Home Chimneys

[JTTHECLOCKMAN]

For those in the know about chimneys, a few questions. First I am talking homeowner chimneys. Forgive the not knowing names. But what are the red blocks that line the interior of a chimney. They are square and stack on top of each other and then block and or brick is built around them. 

The reason I am asking is there now a law that if you replace your boiler or hot water heater and it is piped into the chimney then you need to have a steel liner inserted???  I have conflicting reports that if you chimney is lined with terracotta bricks then it does because they can leak gases. But if you have these red blocks and for a lack of a better name clay blocks you do not. Anyone with knowledge of new rules when installing a new furnace and or water heater. Or do you know the rules to when you need to install a steel liner??  I will be needing to do this next year. Thanks.

[fixtureman]

Liner tile is what we call them

[TDKPE]

Clay flue liner tiles I believe is the proper designation, but I've heard it called several variations on that, like flue pipe, flue tile, liner tile, etc.  All the same thing, AFAIK.

I believe the reason for a SS liner is that the cold, large flue tile is too cold and too large to develop a good draft with the high efficiency water heaters and furnaces.  But I don't know that for fact.

Edit: Manufacturer's web page, for your edification. https://www.superiorclay.com/fireplaces/...ue-liners/

[arthropod98]

Clay flue liner tiles I believe is the proper designation, but I've heard it called several variations on that, like flue pipe, flue tile, liner tile, etc.  All the same thing, AFAIK.

I believe the reason for a SS liner is that the cold, large flue tile is too cold and too large to develop a good draft with the high efficiency water heaters and furnaces.  But I don't know that for fact.

Edit:  Manufacturer's web page, for your edification.  https://www.superiorclay.com/fireplaces/...ue-liners/

we definitely improved our draft for the woodstove when we got a liner.  it was 8" diameter "flue tile", so we were able to do 6" insulated liner  --  just an incredible improvement.

sorry to JT, but i'm just not sure the official name.  

[WoodCzech]

I had a liner installed way back in an old brick chimney. The issue there was that the exhaust from more efficient furnaces and heaters is cooler and contains more vapor. The brick flue didn't get hot enough to develop updraft and the moisture just condensed inside of the chimney and seeped through the bricks into the attic. And it was lot of brown water so it leaked through the ceiling and was a mess.

[carwashguy]

Anyone with knowledge of new rules when installing a new furnace and or water heater. Or do you know the rules to when you need to install a steel liner??  I will be needing to do this next year. Thanks.

Are you allowed to install a furnace that isn't 90%+ efficiency? AFAIK in my area high efficiency heating appliances are required.  That means PVC exhaust and fresh air intake.  80% eff water heaters are still allowed but I'd still recommend a heat pump water heater if possible.