Gas water heater in dryer compartment

[High Desert]

Can a natural draft gas water heater be installed in the same untility closet asa dryer?

I have a situation where they have installed a gas water heater with a natural draft vent in the same 27 sq. ft. utility closet as the washer/dryer. The question has come up whether the dryer exhaust will cause the gas vent to back draft into the space. I can't find a specific code section in the IRC that regulates this. Can soemone help?

 

[mtlogcabin]

I can tell you from experience YES it may back draft and extinquish the pilot light.

 

[mtlogcabin]

G2407.4 (304.4) Makeup air provisions.

Where exhaust fans, clothes dryers and kitchen ventilation systems interfere with the operation of appliances, makeup air shall be provided.

Find out the dryer exhuast CFM's and add that to what the water heater needs then make sure the proper amount is provided.

 

[High Desert]

Thanks mtlogcabin. I guess I need to determine whether it interferes with the operation of thewater heater venting.

G2407.4 (304.4) Makeup air provisions. Where exhaust fans,

clothes dryers and kitchen ventilation systems interfere with

the operation of appliances, makeup air shall be provided.

 

[mtlogcabin]

Some of Whirlpools installation instructions. Your post says the room is 27 sq ft that is pretty small for the dryer to work properly. My guess is the "B" vent will be the make up air for the dryer when it is working unless additional openings are provided.

Venting Requirements

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Venting systems for Whirlpool dryers must meet the following requirements:

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The capacity to handle 200 CFM of air for each dryer in the system.



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A back pressure of -1.0" (-25 mm) water column to 0.6" (15 mm) of water column when measured at the connection to the dryer.



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The minimum duct air velocity during normal operating conditions should be at least 1,100 FPM to keep lint moving in the air stream. (In a 4" diameter pipe, this requires at least 96 CFM.)

Back pressure should be measured with an empty dryer, a clean



Dryer Airflow

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The airflow of a dryer depends on the design of the exhaust vent. Each dryer model has a maximum rated vent length, shown in the product literature that is supplied with each model, or on the Whirlpool.com website. The exhaust airflow of any Whirlpool produced dryer at the maximum rated vent length is at least 100 CFM. The maximum airflow is 200 CFM. This includes standard vent and long vent dryer models.

Dryer Closet Installations

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Closets used for dryer installation must provide multiple openings to allow air to flow through the dryer and around the dryer to dissipate heat. Refer to the product literature for details of room venting requirements. Any dryer enclosure or room that does not have an inlet and outlet for an operating forced air HVAC system is considered a closet, and requires room venting as stated in the product literature. The room venting can be installed into the walls of the dryer enclosure, as well as the door, provided it will not be blocked after the dryer is installed. Refer to the product literature for minimum clearances between the product and the enclosure surfaces.

 

[High Desert]

They have louvered bi-fold doors opening into the rest of the house.

 

[mtlogcabin]

Check the net free area of the doors and may not be a problem then

 

[High Desert]

They oversized the openings so it should be okay. Thanks for your help.