How to design a garage with ventilation for remote start?

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
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Moving next year; new place will either have a garage or the room to build one. Was wondering about remote start & carbon monoxide - how do you ventilate a garage, while still keeping it sealed from the elements? I've read that people have died from carbon monoxide when their remote car starter went off & ended up running for an extended period of time:

http://priuschat.com/threads/warnin...-store-your-car-in-an-attached-garage.128203/

I have seen aftermarket garage heaters, like from Modine, so you could keep the garage heated in the winter if you're doing workshop stuff, which would take care of cold air from the ventilation system:

http://www.modinehvac.com/web/Hot-Dawg.htm

Anyway, what's the best approach for that? It'd be nice to remote start the car on cold mornings in the garage to warm it up, without having to have a heater running and without filling up the air with unventilated exhaust fumes. Is that even doable without an active air exchange system?
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
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Wow actually, it looks like it's never a good idea to remote-start a car in a garage, even if the door is open:

http://priuschat.com/threads/warnin...ar-in-an-attached-garage.128203/#post-1827082

I think most remote starts come with a 15-minute cutoff, but this is saying things get bad even after 7 or 8 minutes.

When building a new home, how should I protect against carbon monoxide from the garage? There are no approved, standard methods. The American Lung Association suggests building a detached garage. Other possible solutions include: tightly sealing walls and doors to the house, or using an exhaust fan in the garage. The main means to protect yourself from CO from the garage are:

*Install a CO detector in the house.
* Never run a vehicle in the garage any longer than the time required to move it out of the garage.

So it sounds like the best options are:

1. Build a detached garage for maximum safety
2. Install a pair of doors to act as a breezeway (still takes 5 minutes to clear out CO2)
3. Have an exhaust fan in the garage

Not that it's a huge deal or anything, but on the days when it's 0F & snowing outside, it'd be nice to park in a garage & come out to a warm car. Doesn't look like there are any super great solutions short of keeping the garage heated or having some sort of active exhaust fan system installed.
 

cabri

Diamond Member
Nov 3, 2012
3,616
1
81
Unless the garage is air tight there will be able to have airflow with some ventilation system.

Choices could be:
Have an exhaust hose that you connect to the tail pipe and connect to a output hole that has a pressure (spring loaded) flap.
Open up the garage door prior to starting the vehicle. Do you want a warm vehicle of a warm garage?
Install an exhaust fan that you turn on (again with a flap).

Daughter has a 2 vehicle attached garage that has a vent from the house heating system. Never gets below 45-50 even with temp below 0F. That makes the vehicles tolerable to use in the AM. Workbench area at the front has an overhead electric radiant heater if needed.
 

Raizinman

Platinum Member
Sep 7, 2007
2,355
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meettomy.site
I have one HVAC duct running to my garage for heating in the winter and cooling in the summer. I also have an external gas heater for those extra cold days. This heater does not require ventilation, see Northern Hydraulic if you wish to purchase one. In the summer the concrete retains the cold and keeps the garage a few degrees cooler. Insulating the garage is also helpful, both walls and ceiling.
 

JulesMaximus

No Lifer
Jul 3, 2003
74,542
921
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Man, people these days are a bunch of pussies. I remember winters in Rochester, NY, I had an old car with poor weather stripping and a heater that didn't work. I'd drive that car from Rochester to Albany in the middle of winter with no heat. I would just bundle up and drive straight through... I could do that drive in 3.5 hours door to door (I lived in Greece and was traveling to East Greenbush).

BTW-I installed CO detectors in my house (one upstairs and one downstairs). Our heater is in the garage and it is a forced air system. I would never want to run a car in there with the door closed but I also live in a warm climate so heat is something I rarely use anyway.
 
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Zargon

Lifer
Nov 3, 2009
12,218
2
76
Moving next year; new place will either have a garage or the room to build one. Was wondering about remote start & carbon monoxide - how do you ventilate a garage, while still keeping it sealed from the elements? I've read that people have died from carbon monoxide when their remote car starter went off & ended up running for an extended period of time:

http://priuschat.com/threads/warnin...-store-your-car-in-an-attached-garage.128203/

I have seen aftermarket garage heaters, like from Modine, so you could keep the garage heated in the winter if you're doing workshop stuff, which would take care of cold air from the ventilation system:

http://www.modinehvac.com/web/Hot-Dawg.htm

Anyway, what's the best approach for that? It'd be nice to remote start the car on cold mornings in the garage to warm it up, without having to have a heater running and without filling up the air with unventilated exhaust fumes. Is that even doable without an active air exchange system?

they idled the car, till it ran out of gas. that's a LONG ASS TIME dude

the house probably wasn't sealed well either

newer houses it will be due to code issues


but seriously, if its in the garage, why do you need to idle it for very long? also...open the garage door?
 

LTC8K6

Lifer
Mar 10, 2004
28,520
1,575
126
Modern engines in good running order put out so little CO that it's barely a problem. It's actually difficult to kill yourself by idling a modern car in an enclosed space.

A modern remote started engine idling for 15 minutes shouldn't be any problem at all.

Put a CO detector in the garage and do a few tests to see what happens. Keep it in there for safety.

I doubt you will see high CO levels with 15 minutes of idling.
 

Midwayman

Diamond Member
Jan 28, 2000
5,723
325
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they idled the car, till it ran out of gas. that's a LONG ASS TIME dude

the house probably wasn't sealed well either

newer houses it will be due to code issues


but seriously, if its in the garage, why do you need to idle it for very long? also...open the garage door?

It was an accident. Its not terribly hard to sit on your keys wrong and start your car. The key is a starter that only idles for a short period (most if not all nowdays) and install carbon monoxide detectors in your house. You should have them anyways.
 

monkeydelmagico

Diamond Member
Nov 16, 2011
3,961
145
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Wait what? You don't have a garage now but your worried about how your going to warm up your car in one? Holy hypothetical hypothermia batman
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
5,825
136
Unless the garage is air tight there will be able to have airflow with some ventilation system.

Choices could be:
Have an exhaust hose that you connect to the tail pipe and connect to a output hole that has a pressure (spring loaded) flap.
Open up the garage door prior to starting the vehicle. Do you want a warm vehicle of a warm garage?
Install an exhaust fan that you turn on (again with a flap).

Daughter has a 2 vehicle attached garage that has a vent from the house heating system. Never gets below 45-50 even with temp below 0F. That makes the vehicles tolerable to use in the AM. Workbench area at the front has an overhead electric radiant heater if needed.

Yeah, that's one of the unknown variables right now - moving into a starter house next year once I wrap up school this year, don't know if I'll find one with a garage or not. I would like an attached 2-car garage. The plan is to overhaul the house with a mini-split ductless system (basically individual room zoned HVAC via Mitsubishi Mr. Slim units), so there wouldn't be a central heating system.

I could add a Mr. Slim specifically to the garage, but it's one of those questions of heat up the garage vs. just remote start the car to heat up the car. It'd be easier to just remote-start the car & have it warm up, instead of paying to heat up the garage, but the concern becomes the exhaust. I don't know enough about ventilation to know how much of an issue that would be.
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
5,825
136
I have one HVAC duct running to my garage for heating in the winter and cooling in the summer. I also have an external gas heater for those extra cold days. This heater does not require ventilation, see Northern Hydraulic if you wish to purchase one. In the summer the concrete retains the cold and keeps the garage a few degrees cooler. Insulating the garage is also helpful, both walls and ceiling.

Thanks, any particular model to look into? I'm not sure if this will be a combination workshop/parking garage or parking-only. Depends on if I have to build one or not :D
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
5,825
136
Man, people these days are a bunch of pansies. I remember winters in Rochester, NY, I had an old car with poor weather stripping and a heater that didn't work. I'd drive that car from Rochester to Albany in the middle of winter with no heat. I would just bundle up and drive straight through... I could do that drive in 3.5 hours door to door (I lived in Greece and was traveling to East Greenbush).

BTW-I installed CO detectors in my house (one upstairs and one downstairs). Our heater is in the garage and it is a forced air system. I would never want to run a car in there with the door closed but I also live in a warm climate so heat is something I rarely use anyway.

It's a nice convenience feature, especially when you have little kids - press the button, warm up the car, keep it in the garage so there's nice ice or snow to scrape off. Some caveats of starting in a garage are listed here:

http://priuschat.com/threads/warnin...ar-in-an-attached-garage.128203/#post-1827082

Two notes in particular:

What happens when CO from the garage enters the house?

The garage serves as a large source of carbon monoxide. As the CO leaks into the house it is diluted, so CO concentrations in the house are less than those in the garage. It can take several hours for CO concentrations in the home to reach the maximum reached. Often CO detectors alarm several hours after the vehicle left the garage. Persons in the house, especially those in all day, might experience typical CO symptoms such as headache or flu-like symptoms.

Can I place a CO detector or alarm in the garage to warm me of excessive CO?

No. Residential detectors are not designed or approved to operate in garage conditions. Temperatures and humidity variations are too large, and the high start-up amounts of carbon monoxide can easily damage or destroy the sensing cell. CO detectors should never be placed or used in the garage.

So basically, there can be a time-delay effect into the house, and residential CO2 detectors are effective in garages. Again, it's not like it's a huge deal, just a convenience feature, but I'd rather understand the situation completely before diving in too deep.
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
5,825
136
they idled the car, till it ran out of gas. that's a LONG TIME dude

the house probably wasn't sealed well either

newer houses it will be due to code issues


but seriously, if its in the garage, why do you need to idle it for very long? also...open the garage door?

Yeah, and as mentioned earlier, I think most automatic car starters only run the engine for 15 minutes max these days, so it's not like it'll just sit there & idle all night long under normal circumstances.

I don't know enough about housing codes to know how well the newer sealing would affect garages & CO2 entrapment. I try to base my research off hard data, which hasn't been easy to find, although there are a lot of reports on google of people getting sick (or dying) from over-exposure to CO2.

We had a long winter in my area, between 0F and 10F a lot of the time with a ton of snow, ice, and cold rain, so I'd prefer to start it up & keep the garage door closed if possible. That way I could walk out to a warm car that I don't have to scrape off, especially when loading a baby & baby gear into the vehicle. It's a convenience thing.
 

JCH13

Diamond Member
Sep 14, 2010
4,981
66
91
This is how fire engines and other large emergency vehicles deal with this problem:

sft.jpg


Break-away vent tube (magnetic?) connected right to the exhaust with a super high-flowing exhaust fan that can out-perform the vehicles' exhaust production.

Heating the garage itself is probably a better option, all things considered.
 

eldorado99

Lifer
Feb 16, 2004
36,324
3,163
126
Has nobody in this place ever heard of a fucking block heater?

You guys are way over thinking things here.
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
5,825
136
Modern engines in good running order put out so little CO that it's barely a problem. It's actually difficult to kill yourself by idling a modern car in an enclosed space.

A modern remote started engine idling for 15 minutes shouldn't be any problem at all.

Put a CO detector in the garage and do a few tests to see what happens. Keep it in there for safety.

I doubt you will see high CO levels with 15 minutes of idling.

Interesting, I didn't realize newer cars were that efficient, good to know.
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
5,825
136
Wait what? You don't have a garage now but your worried about how your going to warm up your car in one? Holy hypothetical hypothermia batman

Well, you know, finish college, settle down, yada yada yada - this is Anandtech, after all - where we are geeks & over-analyze everything ;)
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
5,825
136
Has nobody in this place ever heard of a block heater?

You guys are way over thinking things here.

Never used a block heater, I thought those only warmed up the engine - does it help warm up the car interior too?
 

Zargon

Lifer
Nov 3, 2009
12,218
2
76
It was an accident. Its not terribly hard to sit on your keys wrong and start your car. The key is a starter that only idles for a short period (most if not all nowdays) and install carbon monoxide detectors in your house. You should have them anyways.

I have CO detectors already yeah

you usually have to hit the button twice to get Remote Start to work, in quick succession. they probably had an aftermarket if it didn't have a cut off I would guess.

no idea how people keep keys in their back pockets tho :p

Has nobody in this place ever heard of a fucking block heater?

You guys are way over thinking things here.

not as nice as remote start, ie cant plug in at work in the winter ETC ETC
 

Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,274
5,825
136
This is how fire engines and other large emergency vehicles deal with this problem:

sft.jpg


Break-away vent tube (magnetic?) connected right to the exhaust with a super high-flowing exhaust fan that can out-perform the vehicles' exhaust production.

Heating the garage itself is probably a better option, all things considered.

Yikes, I think I'll avoid having to plug in an exhaust pipe :D

I'm sure zillions of people remote-start in their garage every day, I just want to make sure I understand any risks involved. Heating the garage might be the safest & easiest way to go. But if I go with a mini-split ductless HVAC system, that would mean having a dedicated heater just for the garage. Just to keep the car warm. Which makes ventilation seem like a better option, haha.
 
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JulesMaximus

No Lifer
Jul 3, 2003
74,542
921
126
Interesting, I didn't realize newer cars were that efficient, good to know.

I wouldn't trust my life with what LTC8K6 posted.

Modern automobiles, even with electronically-controlled combustion and catalytic converters, can still produce levels of carbon monoxide which will kill if enclosed within a garage or if the tailpipe is obstructed (for example, by snow) and exhaust gas cannot escape normally.
 

shabby

Diamond Member
Oct 9, 1999
5,782
45
91
Moving next year; new place will either have a garage or the room to build one.

If the garage is inside the house with living space behind two walls and the ceiling then it won't be that cold inside, even if its an exterior garage it'll still be better than having the car outside. Unless you're moving to alaska there really isn't a need to warm up the car inside a garage.
 

Zargon

Lifer
Nov 3, 2009
12,218
2
76
I wouldn't trust my life with what LTC8K6 posted.

Modern automobiles, even with electronically-controlled combustion and catalytic converters, can still produce levels of carbon monoxide which will kill if enclosed within a garage or if the tailpipe is obstructed (for example, by snow) and exhaust gas cannot escape normally.

after what time period though?

either way, I crack the garage door when I run something in the garage if its warming up, and open the door fully before going out there, that's what remotes are for...after all
 

boomerang

Lifer
Jun 19, 2000
18,883
641
126
My attached garage rarely gets below freezing in the winter. It has to be a very long cold spell for that to happen. However, I did finish it off inside with working on cars in mind. I insulated the walls and the ceiling before drywalling and I have an insulated garage door.

Modern cars usually warm pretty quickly (when being driven) and if you have heated seats, to me, it's no big deal to get into a car with leather seats in the winter that has been in my garage.
 

Midwayman

Diamond Member
Jan 28, 2000
5,723
325
126
I have CO detectors already yeah

you usually have to hit the button twice to get Remote Start to work, in quick succession. they probably had an aftermarket if it didn't have a cut off I would guess.

no idea how people keep keys in their back pockets tho :p



not as nice as remote start, ie cant plug in at work in the winter ETC ETC

Well, my dog jumping around on the couch has managed to buy things with my wife's ipad off amazon. It also frequently changes Tv channels. Just saying....