Boiler room temperature

Alexnyu10

Hey folks, I wanted to ask some advice on managing my boiler room.

The boiler room is in the basement of my 3 story home, and it has a window that I can open that helps to control how much air from outside comes in.  I currently have it open slightly, and it leads to it being between 75-80 degrees Fahrenheit in the room even when the boiler is on. Is this a safe and ideal temperature, or would it be preferable to open to the window more and cool the room down closer to 70-75? (The only downside of opening the window more is that when it warms up slightly outside and the boiler isn’t turning on, the room can drop into the mid 60s if I forget to adjust the window shut). 

Room has CO2 and other safety features, just wanted to check if 75-80 degrees is a safe and ideal temperature for my natural gas steam boiler to operate efficiently in. 

pedmec

Room temperature is less important than making sure that you have proper air for combustion. Many boiler rooms that i have been in exceed the temperatures your dealing with by a lot with no issues.

Alexnyu10

Appreciate this. Is there any way to confirm the air is proper for combustion? Because the co2 alarm never has gone off and the boiler appears to be firing and heating great I assume that it is okay, but is there any way I can confirm this is the case? 

Long Beach Ed

Sufficient combustion air is very important, especially for gas fired equipment which produces excessive carbon monoxide when starved for air. The manufacturers literature will specify the minimum requirements which are based on BTU inputs of the appliances. Corrections must be made for any grills on the vents and for areas that don't communicate air with larger spaces. Insufficient combustion air can be very dangerous.

Since most home-style CO detectors do not signal low level exposure, which can be dangerous over a period of time, a combustion analysis using commercial type equipment and adjustment should be made regularly to assure the equipment is firing safely. Care must be taken that air is sufficient with different appliance combinations and different chimney conditions.

Alexnyu10

Thank you for this thorough explanation based on this I am going to open up that window to at least 70% open and see what that does to the temperature in the room but it seems like having more oxygen from outside coming in is only a good thing

Long Beach Ed

Since open windows are not considered a permanent assurance of proper air supply, codes require a better source of air in a confined boiler room. Remember that insufficient air supply can be the first step in a fatal carbon monoxide disaster with gas combustion.

You should really investigate this a bit further if those appliances don't draw their air source from a large area such as a basement.

Also consider that an open window in cold weather can allow a draft on water pipes which may result in freezing, bursting and flooding. Just all considerations we have to deal with, Alex.

Chris_L

Do you really want your basement to be 75-80 F? If not, I have to wonder if you have insulation on your steam pipes. With proper insulation, I doubt you'd need to open the windows in the basement of your home to achieve a comfortable temperature.

If you are concerned about CO, you should get a combustion test for the boiler, and have someone inspect the venting of the exhaust and the chimney.

hot_rod

A portion of your heat dollars are going out that open window. Check into proper combustion air admittance.

EBEBRATT-Ed

@Alexnyu10

The proper fix is to have the window taken out and replaced by a louver and automatic damper sized for the combustion air you need . The damper must be electrically interlocked with your heating equipment to open when it fires and close when it shuts down

ChrisJ

EBEBRATT-Ed said:

@Alexnyu10

The proper fix is to have the window taken out and replaced by a louver and automatic damper sized for the combustion air you need . The damper must be electrically interlocked with your heating equipment to open when it fires and close when it shuts down

What if no extra combustion air is required?
I don't think we know the details of the boiler room or anything else yet.

Alexnyu10

So I just checked the window and it actually is “louver damper” style window. It is not electric and I can only manually adjust it. The chimney also is working great, I have never smelled smoke or gas in the room, sometimes it just gets slightly warm if that louver window is closed. So right now I have the “damper louver” style window partially opened and it helps to keep the room closer to 70 instead of 80 if it’s closed.  I am happy to read this is the right style window, and sounds like in future I should invest  in an electric one that automatically opens and closes.  I

Alexnyu10

I honestly didn’t even realize the window was there for that intelligent reason and had never heard of louver damper windows, but googling pictures now and that’s exactly what the window is, it’s also great because it doesn’t let any water in when it rains. 

Alexnyu10

Can someone ELI5 how this style of window uniquely works and makes sense in a boiler room? No rush and appreciate the wisdom of this group so much. Also if it is manually adjusted/opened, what is the best way to adjust it? 

Long Beach Ed

How big is this boiler room? If your room needs external combustion air you are putting dollars before your family's lives. You are playing games with boiler room temperature and window louvers, I suppose because you don't want to spend the money to determine the safe course.

As Chris mentioned, only by analyzing the combustion air requirements can this system operate safely.

Alexnyu10

Just checked the blue print and it’s 7 1/2’ x 7’

Long Beach Ed

You must confirm the combustion air requirements for this system operate safely.

The manufacturers literature will specify the minimum requirements which are based on BTU inputs of the appliances. Corrections must be made for any grills on the vents and for areas that don't communicate air with larger spaces. This requires the ability to read and calculate. There is no shortcut.

Operation of gas appliances with insufficient combustion air can be very dangerous.

hot_rod

Fan in a Can option? I never used one, seems like a good match, being a listed device.

EdTheHeaterMan

I forgot to his "Post Comment" yesterday

This is a form to use to figure out if you have sufficient combustion air from within the building or if you have what is considered a "confined space" meaning you do not have sufficient combustion air from within the home or building.
https://www.hillsborough-nj.org/government/documents/department-documents/construction/23-combustion-air-calculation-sheet-with-instructions/file

Alexnyu10

EdTheHeaterMan said:

I forgot to his "Post Comment" yesterday This is a form to use to figure out if you have sufficient combustion air from within the building or if you have what is considered a "confined space" meaning you do not have sufficient combustion air from within the home or building. https://www.hillsborough-nj.org/government/documents/department-documents/construction/23-combustion-air-calculation-sheet-with-instructions/file

This is incredibly helpful!!!

Alexnyu10

Just found this in the manual for the boiler, it’s a slant fin GXHA-100. It definitely is installed with the necessary clearances, and the window appears to be perfectly sized for the required square inches. Also I had a licensed plumber install the boiler brand new in august 2021 and tune it up and safety check in 2022, I just never asked for instructions on the window. It seems like the room temperature can go up to 100 based on the manual (the hottest I’ve ever seen it in there is 80$ I am still going to aim to open the window enough to keep it in 70s

“BOILER ROOM AIR SUPPLY AND VENTILATION

An ample supply of air is required to obtain combustion and ventilation. Room temperature over 100°F may cause nuisance tripping of the Blocked Vent Safety Switch.

ALL AIR MUST COME FROM OUTSIDE, directly through wall openings to the boiler or through unsealed openings around windows, doors, etc. in the whole building. When buildings are insulated, caulked and weather-stripped, now or later on, direct opening to outside may be required and should be provided. If the boiler is not on an outside wall, air may be ducted to it from outside wall openings.

 The National Fuel Gas Code, ANSI Z223.1-latest edition speci- fies openings for air under various conditions. Local codes may specify minimum opening sizes and locations. The following recommendation applies to buildings of energy-saving construc- tion, fully caulked and weather-stripped:

Provide one GRILLED opening near the floor and one near the ceiling on an outside wall near the boiler (or duct from such openings to the boiler), EACH opening to be a minimum of one square inch per 2000 Btuh input to ALL APPLIANCES in the area. For a total appliance input of 200,000 Btuh, each open- ing will be 100 square inches. A grilled opening 10" x 10" has 100 square inches of area. If fly screen must be used over openings, double the area and inspect and clean the screen frequently.

Openings must NEVER be reduced or closed. If doors or win- dows are used for air supply, they must be locked open. Protect against closure of openings by snow and debris. Inspect frequently.

NO MECHANICAL DRAFT EXHAUST OR SUPPLY FANS ARE TO BE USED IN OR NEAR THE BOILER AREA.

The flow of combustion and ventilating air to the boiler must NOT be obstructed.“

Long Beach Ed

So if the window is the top opening, what is the bottom?

Alexnyu10

Long Beach Ed said:

So if the window is the top opening, what is the bottom?

So it looks like both the bottom of the door to the boiler room (the rest of the basement is pretty large), and it’s hard to describe but along the wall in the boiler room floor, the wall is not finished or insulated, and you can feel cold air from outside coming in, so I think both of those are helping and want to believe the plumber thought about it too. 

Long Beach Ed

Might be fine. Do the math and then check the chimney draft and draft over the fire. Check combustion and carbon monoxide under different conditions and you should be good.

EdTheHeaterMan

Long Beach Ed said:

So if the window is the top opening, what is the bottom?

There are several ways to accomplish this. If the boiler room is not considered a confined space, then no louver is needed. if the boiler room IS a confined space and the only outdoor opening is at the top pf the room, then a duct can be installed from a top opening to the floor. Look up NFPA 54 or The National Fuel Gas Code, ANSI Z223.1-latest edition for all kinds of ways to get the combustion air issue resolved.

It sounds like @Alexnyu10 does not have a confined space at this time and there is sufficient infiltration to provide sufficient combustion air.