pro's after discussing the finer points many of you made and those I learned in my online research. I have chosen one to do the work. I'll let you know if I chose wisely.

    Thanks again!
    JD
  • icesailor
    icesailor Member Posts: 7,265
    @Mickey Lasagna:

    And someone thinks that THAT is better than a Power Vent?

    Not in MY experience.

    Out of sight. Out of mind.
  • ChrisJ
    ChrisJ Member Posts: 11,969
    edited May 2015
    j a said:

    It will work if the local code says it will..Bigger or smaller is equally as bad..

    If local code says it will work but the liner manufacturer says it will not, what happens?

    I ask, because I always hear local code out ranks everything else.
    icesailor said:

    @Mickey Lasagna:

    And someone thinks that THAT is better than a Power Vent?

    Not in MY experience.

    Out of sight. Out of mind.

    In my opinion a B-vent is better than a power vent.
    No moving parts, no noise.

    I installed a power vent Bradford White 50 gallon water heater. Part of me wishes I didn't, part of me likes it.

    The part of me that wishes I didn't is the part that gets annoyed by the sound, annoyed by not having a water heater when the power is out, and the part of me that knows sooner or later I'm going to have to replace that expensive beast. Expensive when compared to an atmospheric vent heater and yeah, it's more efficient but there is no way it will ever pay for the price difference.

    Other than that, the noisy isn't that bad and it really seems like a good heater. It's just there are some cons to them.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • icesailor
    icesailor Member Posts: 7,265
    After April 1, 2015, you don't have a choice on larger sized gas water heaters.

    Buy an unsold grandfathered one and save it until you need it.
  • ChrisJ
    ChrisJ Member Posts: 11,969
    icesailor said:

    After April 1, 2015, you don't have a choice on larger sized gas water heaters.

    Buy an unsold grandfathered one and save it until you need it.

    Is that in MA or all of the US?
    What is "larger" ?

    Na, I don't dislike it enough to hoard one.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • vaporvac
    vaporvac Member Posts: 1,520
    I think it's over 50gal? I bought my Rheem atmospheric recently and it's so quiet and much more efficient than the old one due mainly to insulation and the piping. We have outages here all the time; having no heat is bad enough, I'd be sunk with no hot water.
    Two-pipe Trane vaporvacuum system; 1466 edr
    Twinned, staged Slantfin TR50s piped into 4" header with Riello G400 burners; 240K lead, 200K lag Btus. Controlled by Taco Relay and Honeywell RTH6580WF
  • icesailor
    icesailor Member Posts: 7,265
    edited May 2015
    ChrisJ said:

    icesailor said:

    After April 1, 2015, you don't have a choice on larger sized gas water heaters.

    Buy an unsold grandfathered one and save it until you need it.

    Is that in MA or all of the US?
    What is "larger" ?

    Na, I don't dislike it enough to hoard one.
    FEDERAL.

    Nothing to do with Massachusetts other than Massachusetts is covered along with every other jurisdiction in the USA,

    "Larger" means it has a larger diameter and height for additional insulation.

  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    edited May 2015
    New DOE mandates. Is going to be a real problem for installs that are tight already. Condos, etc.
  • SWEI
    SWEI Member Posts: 7,356
    edited May 2015
    Straight from the CFR:


    How long 'till we see the first 55 gallon model?
  • j a_2
    j a_2 Member Posts: 1,796
    ChrisJ said:

    j a said:

    It will work if the local code says it will..Bigger or smaller is equally as bad..

    If local code says it will work but the liner manufacturer says it will not, what happens?

    I ask, because I always hear local code out ranks everything else.
    icesailor said:

    @Mickey Lasagna:

    And someone thinks that THAT is better than a Power Vent?

    Not in MY experience.

    Out of sight. Out of mind.

    In my opinion a B-vent is better than a power vent.
    No moving parts, no noise.

    I installed a power vent Bradford White 50 gallon water heater. Part of me wishes I didn't, part of me likes it.

    The part of me that wishes I didn't is the part that gets annoyed by the sound, annoyed by not having a water heater when the power is out, and the part of me that knows sooner or later I'm going to have to replace that expensive beast. Expensive when compared to an atmospheric vent heater and yeah, it's more efficient but there is no way it will ever pay for the price difference. Chris, the local code,defers back to the manufacture installation instructions…Any and all appliances/fixtures must be board approved…Anyway thats how it is here in Mass...

    Other than that, the noisy isn't that bad and it really seems like a good heater. It's just there are some cons to them.