Ok, explain this to me like I'm a 3 year old

[Bnub]

My furnace exhaust pipe that goes to a vent at the top of my roof if super fucking hot. Like, can't hold your hand to it for more than 1/2 a second.

Why am I letting that hot air go right out of the house? I realize it's exhaust and obviously I don't want that air going into my house, but shouldn't it be passed through another set of coils or something?

Like, ideally, wouldn't I want the temperature of that exhaust to be as cold as possible, meaning I've extracted every single Kelvin of energy from the combustion?

Enlighten me.

[Master Splinter]

First of all, how did you figure this out?

Secondly, PM me a picture of your wife's pussy.

[atb12688]

Your furnace is masturbating. You have to take the computer away.

[East Side Jackalope]

My furnace exhaust pipe that goes to a vent at the top of my roof if super fucking hot. Like, can't hold your hand to it for more than 1/2 a second.

Why am I letting that hot air go right out of the house? I realize it's exhaust and obviously I don't want that air going into my house, but shouldn't it be passed through another set of coils or something?

Like, ideally, wouldn't I want the temperature of that exhaust to be as cold as possible, meaning I've extracted every single Kelvin of energy from the combustion?

Enlighten me.

It keeps your furnace from burning the fuck up.

[flatlander]

Exhaust can only be safely cooled so much before the nastier shit will condense out and corrode the hell out of your exhaust piping. But what you're describing is waste heat recovery and is used at many industrial sites. At those places, the added cost of the equipment is easily offset by the savings in operating costs.

[crsman2]

Just pay your fuckin bill.

[East Side Jackalope]

Exhaust can only be safely cooled so much before the nastier shit will condense out and corrode the hell out of your exhaust piping. But what you're describing is waste heat recovery and is used at many industrial sites. At those places, the added cost of the equipment is easily offset by the savings in operating costs.

Yeah, thought I said that.

[Master Splinter]

still waiting....

[st. louisville cards]

My furnace exhaust pipe that goes to a vent at the top of my roof if super fucking hot. Like, can't hold your hand to it for more than 1/2 a second.

Why am I letting that hot air go right out of the house? I realize it's exhaust and obviously I don't want that air going into my house, but shouldn't it be passed through another set of coils or something?

Like, ideally, wouldn't I want the temperature of that exhaust to be as cold as possible, meaning I've extracted every single Kelvin of energy from the combustion?

Enlighten me.

You have an 80% efficiency (or less) furnace. A more efficient 90% (or more) furnace does have a secondary heat exchanger where it recaptures that heat before expelling it out yo house. So you've got a furnace that operates on old technology.

[rutkap]

what I would do is put a cooler on top of that mother fucker. this way you can heat your meatwater with the same energy that you heat your house.

[Cheezy E]

First of all, how did you figure this out?

Secondly, PM me a picture of your wife's pussy.

still waiting....

Ha. Splinter tots got drunk at his neighborhood happy hour.

[Bnub]

You have an 80% efficiency (or less) furnace. A more efficient 90% (or more) furnace does have a secondary heat exchanger where it recaptures that heat before expelling it out yo house. So you've got a furnace that operates on old technology.

That's just dumb. Why would anyone design anything less?

"Hurm, we're gonna design this furnace so that only some of the heat gets transferred into the house. We don't need ALL the heat, just some"

dumb.

[Master Splinter]

Ha. Splinter tots got drunk at his neighborhood happy hour.

Yes, Yes I did.

[rutkap]

That's just dumb. Why would anyone design anything less?

"Hurm, we're gonna design this furnace so that only some of the heat gets transferred into the house. We don't need ALL the heat, just some"

dumb.

thing is a lot of stuff gets built up in chimneys. the more you constrict it the more it clogs. If you let it build up enough, it becomes flammable and can catch on fire. putting bends and shit in there makes it more difficult to clean and easier for deposits to build up.

[108 Stitches]

I was thinking about building a kick ass dog house a few years ago, and I was considering routing the vent pipe for the dryer through it to provide heat. In the end I decided this was extremely hoosier, so I got a steel dog crate and stuck it in the basement.

[st. louisville cards]

That's just dumb. Why would anyone design anything less?

"Hurm, we're gonna design this furnace so that only some of the heat gets transferred into the house. We don't need ALL the heat, just some"

dumb.

Its technology from before the 60's, when conservation and price started to factor in. So yes, there weren't worries about the wasted heat and the technology wasn't there, they still had to find ways to safely recapture the exhaust, it is being expelled from the home for a reason. It costs about $500 more for a 90% furnace today, the gap would have been wider when 90% furnaces weren't produced as much.
It is wasteful, but so were cars that got 8-10 miles per gallon and we had those until gas prices became an issue and air pollution became an issue. Plus gas heating systems were replacing coal systems which were about half as efficient. So in the 50's or 60's if a home owner changed their heat from coal to gas and their efficiency went from 40% to 80%, I imagine most homeowners wouldn't want to buck up for that extra 10% when they already got the majority of their cost savings.

[Bnub]

Its technology from before the 60's, when conservation and price started to factor in. So yes, there weren't worries about the wasted heat and the technology wasn't there, they still had to find ways to safely recapture the exhaust, it is being expelled from the home for a reason. It costs about $500 more for a 90% furnace today, the gap would have been wider when 90% furnaces weren't produced as much.
It is wasteful, but so were cars that got 8-10 miles per gallon and we had those until gas prices became an issue and air pollution became an issue. Plus gas heating systems were replacing coal systems which were about half as efficient. So in the 50's or 60's if a home owner changed their heat from coal to gas and their efficiency went from 40% to 80%, I imagine most homeowners wouldn't want to buck up for that extra 10% when they already got the majority of their cost savings.

I'd understand that if my home were built in the 60's. My was built 10 years ago.

[108 Stitches]

I'd understand that if my home were built in the 60's. My was built 10 years ago.

And you or whoever approved the design for it decided at that time to go with a cheaper unit. I'm sure Obama will give you some free cash if you upgrade your furnace to a more efficient model.

[Johnny Utah]

I'd understand that if my home were built in the 60's. My was built 10 years ago.

New houses are built like shit.

[Master Splinter]

I'd understand that if my home were built in the 60's. My was built 10 years ago.

Then, I'd guess the builder was saving money. Ours is the same way. It's one of those things you can probably upgrade when you build, but no one is thinking about that. Most people are worried about carpet color and cabinet types and shit like that.

[st. louisville cards]

I'd understand that if my home were built in the 60's. My was built 10 years ago.

And you or whoever approved the design for it decided at that time to go with a cheaper unit. I'm sure Obama will give you some free cash if you upgrade your furnace to a more efficient model.

This, most home builders (especially when they are building houses in a development) only put upgrades that the buyer can see (hardwood floors, granite counter top, etc). So your furnace, air conditioner, water heater, insulation, tend to be bottom of the line.

[BfromV]

Yeah, the current government mandated minimum efficiencies in HVAC systems only was handed down a few years ago or so. Can't remember the exact year off the top of my head.

[st. louisville cards]

Yeah, the current government mandated minimum efficiencies in HVAC systems only was handed down a few years ago or so. Can't remember the exact year off the top of my head.

The recent efficiency change was about 4 years ago and it was only related to Air Conditioners. Its been 20 years or so since they mandated to 80% efficiency on furnaces.

[PhishHook]

Builders grade materials = crap.
One issue is that the exhaust has to be hot enough to rise and leave the vent, if it is cooled too much the exhaust could back down and become a very large safety issue.

I had to ask and push to get a larger capacity hot water heater when I built my house, as others have said, they push the cosmetic upgrades probably because there is more profit in them for the builder.

[BfromV]

The recent efficiency change was about 4 years ago and it was only related to Air Conditioners. Its been 20 years or so since they mandated to 80% efficiency on furnaces.

Yup. You're right. My bad.

I'm shocked that they haven't mandated furnaces to be more efficient.

[Leon]

Kelvin is not a unit of energy.

[crsman2]

Kelvin is not a unit of energy.

http://www.awesomehq.com/wp-content/uploads/2010/07/mrwizard.jpg