Switching from oil to gas: Do i need to change the chimney liner?


Old 01-15-14, 06:44 AM
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Switching from oil to gas: Do i need to change the chimney liner?

Hello everyone,

I just moved into a 100 year old home and had someone come in to do a chimney sweep so I can start using my fireplace. In my home, fireplace is on the main floor, below in basement is boiler and hot water heater, which all share the same chimney. The boiler was converted by the previous owner from oil to gas in December 2012. The boiler is 26 years old.

Of course, once the guy took a look at our current situation, he said our interior tiles were deteriorating, we had a CO2 risk and that we had $2k in repairs to fix the flue liner for our boiler and $3k for the chimney. He did not go on my roof or stick a camera down my chimney to do a full inspection (his estimate is attached as "company name removed by Mod"). I've also since then purchased additional CO2 detectors and placed throughout the home and all say I have a 0 level of CO2 currently.

Since that time, I've had 3 supposedly reputable chimney companies come in and assess my situation. Two did not put a camera down my chimney and estimated just over $3k total in repairs to install a new liner, top mount, and repair to the ashpit/firebox for the fireplace (they did not believe that I needed a new liner for the fireplace). One the estimates is attached under "Company name removed by Mod".

Problem now is the 4th one to come in actually stuck a camera down and this is what he is saying:

This two flue chimney was constructed without a wythe (separation between flues in
the system). This creates certain challenges to repair and restoration of the
chimney. Removal of the terra cotta liner tiles from the fireplace will directly affect
the terra cotta liner tiles from the heating appliance flue.

ISSUES: Damage found to flue liner, mortar joints and smoke chamber due to age,
use and water/moisture exposure.
Scaffold set up and break down
Remove firebox and old damper frame
Break out and remove terra cotta liner tiles from fireplace flue. This will result in
breaking of portions of the heating appliance flue
Install 7 x 11 stainless steel lining system for the fireplace from Forever Flex with
lifetime manufacturers warranty
Insulate the liner as required by manufacturer with ceramic blanket insulation
Re-engineer smoke chamber with UL listed Chambertech 2000
Install top sealing damper
Construct new firebox, adding poured insulation behind for efficiency and safety
Material and Labor expected costs: $7,239.00

ISSUE: Damage to the clay flue liner tiles
Install 8" ovalized liner system from Forever Flex to accommodate current
Install custom UL listed stainless steel base tee with separate entrances for each
Install UL listed support and top plate
Make connections to appliances
Material and Labor $ 3,214.00

ISSUE: Poor methods of past repairs, tarred crown wash, damaged mortar joints,
silicones mortar joints, tarred flashing. This proposal will address the masonry
issues but you will need to consult with a professional roofer regarding the flashing
and cricket needs.
Remove tar from crown wash.
Power wash chimney to remove moss and algae
Grind out mortar joints from roof up
Apply mortar to stone joints (tuck point)
Apply new crown wash.
Install multi flue stainless steel chimney cap to cover both flues
Material and Labor: $2,900.00


I'm trying to see if anyone knows the following:

1. Is this last estimate inline with what costs normally would be for this type of work or are they adding a lot of additional unneeded items? If they hadn't stuck the camera down, I'd figure this was all BS but considering he's the only one that did, not sure if the others came in lower knowing they would upcharge once work began.
2. Currently we do not have central air in the house and the boiler is old. If I were to convert to forced air and heat, how much of this chimney work do you all think would actually need to get done so I can just use my fireplace? If this last quote at $13,500 is accurate, I can put in a new system with central air for not much more than that...

Thanks for you help!!

Last edited by Gunguy45; 01-15-14 at 07:22 AM. Reason: Removed pics with company names showing. Don't think they were really needed.
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Old 01-15-14, 06:47 AM
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Moved to own thread...

Hello and welcome...

Someone will answer shortly... Stand by...
Old 01-15-14, 07:25 AM
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MSchuh....I removed the company names and pics of the estimates. Part of the Forum rules about no specific companies mentioned. I think your post is still clear and if the Pro's need specifics I'm sure they will ask. If you would like to re-post the pics with the company info redacted that would be fine.
Old 01-15-14, 03:19 PM
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How often do you use your fireplace? You could save money by closing it up and just replace the boiler's flue?

Or maybe install a gas log, and a small flue for it?
Old 01-15-14, 04:29 PM
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Replace the boiler with a direct vent (PVC or stainless) version so you don't need to use the chimney flue. It'll be more efficient than your converted 26 year old version. Use an indirect for your hot water.

Then do the gas fireplace insert with a concentric vent (stainless) down the chimney.

You'll only need to do structural repairs to the chimney at that point and maybe some repointing.
Old 01-15-14, 04:52 PM
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Yeah... not a bad idea Dan... spending that much money on the chimney (which may be somewhat 'overkill', but I can't see the camera shots down the flues, so could well be needed) seems kinda crazy.

Take that money into a more efficient boiler... and direct vent... if you can.

Would sorta come out as a win-win as long as money needs to be spent. Might come out close to the same expenditure but for a better/newer heating system.
Old 01-16-14, 07:54 AM
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Thanks for the replies. The fireplace would be last on my list at this point, have a whole lot of other things I need to do. More important is the heating solution...so you think I can do the direct vent heating system also to be used for hot water for under $5k?
Old 01-16-14, 08:38 AM
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so you think I can do the direct vent heating system also to be used for hot water for under $5k?
Not likely... but certainly less than the 'big' estimate.

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