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Sealed combustion Combi....

kcopp Member Posts: 4,188
I was asked to look at a small "cottage" today that has no basement, just a crawlspace. The place has a boiler and water heater that are natural draft and are both located in a bedroom.... crazy stuff.
By going to a combi unit that is sealed combustion does that make it acceptable to keep them in a bedroom?


  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    I would think so. I just did a Navien in the same situation, no issues with inspection.
  • j a_2
    j a_2 Member Posts: 1,801
    To ensure adequate venting and ventilation, follow these guidelines:
    ● Maintain proper clearances from any openings in the building. ● Install the boiler with a minimum clearance of 12 in (300 mm)
    above an exterior grade or as required by local codes.
    ● Maintain a minimum clearance of 4 ft (1.2 m) from heating and cooling vents.
    ● Do not enclose the vent termination.
    ● Install the exhaust vent in an area that is free from any
    obstructions, where the exhaust will not accumulate.
    ● Do not install the boiler where moisture from the exhaust may discolor or damage walls.
    ● Do not install the boiler in bathrooms, bedrooms, or any other occupied rooms that are normally kept closed or not adequately ventilated.
  • Ironman
    Ironman Member Posts: 7,119
    Check with your code official. Here in VA, one code allows it, the other doesn't. It depends which code the house was built under.
    I know that's pretty dumb for a state that usualy has some common sense laws, but that's the way it is.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    Build a wall around it with a door, now it is not in a bedroom.
    Harvey Ramer
  • kcopp
    kcopp Member Posts: 4,188
    House was built in 1982... long before any licensing here in NH. I was called for a gas leak outside on a leaking coupling. Yes, it a shipping/ merchant coupling (duh). I have warned the HO that if the inspector goes inside it could really hit the fan. She wants to sell this place in the spring. I'm trying to get a game plan together if it goes south quick.
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    Wow, wonder how long it was leaking and was it blown up from the initial tightening?
  • kcopp
    kcopp Member Posts: 4,188
    The tenant said he has smelled gas for the 5 years he has been living there.
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    :) gas bill high?
  • Jack
    Jack Member Posts: 1,046
    kcopp said:

    House was built in 1982... long before any licensing here in NH."

    I can't resist, and don't mean to understate the point, but "Live Free or Die!" Spooky, the things you run across

  • kcopp
    kcopp Member Posts: 4,188
    Hopefully it keeps me employed!
  • JStar
    JStar Member Posts: 2,752
    Build an outdoor/attached shed?
  • NYplumber
    NYplumber Member Posts: 503
    Should work so long that code dictates it is safe.
    I saw a navian installed in a bathroom above the toilet with the piping in the bedroom closet right behind the unit. Maybe dress it up with photos like the LC ductless split.
  • icesailor
    icesailor Member Posts: 7,265
    I guess I understood wrong.

    When did it become OK to install fossil fueled appliances in bedrooms? Is there now a specific code exemption for direct vented appliances in bedrooms?
  • delta T
    delta T Member Posts: 883
    I'm in Colorado so my local codes may vary, but as far as I know it is a big no no. I'm with Ice on this one, I have not heard of any exception to the rule for sealed combustion. No CO producing appliance in a bedroom. Period. Maybe your local code is different...but even code aside I would not want the liability. You never know what will go wrong. Heard way too many horror stories...seen a few myself.
  • gennady
    gennady Member Posts: 839
    In NYC there is no way even mod con boiler installed in bedroom will be accepted. Even in another room with door into bedroom.
  • kcopp
    kcopp Member Posts: 4,188
    I can see this now...I'm going to be the bad guy for bringing this up to the HO and prob the building official. Either I am liable or I am going to cost the HO a lot of money.
    No good deed goes unpunished. :#
  • icesailor
    icesailor Member Posts: 7,265
    Why are you the bad guy? You didn't make the rules. You just have to abide by them.

    People died before that rule went into place. 20 or 30 years ago, during some energy crisis, some Einstein came up with an improved kerosene room heater. One that didn't stink (much) and didn't give off CO. Or so the manufacturer said.

    No matter what they said, you still couldn't legally use them in a bedroom.

    Maybe they don't give off CO (doubtful). But they will still suck all the oxygen from a room and you can dream about an imaginary aircraft ride down to Jamaica while sleeping. Like that couple in the Turbo single going from Rochester, NY to Florida. They fell before they hit the NY boarder and never woke up.

    Its not your fault. I got really tired of "contractors" explaining to me why my code was wrong and I should just do what the GC wanted anyway.

  • 4Johnpipe
    4Johnpipe Member Posts: 479
    Kcopp...you wont be the bad guy at all. Check for code compliance and inform them . In NJ as long as the appliance clearance ratings are met and the boiler manufacturer does not prohibit it. You can install power direct vented appliances in sleeping areas. It must draw combustion air form the exterior.
    Considerate People, Considerate Service, Consider It Done!
    email: [email protected]
  • Tim McElwain
    Tim McElwain Member Posts: 4,588
    edited October 2014
    Here is what NFPA 54 National Fuel Gas says:

    10.1.2* Installation in a Bedroom or Bathroom.
    Appliances shall not be installed so their combustion, ventilation, and dilution air are obtained only from a bedroom or bathroom unless the bedroom or bathroom has the required volume
    in accordance with 9.3.2. . A.I0.1.2 Also see prohibited installations in 10.6.1, 10.7.1, 10.8.2, 10.9.2, and 10.23.1. The requirement in 10.1.2 was added to the' 1984 edition after considerable discussion on whether gas-fired appliances should be allowed to be installed in bedrooms and bathrooms. Originally, the code prohibited most gas appliances in bedrooms or bathrooms, and in closets
    or small spaces having access only through a bedroom or bathroom, for the following reasons:

    1. Such rooms are usually kept closed, are small in size, and may not provide adequate air for combustion, draft hood dilution, and ventilation.
    2. This prohibition was consistent with other codes.
    3. There is an increased possibility of moisture and lint accumulation within the appliance in such rooms.
    4. The potential for contact with hot surfaces and for ignition of fabric is increased in small rooms.
    5. Proper ventilation for the products of combustion can be lacking in small rooms.
    6. Hair spray and other aerosol products that can accelerate corrosion of the equipment are likely to be present in bedrooms and bathrooms. (Note: Hair spray is no longer a prob-
    lem since the propellant has been changed.)

    The requirement was revised in the 1988 edition of the code to provide a more positive statement on small spaces. The revised requirement permitted the installation of direct vent appliances (which do not draw air from the room) in bedrooms and bathrooms, and to provide for access to furnace closets (which can draw outside air for combustion and ventilation) located in or having access through bedrooms.

    Bedrooms and bathrooms almost always have doors. Therefore, appliances that take air for combustion and ventilation from the room in which they are installed must not be installed in these rooms, with the exception of certain low-input heating appliances covered in 10.23.1.

    Paragraph A.I 0.1.2 draws attention to other paragraphs having specific prohibitions on the installation of appliances in bedrooms and bathrooms under certain conditions. Prohibited installations for the appliances indicated are covered in the following subsections:
    Decorative appliances for installation in vented fireplaces (see 10.6.1)
    Vented gas fireplaces (see 10.7.1)
    Non-recirculating direct gas-fired industrial air heaters (see 10.8.2)
    Recirculating direct gas-fired industrial air heaters (see 10.9.2)
    Room heaters (see 10.23.1)
    Most of these prohibitions exempt rooms or spaces in which air for combustion and ventilation meets the volume requirements of 9.3.2.

    In 1994, the code was revised to permit the installation of listed, wall-mounted room heaters with limited input ratings and oxygen depletion safety shutoff systems in bedrooms and bathrooms that meet the requirements of Section 10.23, and where these heaters are acceptable to the authority having jurisdiction. Small space heaters are the normal means of heating homes in warmer parts of the United States, especially in the Southeast. The. 1994 re-
    vision permitted older, open flame heaters to be replaced with newer, safer appliances by allowing them to be installed where permitted by the authority having jurisdiction. Since then,
    many states have reversed their position of prohibiting such appliances.

    10.1.3 Room Size in Comparison Calculation.
    Where the room size in comparison with the size of the appliance is to be calculated, the total volume of the appliance is determined from exterior dimensions and is to include fan compartments and burner vestibules, where used. Where the actual ceiling height of a room is greater than 8 ft (2.4 m), the volume of the room is figured on the basis of a ceiling height of
    8 ft (2.4 m).

    Subsection 10.1.3 contains an important requirement concerning the life of appliances. Appliances installed in small spaces can heat the space with the waste heat generated by the appliance. High temperature can lead to reduced life of electric motors due to lubrication failure and can shorten the life of electrical and electronic components. The important concept of room size in comparison with appliance size is discussed further in the commentary following 10.2.3(1).
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    I'm reading the combustion air requirements. Therefore, a sealed combustion unit, with direct vent and sealed intake combustion air from outdoors is permissible.

    Unless I'm misinterpreting.
  • kcopp
    kcopp Member Posts: 4,188
    That is exactly why I have been on here for so many years. I do appreciate everyone's input...always. Even if it stings. ty.
    Bob Bona_4
  • BobC
    BobC Member Posts: 5,401
    I had a a Smith G8-3 with a EZ-Gas installed a couple of years ago. After they installed it I installed a combo CO / gas detector just to be on the safe side. This is a 100 year old balloon framed house so I'm sure there is beau coup air available, but I thought back to other places I had lived.

    In the late 60's I was in the army down in Ft Benning, I was quartered in an old Frame building that was put up before WWII. I was permanent CQ for this building along with 3 other guys, we all had day assignments and did the CQ after hours to issue and accept equipment from field problems for the infantry OCS school. Our barracks room was about 12 x 20ft and the heat source was an open gas log. The same type of heat source was used for the office and the maintenance bays. There was probably enough infiltration in that old building so it was probably ok as far as CO is concerned.

    In Korea I was on a very remote mountaintop microwave site (26 miles from any command authority) and the buildings were Quonset huts. In the winter it got down to -40 with wind that really did blow the feathers off your crowbar. The heat source were diesel barrel stoves (vented through the roof) with 5 gallon jerry cans hung on the side. 20X40 ft steel hut (2 stoves per hut- pretty tight as far as infiltration went) I'll bet the CO was questionable at best because they had now windows and the old doors were pretty tight.

    By the way if your going to be in the army, being 26 miles from the nearest officer is the only way to go - especially if your in charge of the site!

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge