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Racine16

New Member
Sep 13, 2021
18
NJ
I recently purchased a home with a chimney...it is used for both a wood burning fireplace and the furnace. one of the caps was missing so I had it replaced and had them look at the chimney as I was aware it needed mason work at a minimum. I must add I do not ever plan to burn wood as my son and I have asthma. The guy who capped the chimney said not to use the fireplace (not an issue). He said it needs a lot of work up on the roof and that the liner is not the correct size for the furnace I have. He also said the size I need for my furnace would not fit in the current chimney. I explained I’m in the process of replacing the furnace and he said to get the specs and he will try to help. My plumber insists there is no issue and the furnace has been there using that fireplace for 30 years. Now the plumber is having a disagreement with the town inspector regarding the BTUs so I’m assuming the chimney guy was correct. The plumber is saying it meets code and certifying it. My question is what is the most cost effective way to resolve this as I suspect I will need to make some correction to this fireplace to make it safe to vent my gas furnace. Funds are limited but I need my house safe and I am very concerned about how this can be resolved.
 

gthomas785

Minister of Fire
Feb 8, 2020
500
Central MA
Get the manual for the furnace and find out what it requires for venting, and compare that to what you have.
If you are replacing anyway, the new 90+% furnaces will need a plastic vent pipe so the current liner would be a moot issue unless it's already plastic.
 

Racine16

New Member
Sep 13, 2021
18
NJ
Get the manual for the furnace and find out what it requires for venting, and compare that to what you have.
If you are replacing anyway, the new 90+% furnaces will need a plastic vent pipe so the current liner would be a moot issue unless it's already plastic.
Thanks for your response...will try to obtain this info
 

moresnow

Minister of Fire
Jan 13, 2015
1,783
Iowa
Isn't the new furnace to be power vented with plastic up and out? Add some details. Where is the new furnace being installed etc. Natural gas, L.P., Oil?
 

Racine16

New Member
Sep 13, 2021
18
NJ
Isn't the new furnace to be power vented with plastic up and out? Add some details. Where is the new furnace being installed etc. Natural gas, L.P., Oil?
Some details...we recently purchased the home...the furnace was 30 years old and past it’s life...It is a gas furnace being replaced by a new gas furnace...it is located in the basement. The current chimney in the house has 2 compartments...one vents the furnace...the other vents the wood burning fireplace on the first floor. I have an inspection report and video but I believe the video is only for the fireplace flue...I will attach the report as some pics are included. Currently the old furnace is removed...I have a picture of it but not sure that sheds much light and have to find out exactly what product will be replacing it. I have no expertise with regard to plumbing or chimneys so any guidance is appreciated.

A369A136-940F-4987-97B6-CCCDBFC345EF.png 1D64E8C0-50D7-49AE-AC7B-EA11D3E69133.png DB6C716D-E8F2-42F6-8AA5-F87FAB923BCF.png 631C016C-124B-474C-86C3-F7EF4521836E.png B0A94E55-4B4A-4ECB-9ED5-F392BA9B322F.png 0E49F890-CACB-4EC6-AC54-F4F99E7EBC9E.png 5F7948FD-D10A-4BF2-A98D-5A8EC899BC02.png E18799A9-98FC-4568-95FB-4ED88FF487FB.png 2E44226B-1458-48AA-A58B-52900611B871.png 32823B0D-BD6D-4139-A18B-4013BBB7C7A4.png 2CAA9A37-23E9-49A2-ACF5-FE937BED5550.png
 

moresnow

Minister of Fire
Jan 13, 2015
1,783
Iowa
I can only say that I had to replace a basement L.P. gas furnace a few years back and it was power vented with PVC vertically up to the ceiling and then horizontally out the side of the house just above the concrete foundation. Since then I have helped with 2 more of these exact same installs. Not sure why yours would be different?
I actually tore down my masonry/brick/failing/leaking chimney below roof level afterwards. No more masonry chimney worries. Done!
 
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Racine16

New Member
Sep 13, 2021
18
NJ
I can only say that I had to replace a basement L.P. gas furnace a few years back and it was power vented with PVC vertically up to the ceiling and then horizontally out the side of the house just above the concrete foundation. Since then I have helped with 2 more of these exact same installs. Not sure why yours would be different?
I actually tore down my masonry/brick/failing/leaking chimney below roof level afterwards. No more masonry chimney worries. Done!
I can only say that I had to replace a basement L.P. gas furnace a few years back and it was power vented with PVC vertically up to the ceiling and then horizontally out the side of the house just above the concrete foundation. Since then I have helped with 2 more of these exact same installs. Not sure why yours would be different?
I actually tore down my masonry/brick/failing/leaking chimney below roof level afterwards. No more masonry chimney worries. Done!
The mason I consulted mentioned it may be more cost effective to vent out the side of the house as opposed to fixing masonry ...it’s an older house with an addition so I guess it was just always vented up the chimney...my plumber seems to want to fight with the inspector and is having the “no one is gonna push me around” attitude ... how low did you take out the masonry And what did you do with the rest of your chimney? The mason said we would have to patch in siding and it probably wouldn’t match so I’m thinking he was suggesting tear it all out...probably because we have no intention of using the fireplace either. That sounds insanely expensive and I assume I need a structural enginer for that mess.
 

Racine16

New Member
Sep 13, 2021
18
NJ
Get the manual for the furnace and find out what it requires for venting, and compare that to what you have.
If you are replacing anyway, the new 90+% furnaces will need a plastic vent pipe so the current liner would be a moot issue unless it's already plastic.
Here is the new furnace...it’s not plastic and looks like water heater and furnace go to chimney

52EF7CA3-9731-4D4B-BEE1-122790B3E6B4.jpeg 494E5A08-DA8E-47DB-BB7B-E879F7183811.jpeg FA029970-556A-46BF-9A6C-EAE41FA05774.jpeg
 

moresnow

Minister of Fire
Jan 13, 2015
1,783
Iowa
The mason I consulted mentioned it may be more cost effective to vent out the side of the house as opposed to fixing masonry ...it’s an older house with an addition so I guess it was just always vented up the chimney...my plumber seems to want to fight with the inspector and is having the “no one is gonna push me around” attitude ... how low did you take out the masonry And what did you do with the rest of your chimney? The mason said we would have to patch in siding and it probably wouldn’t match so I’m thinking he was suggesting tear it all out...probably because we have no intention of using the fireplace either. That sounds insanely expensive and I assume I need a structural enginer for that mess.
You have a boiler setup that I completely missed in your info/pics. I was speaking about forced air systems. Different animal. My comments likely have zero bearing on your situation. Apologies if I wasted your time!
 
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ABMax24

Minister of Fire
Sep 18, 2019
1,071
Grande Prairie, Alberta, Canada
Just to clarify that is a boiler, not a furnace.

Why is the plumber installing an ~80% efficient boiler, when there are far better 95% efficient condensing boilers available? You could have even got a combination boiler/water heater and got rid of your water tank too.

These condensing boilers are also direct vent using PVC and are commonly vented out the wall, which would avoid your chimney issues.
 

Racine16

New Member
Sep 13, 2021
18
NJ
You have a boiler setup that I completely missed in your info/pics. I was speaking about forced air systems. Different animal. My comments likely have zero bearing on your situation. Apologies if I wasted your time!
No worries
Just to clarify that is a boiler, not a furnace.

Why is the plumber installing an ~80% efficient boiler, when there are far better 95% efficient condensing boilers available? You could have even got a combination boiler/water heater and got rid of your water tank too.
My bad for calling it a furnace....I didn’t realize. I know the water heater is only a few years old. I have no idea why he chose the less energy efficient boiler...after I had the chimney capped and that guy took a peak and said the chimney was too small for liner I would need I asked the plumber what type of boiler he ordered and if it was energy efficient and he said no he didn’t find it really makes a difference. That was the answer received. Again since I have no plumbing knowledge i feel like I’m stuck in the middle of a mess of confusion here And I’m concerned it could cost me both safety and money.
 

Racine16

New Member
Sep 13, 2021
18
NJ
You have a boiler setup that I completely missed in your info/pics. I was speaking about forced air systems. Different animal. My comments likely have zero bearing on your situation. Apologies if I wasted your time!
No worries...lol...apparently I was calling a boiler a furnace...I’m a bit clueless and stressed...thanks for trying to help
 

ABMax24

Minister of Fire
Sep 18, 2019
1,071
Grande Prairie, Alberta, Canada
No worries

My bad for calling it a furnace....I didn’t realize. I know the water heater is only a few years old. I have no idea why he chose the less energy efficient boiler...after I had the chimney capped and that guy took a peak and said the chimney was too small for liner I would need I asked the plumber what type of boiler he ordered and if it was energy efficient and he said no he didn’t find it really makes a difference. That was the answer received. Again since I have no plumbing knowledge i feel like I’m stuck in the middle of a mess of confusion here And I’m concerned it could cost me both safety and money.

He's right that you probably won't notice much on your bill. Maybe he thought that the labor would be cheaper this way, but if you need extensive chimney work this won't be the case.

If the inspector says the current install is a no go, ask the plumber what it would cost to swap that boiler for a direct vent condensing type, at the end of the day he/she installed a boiler that does not conform to code and should be at least partly on the hook for the costs to make it right.

The majority of our local plumbers install Navien brand condensing boilers (I have a Navien hotwater heater in my house), and from what I can see online are similar in price range to the boiler your plumber installed, this may be a cheaper option to have the venting run out the wall. There will of course be piping modifications required to hook this up.

Here is their site, Navien is not the only maker of these boilers by any means, it's just the brand I'm familiar with:
 

Racine16

New Member
Sep 13, 2021
18
NJ
He's right that you probably won't notice much on your bill. Maybe he thought that the labor would be cheaper this way, but if you need extensive chimney work this won't be the case.

If the inspector says the current install is a no go, ask the plumber what it would cost to swap that boiler for a direct vent condensing type, at the end of the day he/she installed a boiler that does not conform to code and should be at least partly on the hook for the costs to make it right.

The majority of our local plumbers install Navien brand condensing boilers (I have a Navien hotwater heater in my house), and from what I can see online are similar in price range to the boiler your plumber installed, this may be a cheaper option to have the venting run out the wall. There will of course be piping modifications required to hook this up.

Here is their site, Navien is not the only maker of these boilers by any means, it's just the brand I'm familiar with:
Thanks! I’ll check it out! So if the inspector passes it should I not worry? I don’t want to have a C02 issue...I assume that could be a problem but again I don’t know much andI have a 5 year old So I worry. Also is there a way to vent this traditional style boiler anyway other than through this old chimney or would swapping for the condensing boiler be the only way?
 

Millbilly

Feeling the Heat
Dec 13, 2015
291
02648
Were there no rebates in your state for efficiency direct vent condensing boilers? Like stated above I would have gone with a combo unit and had it vented out of the side of the house and abandoned the masonry chimney.
 

ABMax24

Minister of Fire
Sep 18, 2019
1,071
Grande Prairie, Alberta, Canada
Thanks! I’ll check it out! So if the inspector passes it should I not worry? I don’t want to have a C02 issue...I assume that could be a problem but again I don’t know much andI have a 5 year old So I worry. Also is there a way to vent this traditional style boiler anyway other than through this old chimney or would swapping for the condensing boiler be the only way?

If the inspector passes it, then it should be fine because it meets code. Right now it sounds like the inspector doesn't want to pass the install because the chimney is too small to meet code.

I'm not a chimney expert, but to my understanding this type of appliance needs to be vented up to the roofline, it relies on the heat from the flue gases to draw them up and out of the house, this has to happen either through the existing chimney or through a new one. It can't be just vented out the wall.

This is where a condensing boiler differs, it cools the flue gases down enough that it can safely be vented through PVC pipe. The system doesn't operate on draft and instead uses a blower within the boiler to pull in fresh combustion air and to push the burnt gases outside, making wall vents possible.

As far as CO goes, all houses should have a carbon monoxide detector installed in them for this possibility. I have 4 in my house, one per floor with an additional beside the furnace and hot water heater. I have an extra in the basement, and it will be put in our daughter's room when she is born sometime the beginning of November.
 

Racine16

New Member
Sep 13, 2021
18
NJ
Were there no rebates in your state for efficiency direct vent condensing boilers? Like stated above I would have gone with a combo unit and had it vented out of the side of the house and abandoned the masonry chimney.
Hindsight is 2020...I just followed the lead of the plumber knowing nothing myself of the issue unfortunately. I simply hired him to replace the boiler. Then while getting the chimney capped and asking about masonry repair I was enlightened regarding the chimney issue. And how the boiler could pose an issue, When I brought it to the plumbers attention he had already ordered the boiler and he said the chimney was fine and he would certify it....He said the previous boiler had been there for 30 years with no issues...and that Is where we are now however I heard the inspector was pushing back causing me concern as I want to be sure it is safe
 

gthomas785

Minister of Fire
Feb 8, 2020
500
Central MA
That is a fine boiler.. there are many reasons to go with the lower efficiency. Depending on your fuel costs and heat load you may not get much savings from a higher efficiency one, and also your service calls will be cheaper and easier with the 80% unit.

This boiler requires a type I vent which is negative pressure non-condensing. A natural draft chimney works for this, or you can vent it through the wall with a power venter.
 

Racine16

New Member
Sep 13, 2021
18
NJ
That is a fine boiler.. there are many reasons to go with the lower efficiency. Depending on your fuel costs and heat load you may not get much savings from a higher efficiency one, and also your service calls will be cheaper and easier with the 80% unit.

This boiler requires a type I vent which is negative pressure non-condensing. A natural draft chimney works for this, or you can vent it through the wall with a power venter.
Ahhh....I see...I will have to see how the chimney situation pans out and do a cost comparison of that vs changing to a power vent if extensive chimney repair is required. If the inspector passes it as is do you think I can just move on without concern?
 

Racine16

New Member
Sep 13, 2021
18
NJ
If the inspector passes it, then it should be fine because it meets code. Right now it sounds like the inspector doesn't want to pass the install because the chimney is too small to meet code.

I'm not a chimney expert, but to my understanding this type of appliance needs to be vented up to the roofline, it relies on the heat from the flue gases to draw them up and out of the house, this has to happen either through the existing chimney or through a new one. It can't be just vented out the wall.

This is where a condensing boiler differs, it cools the flue gases down enough that it can safely be vented through PVC pipe. The system doesn't operate on draft and instead uses a blower within the boiler to pull in fresh combustion air and to push the burnt gases outside, making wall vents possible.

As far as CO goes, all houses should have a carbon monoxide detector installed in them for this possibility. I have 4 in my house, one per floor with an additional beside the furnace and hot water heater. I have an extra in the basement, and it will be put in our daughter's room when she is born sometime the beginning of November.
 

gthomas785

Minister of Fire
Feb 8, 2020
500
Central MA
Ahhh....I see...I will have to see how the chimney situation pans out and do a cost comparison of that vs changing to a power vent if extensive chimney repair is required. If the inspector passes it as is do you think I can just move on without concern?
Yes I would think so. I don't know about the rules where you live but in my area the plumber who installs it should perform a combustion test and a draft measurement. If all of those are in spec for the appliance then you are good to go. If the liner is indeed too small then the draft reading will be low.

Since you mentioned being concerned about carbon monoxide I would recommend getting a CO detector and put it near the furnace boiler. That way if you do happen to have any draft issues you will know immediately.
 
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Racine16

New Member
Sep 13, 2021
18
NJ
I see...I guess maybe the chimney was considered to be fine for the old boiler but maybe code changed. The fire inspectors passed the CO2 detector requirement during the home sale but I think I will add some more for peace of mind
If the inspector passes it, then it should be fine because it meets code. Right now it sounds like the inspector doesn't want to pass the install because the chimney is too small to meet code.

I'm not a chimney expert, but to my understanding this type of appliance needs to be vented up to the roofline, it relies on the heat from the flue gases to draw them up and out of the house, this has to happen either through the existing chimney or through a new one. It can't be just vented out the wall.

This is where a condensing boiler differs, it cools the flue gases down enough that it can safely be vented through PVC pipe. The system doesn't operate on draft and instead uses a blower within the boiler to pull in fresh combustion air and to push the burnt gases outside, making wall vents possible.

As far as CO goes, all houses should have a carbon monoxide detector installed in them for this possibility. I have 4 in my house, one per floor with an additional beside the furnace and hot water heater. I have an extra in the basement, and it will be put in our daughter's room when she is born sometime the beginning of November.
 

Racine16

New Member
Sep 13, 2021
18
NJ
Yes I would think so. I don't know about the rules where you live but in my area the plumber who installs it should perform a combustion test and a draft measurement. If all of those are in spec for the appliance then you are good to go. If the liner is indeed too small then the draft reading will be low.

Since you mentioned being concerned about carbon monoxide I would recommend getting a CO detector and put it near the furnace. That way if you do happen to have any draft issues you will know immediately.
Ok...thanks...hopefully that is the case here in NJ as well. I’m definitely gonna grab a few more CO2 detectors for the basement and make sure all gas appliances have one nearby.
 

Millbilly

Feeling the Heat
Dec 13, 2015
291
02648
Not to be a stickler for wording, but there is just one oxygen molecule.
 
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