QUESTIONS & ANSWERS from "Ask-the-Wizard":

ANSWER FROM HOME-WIZARD.COM:

Alice:

PLEASE NOTE: water in a hot water system can be scalding hot. You need to be very careful working around your hot water system to keep yourself from being burned. If you are un-sure what you are doing, you should contact a trained professional.

Newer hot water systems typically have a diaphragm-type expansion tank, which is sealed, so it's not necessary to drain it. However, from time to time, these types of tanks need the air inside them pressured up. Older hot water systems typically have conventional expansion tanks that should be flushed out annually. You can recognize a conventional expansion tank because they will have two valves around them: a shutoff valve going to the furnace; and a drain valve on the bottom of the tank.

Here is the procedure for draining a conventional type expansion tank. First, close the shutoff valve that goes to the furnace. Position a bucket under the drain valve on the bottom of the tank. If you cannot position a bucket underneath the drain, then you can attach a garden hose to the drain, and run the other end of the hose to a bucket. Once the bucket is in place, then open the drain valve. The water should flow out, but if it doesn't, it may be necessary to use a wrench to open the vacuum-breaker plug (not all tanks have this plug) on the drain valve. After the tank has been drained, close the drain valve and vacuum-breaker plug; then re-open the shutoff valve going to the furnace.

Once again, if you have any concerns about doing this procedure safely, you should contact a professional heating contractor.

Hope this is helpful.

Regards,
Home-Wizard.com
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QUESTION from "Bobby": 

Why has my gas boiler started to blow back?

ANSWER FROM HOME-WIZARD.COM:

Bobby:

If your gas boiler has started to blow back, you should have it inspected by a trained professional RIGHT AWAY. The problem could be due to items such as a bad burner, blocked exhaust piping, etc. But you should have a trained service technician do a thorough inspection.

In the meantime, you need to be very careful of poisonous carbon monoxide gas that could be created from incomplete combustion or leaking exhaust gas. Make sure that your carbon monoxide detectors in your house are working properly, and that your boiler area is well ventilated until you can get a service person to inspect your boiler. Which you should do as soon as possible.


Hope this is helpful.
Home-Wizard.com
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QUESTION from "perkybob": 

Why my electric furnace makes noise when it is turned off.  Could it be a stuck or noisy relay or what?

ANSWER FROM HOME-WIZARD.COM:

Dear perkybob:

What type of noise is it?

Does it sound like "creaking metal"? Or a motor turning? Or is it a "whooshing" sound?

Or how would you describe the sound that you are hearing after your furnace turns off?

Regards,
Home-Wizard.com
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QUESTION from "Kenneth": 

I notice that my low water light will come on sometimes and my furnace will not heat up the house even though the water level show sufficient amount of water. But when I flush out the water and reestablish the water level the furnace will kick in and the baseboards will began to heat up again. It does not happen often but sometime I have to flush water out more than usually when the water light come on I would like to note that I do not have an auto feed and that every once in a while I would have to fill and flush water out of the furnace. Could this be from a build up of rust in the pipes that cause the low water indicator to come on and shut the furnace? If so can this be clean out other then continuing to draining and flush water out of the furnace ?What do you think is causing this to happen. Your information is greatly appreciated.

ANSWER FROM HOME-WIZARD.COM:

Dear Kenneth:

Yes, your problem with the your furnace shutting down could be caused by rust and sediment affecting your low water level cut-off gauge.

If the boiler and the low water cut-off gauge are not flushed of sediment, the low water cutoff could hang up on the sediment. You should follow the appropriate procedure for your particular furnace system to drain and flush your boiler. And as part of your annual inspection and service, a trained service technician should take the low water cutoff apart to manually scrape and clean the walls of it, and to also clean the sight glass.

Hope this is helpful.
Home-Wizard.com
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FOLLOW-UP COMMENT from "Kenneth":  

Dear Home-Wizard,
The explanation you gave me for my furnace yesterday is right on point the sediment in the glass and water level gauge is just as you describe. I will have a technician come to clean it out.
Thank you very much.
Kenneth

ANSWER FROM HOME-WIZARD.COM:

Dear Kenneth:

Thanks for the feedback!

Glad that we could help you with this.

If you have other home maintenance questions come up, just let us know.

Regards,
Home-Wizard.com
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QUESTION from joew on 3/31/2008:

My boiler (steam heat) is always getting too much water causing radiators to overflow.I fill per sight glass,could water feed valve be faulty .

ANSWER FROM HOME-WIZARD.COM ON 3/31/2008:

Dear joew:

Have you tried testing the pressure and operation of your auto-feed valve?

Home-Wizard.com
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FOLLOW-UP COMMENT from joew on 3/31/2008:

My boiler (steam heat) is always getting too much water causing radiators to overflow.I fill per sight glass,could water feed valve be faulty .

FOLLOW-UP COMMENT from joew on 3/31/2008:

The boiler is not fed with a auto fill,I manually have to feed it to proper level.Then it gradually overflows radiators.Would a new shut off solve the problem? I cant think of any other way the boiler is getting water .THANKS

ANSWER FROM HOME-WIZARD.COM ON 3/31/2008:

Dear joew:

Before you replace your make-up water valve, one other thing to check is your expansion tank on your system.

When a hot water heating system heats up, the water in the system expands, and since it is a closed system, this expanded volume of water has to go somewhere. This is why hot water radiator heating systems have an “expansion tank” that accommodates this additional water volume. If there is a problem with your expansion tank, the water possibly has nowhere to go except out your radiator.

So you might want to check your expansion tank before you replace your water make-up valve. And remember, the water in your system is VERY HOT, so please be careful.

Hope this is helpful.
Home-Wizard.com
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FOLLOW-UP COMMENT from joew on 3/31/2008:

I have steam heat.Is there an expansion tank?Thanks again.Joe W

ANSWER FROM HOME-WIZARD.COM ON 3/31/2008:

Dear JoeW:

Here's a link to an article on how to troubleshoot an expansion tank in a steam heating system:

http://home.howstuffworks.com/how-to-troubleshoot-a-hot-water-and-steam-distribution-system1.htm

Hope this is helpful.
Home-Wizard.com
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QUESTION from Seattle house owner on 3/27/2008:

Our furnace backed up/got clogged while we were out, and when we returned, there was soot and smoke EVERYWHERE. We shut off the furnace, and a professional will come fix the problem, but what do we do meanwhile to help clean out the house? We will have carpet cleaners and maids come out, but is the residue toxic or carcinogenic?

ANSWER FROM HOME-WIZARD.COM ON 3/27/2008:

Dear "Seattle house owner":

Sorry to hear about your furnance problem. What a mess.

Regarding your question about the toxicity of the soot that is now throughout your house, unfortunately, this is beyond our expertise.

However, what I might suggest is that you contact your insurance company and ask them for a recommendation for a list of specialists in this area (typically their policies are not to recommend any one in particular, but they should have a list of preferred professionals). A home insurance company of course deals with this kind of problem all of the time, and I personally had a similar situation to yours, and found my insurance company to be very helpful in finding an expert.

Hope this is helpful.
Home-Wizard.com
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QUESTION from Donna Croswell on 5/11/2008:

My mother-in-law has been turning her oil furnace off and on a couple of times a day in order to save on her oil bill. Should she be doing this? Her furnace is at least 30 years old.

ANSWER FROM HOME-WIZARD.COM ON 5/12/2008:

Dear Donna:

No, I would not recommend that your mother-in-law turn her furnace off and on several times a day in an attempt to say energy.

Assuming that her house is thermostatically controlled, then the thermostat (or thermostats if she has more than one) will turn the furnace on and off as needed to keep her house at her desired temperature, that is, the temperature where she has set her thermostats. As such, there is no reason for her to manually shut down the furnace.

If her interest is in lowering her energy bill, I would suggest that she looks at the Energy Saving Tips in the online Maintenance Library of Home-Wizard.com: 

http://www.home-wizard.com/maintenance/energysavingstips.asp

In addition, I would suggest that she also looks at Energy Savings section of Home-Wizard.com:

http://www.home-wizard.com/EnergySavings.asp, 

which will show the routine maintenance tasks that will help her save energy for her particular home.

Hope this is helpful.
Home-Wizard.com
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QUESTION from jim t cuff on 5/20/2008
I have an oil-fired furnace/with hot water baseboard for my ranch house. I am quite handy, and would like to vaccume out the soot from the inner furnace. is their any special type vaccume/shop-vac i need to use and bag. thanks jim
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ANSWER FROM HOME-WIZARD.COM on 5/20/2008
Dear Jim:

For difficult jobs where you need strong suction, like vacuuming out a sooted up oil burning furnace, I would suggest that you look at the "Sootmaster" furnace vacuum:

http://www.cgfproducts.com/prod5frame.htm#01

I've heard some good things about the DeWalt DC500 vacuum:
http://www.dewalt.com/us/products/tool_detail.asp?productID=6220

But I've heard many complaints about the Stinger brand vaccum.

Hope this is helpful.
Home-Wizard.com
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QUESTION from jim t cuff on 5/20/2008

I have a regular 3 gallon sears wet/dry vac could i use that? thanks

jim
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ANSWER FROM HOME-WIZARD.COM on 5/20/2008
Jim:

The main concern that I would have with using a small Craftsman wet/dry vacuum for vacuuming out soot from a oil-fired furnace is that the filter system may not be fine enough to keep the soot from coming through and making a mess in your house. I've heard of cases where the tiny soot particles got churned up in the air and actually setting off the fire detectors in the home.

Part of the reason that the bigger (and unfortunately more expensive) furnace vaccums have more suction power, is so they can force the air through the finer filtering system.

Hope this is helpful.
Home-Wizard.com
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FOLLOW-UP COMMENT from jim t cuff on 5/21/2008
Great, thanks for your help. jim
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QUESTION from jesse on 9/2/2008
I want to disconnect my existing cast iron boiler in order to move it 12 inches or so and then reconnect. I have baseboard style heaters but they appear not to have bleeder valves on them in order to drain the system down. What would be the best way to ensure the entire system is drained down. I also have a system when installed that has no shut-off or service valves to isolate the piping to the baseboar heaters , only the boiler drain at the floor level and a boiler drain right where the piping attaches to the supply side. Any ideas would be apprecited

ANSWER FROM HOME-WIZARD.COM on 9/3/2008
Dear Jesse:

Actually, baseboard heating systems do not usually have bleeders on the baseboard heating pipes. But at your boiler, there should be purge valves. So after you shut off your boiler and you close your water supply valve, you should be able to drain your system by opening up the other valves around your boiler.

Hope this is helpful.
Home-Wizard.com 
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QUESTION from Joel in NY on 10/7/2008
Just in the last year, my gas-fired hot water baseboard system (2-zone) has had a problem. Whenever the heat goes on in the morning, the pressure builds slowly over norm until the relief valve starts dripping. I can open the drain valve on the expansion tank to let out some water (it runs clear). This helps in the short run, but I have to do this every day. Once I tried draining the expansion tank completely, but the refill valve just kept filling up the system. Can you suggest what the problem might be and how to resolve it? Water temp is set to 140-160 F. Many thanks!

ANSWER FROM HOME-WIZARD.COM on 10/7/2008
Dear Joel:

A leaking pressure relief valve for your hot water baseboard heating system is unsafe. It either means that your pressure relief valve has failed, or there is an over-pressure situation in your system.

If it is because your pressure relief valve is failing, then the valve absolutely should be replaced. This is a very, very important safety feature for your system. And if it is leaking because of an over-pressure situation in your system, then this needs to be address as soon as possible.

Here is a webpage that describes more about dripping pressure relief valves: http://www.inspect-ny.com/heat/ReliefValves.htm

Hope this is helpful.
Home-Wizard.com
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QUESTION from BK on 10/18/2008
I just moved into a house with a baseboard heating system. I had a plumber come check out the system, but the gas wasn't on. He said to have the gas company light the pilot when they turned on the gas. He said everything was good to go after that. The serviceman with the gas company lit the pilot, but said he didn't notice a pressure relief valve. It just has a cap. He said not to run it until we got a relief valve and then told me some of the things that could happen. Do I need the relief valve or is the cap good enough? I think I know the answer, I just want to be sure.

ANSWER FROM HOME-WIZARD.COM on 10/18/2008
Dear BK:

Yes, your intuition I suspect is correct. I would NEVER recommend operating a hot water boiler system without a pressure relief valve. And further, even if a system has a pressure relief valve, it needs to be routinely inspected and tested to ensure that it is operating properly. This is a VERY important safety feature of your home.

Hope this is helpful.
Home-Wizard.com
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QUESTION from Stephanie on 10/20/2008
Just bought a 100 year old house. My main question has to do with turning on and off the system during this cold than mild days of Oct. I grew up with electric heat and this is what we did, but I'm thinking that turning on an off this system isn't the way to go. Also, with electric heat you try and keep the house always at the same temp so you don't play with the programing much, is this true of steam heat or is it better to program variable temps throughout the day (depending when we'll be home).

ANSWER FROM HOME-WIZARD.COM on 10/21/2008
Dear Stephanie:

Regarding the first part of your question, if you are wondering if during what's called the "shoulder months" when your heating demand for your house is relatively low and may fluctuate significantly, whether you should be turning your heating system off and on . . . then the answer is that it depends on the kind of heating system that you have and how it is setup to operate.

It sounds like you have a hot water boiler which I assume provides hot water to either room radiators or baseboard heaters. If you system is setup to circulate water only when a wall thermostat tells the system that the temperature is too low, which both turns on your furnace boiler to heat water and a pump to circulate this water, then it is fine to turn your system on and off. However, assuming that your thermostat is operating properly, then there is no reason to have to turn your system on and off, since the wall thermostat will do it for you. On the other hand, if in your 100 year-old house you have a system which for some reason is not thermostatically controlled, then you would need to turn the system on and off.

Regarding the second part of your question, depending on the cost of electricity in your region of the country, and cost of the type of programmable thermostat that you would need to purchase . . . yes, it can make good sense to have a programmable thermostat automatically adjusting the room temperature for you. For example, if you are gone during the day, you could have your programmable thermostat setup so that it keeps your house at lower temperature during the day, but it turns the heat up at a time that will allow your home to be at a comfortable temperature by the time that you get home. And similarly, you can have it turn down the heat a little bit while you are sleeping, then come up to a higher temperature for around the time that you will be getting up in the morning. Even dialing down a few degrees over the entire heating system can help save you money.

Hope this is helpful.
Home-Wizard.com
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QUESTION from Graham on 10/31/2008
Hi

We have 3 radiators upstairs (one of which is a towel dryer in bathroom) and 2 radiators upstairs. I have bled all the radiators as we are now looking to use the heating regularly. Last time i used the system about a month ago, all was well but now when the heating is turned on there is a relatively high pitched pulsating sound that you can hear anywhere in the house...after about 45 minutes of the heating being on this sound stops.

The system has been on for about an hour now and I can hear the gentle flow of water in the upstairs radiator in my bedroom, I cannot hear a similar sound from the other radiator in my back bedroom (and this one seems hotter).

I think we have a gravity system with a tank of water upstairs (brown water so I assume this is the radiator water?)

What do you think could be causing the relative high pitched pulsating sound? 

Many Thanks
Graham

ANSWER FROM HOME-WIZARD.COM on 10/31/2008
Dear Graham:

From what you described in your hot water radiator system and the high-pitched sound that you are hearing when the heat initially comes on, I would suggest that you first check to see if the expansion tank on your system has failed.

Hope this is helpful.
Home-Wizard.com
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QUESTION from Bill on 7/6/2008
I am building new walls in my basement and the pipes from my hot water baseboard pipes are coming straight down and i need to put an elbow on the pipe how do i drain and refill and purge the hotwater system thank you

ANSWER FROM HOME-WIZARD.COM on 7/6/2008
Dear Bill:

Regarding your question of how to drain and refill and purge the hotwater system for your baseboard heating system, first, to drain your system, shut off your boiler and make a note of the water pressure. Next locate the self-feeding (auto-makeup) water valve and ensure that your make-up water supply is shutoff. Next, attach a garden hose to one of the spigots coming off of the return line that goes back to your boiler, and run the other end of the hose to either a drain or to outside. Then open up all of you valves that go to your various heating zones. Then open up the spigot and let the water drain out through the garden hose. If your boiler has been running, then BE CAREFUL that the water can be scalding hot.

To refill and purge the air from your system, ensure that the make-up water supply is connected and water supply valve is open. Close them all, and then one at a time, open the valve to each heating zone of your house. Then while manually opening the auto-makeup valve, keep the spigot open and let the water run out the garden hose to your drain our outside. Let it run until you no longer see any air bubbles. While you are doing this, keep an eye on the water pressure and don't let it get above 25 PSI. If needed to control the pressure, release the auto-makeup valve momentarily. After you have stopped seeing air bubbles, release the auto makeup valve and close spigot. Allow the water pressure to return to normal. You then repeat these steps until all of your zones have been bled. When done, put your zone valve to their operating positions. Then check the water pressure, which should be the same as what you noted at the beginning. And then finally, turn your boiler back on.

Hope this is helpful.
Home-Wizard.com
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QUESTION from Hoping to Save Money in PA on 7/9/2008
I have hot water baseboards that run off of an oil furnace (which also supplies the hot water to the rest of the house). I am thinking about replacing the oil furnace with an electric heater, but I want to make sure I get a big enough unit. How much water (GPM) is typically circulated through the baseboards?

ANSWER FROM HOME-WIZARD.COM on 7/10/2008
Dear "Hoping to Save Money in PA":

The short answer to your question of how much water is circulated (GPM) through your baseboard heating system, is that it depends on the size of your circulation pump and the size (diameter) and length of the piping in your system.

Here is a link to a great guide by Bell & Gossett on how to size a baseboard heating system. Hopefully it will have what you need. If not, just let us know, and we'll try to find something else for you.

Regards,
Home-Wizard.com
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QUESTION from Donna Croswell on 5/11/2008
My mother-in-law has been turning her oil furnace off and on a couple of times a day in order to save on her oil bill. Should she be doing this? Her furnace is at least 30 years old.
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ANSWER from Home-Wizard.com on 5/12/2008
Dear Donna:

No, I would not recommend that your mother-in-law turn her furnace off and on several times a day in an attempt to say energy.

Assuming that her house is thermostatically controlled, then the thermostat (or thermostats if she has more than one) will turn the furnace on and off as needed to keep her house at her desired temperature, that is, the temperature where she has set her thermostats. As such, there is no reason for her to manually shut down the furnace.

If her interest is in lowering her energy bill, I would suggest that she looks at the Energy Saving Tips in the online Maintenance Library of Home-Wizard.com: 

http://www.home-wizard.com/maintenance/energysavingstips.asp

In addition, I would suggest that she also looks at Energy Savings section of Home-Wizard.com:

http://www.home-wizard.com/EnergySavings.asp, 

which will show the routine maintenance tasks that will help her save energy for her particular home.

Hope this is helpful.
Home-Wizard.com
____________________

QUESTION from Dave on 10/6/2008
I have a Bryant, three zone, Gas Boiler Furnace.
It turned on when the weather was warm and the thermastats where turned off. The only why I can stop it is to turn off the electrical beaker switch. What is causing the furnace to not read the thermastat? Is this something that I can troubleshoot and replace myself?

ANSWER FROM HOME-WIZARD.COM on 10/6/2008
Dave:

If your thermostat for your furnace is not working properly, yes, there are a number of things that you can check to diagnose the cause. Here is a webpage that describes some general troubleshooting techniques for a problem thermostat:

http://www.happynews.com/living/homerepair/troubleshooting-common-thermostat.htm

Hope this is helpful.
Home-Wizard.com
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QUESTION from kmpeters on 11/1/2008
The attic addition to my home was added 12 years ago. And I believe added to the existing heating system. I have a boiler with radiators in the main level. In the addition there are radiator baseboards, with a separate theromostat. I have bled the air out of the lines but still do not get any heat from any of the units in the addition. They are not ice cold but are far from warm. Would there have been a separate controller added when this addition was done in order to tie the existing heating unit to it? We are replacing the therostat to see if that makes a difference.

ANSWER FROM HOME-WIZARD.COM on 11/1/2008
Dear kmpeters:

If you have properly bled your upstairs radiators, and they are still not heating up enough, then your problem could be that your heating system's expansion tank is empty. You would need to check the ball valve in the tank and fill the tank enough to get the ball to float when the system is cool.

If this is not the problem (or if there are other symptoms that you didn't mention in your email), then here is a webpage that describes solutions for different kinds of radiator problem situations:

http://www.diynot.com/pages/pl/pl033.php

Hope this is helpful.
Home-Wizard.com
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QUESTION from linda on 11/9/2008
I moved into my home a year a go and the room that stores the laundry room, boiler furnance and hot water tank are all in the same room in the basement. There use to be a door to this room and it was removed. I would like to replace the door but I donot know if it was removed beacuse of ventilation issues. My question is, if I put a nother door up should it be a door that has vents or should I just leave the door off? There are no windows in this room.

ANSWER FROM HOME-WIZARD.COM on 11/9/2008
Dear Linda:

You should check with the building inspector for the town that you live in for the specific regulations for your particular town. But I suspect that you will find that a room that contains a boiler in it will need to have a door to close it off from the rest of the house.

And yes, assuming your furnace is burning oil, propane, natural gas, etc., then it needs to "breathe", that is, it needs to have adequate supply of air (oxygen) coming into the area.

Some homes have what is called a "fan-in-a-can", which when the furnace turns on, it brings in air from outside your home. This is much more efficient than bringing air from inside your house, since air from the outside is not air conditioned or heated.

Hope this is helpful.
Home-Wizard.com
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QUESTION from phil baker on 11/13/2008
I have a boiler, approx 10 yrs old, in our new home's basement. I've never even heard of one! The radiators in the house all get nice and warm and look majestic. What do I need to do to the boiler? There are controls on it that I don't recognize.

ANSWER FROM HOME-WIZARD.COM on 11/13/2008
Dear Phil:

The most important thing you can do for your hot water heating system's boiler is having a trained service technician do an inspection and maintenance servicing of it once a year. Other than that, you should ordinarily not need to make adjustments during its normal operation.

Having this annual inspection and servicing done is VERY important, both from a safety standpoint and also for energy efficiency. The safety inspection includes checking the pressure relief valve and ensuring that your burner and exhaust ducting are both operating correctly.

The things that you should have your service technician do are shown on our furnace webpage of our online Maintenance Library at:

http://www.home-wizard.com/maintenance/furnace.asp

If you have any additional questions, just let us know.

Hope this is helpful.
Home-Wizard.com
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QUESTION from Stephanie on 10/20/2008
Just bought a 100 year old house. My main question has to do with turning on and off the system during this cold than mild days of Oct. I grew up with electric heat and this is what we did, but I'm thinking that turning on an off this system isn't the way to go. Also, with electric heat you try and keep the house always at the same temp so you don't play with the programing much, is this true of steam heat or is it better to program variable temps throughout the day (depending when we'll be home).

ANSWER FROM HOME-WIZARD.COM on 10/21/2008
Dear Stephanie:

Regarding the first part of your question, if you are wondering if during what's called the "shoulder months" when your heating demand for your house is relatively low and may fluctuate significantly, whether you should be turning your heating system off and on . . . then the answer is that it depends on the kind of heating system that you have and how it is setup to operate.

It sounds like you have a hot water boiler which I assume provides hot water to either room radiators or baseboard heaters. If you system is setup to circulate water only when a wall thermostat tells the system that the temperature is too low, which both turns on your furnace boiler to heat water and a pump to circulate this water, then it is fine to turn your system on and off. However, assuming that your thermostat is operating properly, then there is no reason to have to turn your system on and off, since the wall thermostat will do it for you. On the other hand, if in your 100 year-old house you have a system which for some reason is not thermostatically controlled, then you would need to turn the system on and off.

Regarding the second part of your question, depending on the cost of electricity in your region of the country, and cost of the type of programmable thermostat that you would need to purchase . . . yes, it can make good sense to have a programmable thermostat automatically adjusting the room temperature for you. For example, if you are gone during the day, you could have your programmable thermostat setup so that it keeps your house at lower temperature during the day, but it turns the heat up at a time that will allow your home to be at a comfortable temperature by the time that you get home. And similarly, you can have it turn down the heat a little bit while you are sleeping, then come up to a higher temperature for around the time that you will be getting up in the morning. Even dialing down a few degrees over the entire heating system can help save you money.

Hope this is helpful.
Home-Wizard.com
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QUESTION from Steve H on 12/12/2009
A couple of years ago my son put rocks down the furnace exhaust vent which vents to the outside at the back of our house. I am assuming it is venting properly since I feel air coming out. Do I have anything to worry about? Should I clear out the rocks?

ANSWER FROM HOME-WIZARD.COM on 12/13/2009
Dear Steve:

I would strongly suggest that you have the rocks removed from your furnace exhaust vent. Just because you can feel air coming out doesn't mean that you are getting the designed flow to ensure proper combustion in your furnace. It is not worth taking the risk of having dangerous exhaust gas backing up into your house, or having improper combustion risking deadly CO gas being produced.

Hope this is helpful.
Home-Wizard.com
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