Link to dingbo
(Mechanical)
(OP)
11 Sep 15 20:23Hello everyone,
I was looking for requirements on ventilating a generator room. Does it have to only be naturally ventilated?
I've looked at NFPA 110 () but it seems ambiguous.
Replies continue below
(Mechanical)
14 Sep 15 00:31Do an engine search. By just typing "indoor generator fresh air requirements" I got multiple hits.
(Mechanical)
14 Sep 15 13:02You will need both combustion and cooling air which will be cataloged by generator manufacturers.
(Mechanical)
(OP)
14 Sep 15 19:42Well, for the cooling air, can it be coming from a cooling coil?
Because one of the concerns is that if we're using a cooling coil and if it failed at the same time that the generator was required, then you'd end up with inadequate cooling and so we're trying to see if there is any code requirement mandating only the use of OA dampers to condition the generator room.
(Mechanical)
15 Sep 15 14:21When you say cooling coil, are you referring to a radiator being part of the generator? As stated above, manufacturers' catalog will provide you all the info.
(Mechanical)
(OP)
15 Sep 15 19:36No, the radiator itself is mounted on the roof. But we'd still need to handle the heat load from the generator. I'll look up the manufacturer's specs and see what they have to say.
Thanks chicopee and willard3 for your advice.
(Mechanical)
16 Sep 15 19:43NFPA 110 () consistently uses the word "ventilation" when discussing cooling of the generator room.
The definitions section of NFPA 110 says for words that aren't specifically defined in the standard use the common dictionary definition.
The common dictionary definition for "ventilation" is "provide fresh air from outside".
So, yes it has to be only natural ventilation.
(Mechanical)
(OP)
18 Sep 15 21:52I was thinking on the same lines. Thanks MintJulep!
(Mechanical)
29 Sep 15 11:14I am from marine sector and always use ISO
(Mechanical)
12 Oct 15 14:48No - wrong interpretation of the word Ventilation.
ventilation does not mean natural ventilation in our trade, you should not go by what the dictionary says, but by how your industry defines the word ventilation, i.e. as defined by IMC, not by the webster.
IMC defines Ventilation as follows:
Ventilation is defined as the Natural or Mechanical process of supplying air.
Ventilation Air is defined as the portion of any supply air that comes from outside plus any recirculated air.
Use exhaust fan with Outdoor intake with filters, dampers, thermostat, the classic ventilation, account for combustion air. That's it.
(Mechanical)
12 Oct 15 15:01Quote (NFPA 110 ())
Where terms are not defined in this chapter or within another chapter they shall be defined using their ordinarily accepted meanings within the context in which they are used. Merriam-Webster's Collegiate Dictionary, 11th edition shall be the source for the ordinarily accepted meaning.
Sorry cry22, but you're not right.NFPA 110 explicitly tells you to look it up in the dictionary.
(Mechanical)
12 Oct 15 15:17Mint,
Nope, allow me to disagree.
NFPA 110 is not one of the referenced standards in IMC. We design per code. The code is IMC, not NFPA 110.
NFPA is a guideline unless referenced by IMC.
and I agree with IMC for the Ventilation definition, not with NFPA 110.
AND, if you read your quoted text correctly, it says "ordinarily accepted meanings within the context they are used" - What NFPA is saying in the quoted text is that when NO specific definition is known, then you rely on the dictionary. But there is a Known definition as defined in IMC.
I love it, we talk like lawyers.
(Mechanical)
12 Oct 15 20:06Look at the generator manufacturer literature, they should refer to the installation requirement.
(Mechanical)
13 Oct 15 01:20Here is a source for details and schedules for most of young engineers that I am sure will find helpfulcheck the emergency gen set detail from the same site below, this one has a radiator indoor, just edit to suit the remote radiator application. The remote radiator application is actually much simpler.: gen set manufacturers do not issue installation details, they just issue air flow requirements.
(Mechanical)
13 Oct 15 03:05Cry 22
air flow of what?
(Mechanical)
13 Oct 15 13:05317
air flow for radiator (when radiator part of gen set), combustion air flow, alternator cooling air flow.
(Mechanical)
13 Oct 15 18:48cr.
Young engineers are happy with grandpa gift.
also, didn't Caterpillar give you installation details such as clearances around generator, ambient temperature, room temperature and condition if it was for indoor application.
(Mechanical)
14 Oct 15 21:24my answer would be no, it does not have to be only naturally ventilated.Quote (sidd20)
Does it have to only be naturally ventilated?
Have to agree with Cry22 regarding the definitions and that IMC is the governing code.IMC defines "" as "And "" as "Furthermore, IMC does not specifically defineventilation, but does define "" as "Ifis ventilation using nonpowered means, thenwould be the use of fans to force the ventilation air through the designated space.Doing a word search through NFPA 110, I do not see anywhere specifying that the ventilation air to be either natural or mechanical. Thus I would interpret NFPA 110 to mean that the ventilation air can be either natural or mechanical in nature.Going back to Sidd20's OP and his questionmy answer would be no, it does not have to beventilated.
(Mechanical)
15 Oct 15 04:06Why IMC is governing code?
(Mechanical)
19 Oct 15 13:53In the US, at least, each state determines a code to which they want buildings constructed to. For most states this is ICC's building codes including IMC. Select states such as Florida and New York have their own building code which are based on IMC. DOD and other US governmental agencies use IMC with select changes. I have yet to see any of these modified versions of IMC change definitions.
(Mechanical)
19 Oct 15 20:11cry22 and dbill74 are on the right track with this. Where there are defined terms in an applicable code, use the code definition.
IMC may very well govern, check with your local authority having jurisdiction.
(Mechanical)
For more genset roominformation, please contact us. We will provide professional answers.
19 Oct 15 20:17If you have a genset with a remote radiator you will still need an enormous amount of ventilation air to cool the generator room. I recently did a generator room with two kVa water cooled generators and required 25,000L/s ventilation to maintain a 18 degree temperature rise in the room over ambient temperature.
You need to talk to your generator supplier to confirm the heat that the generator radiates into the room, determine the maximum temperature you can allow in the room, your design ambient temperature and then calculate the air flow. Plus you need to make allowance for combustion air which won't be as large, but is not insignificant either.
The next issue will be acoustics and large airflows need large attenuators!
(Mining)
20 Oct 15 00:35wish I'd had this problem when running two kW gennies in the high arctic when April was still minus 40
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Enclosures are growing in importance for generator use, especially in industrial applications. Increasingly, building designers are looking for ways to get the most out of every space they have within a building, moving the generator set outdoors. In large-scale renovations, upgrading an area of a building to meet the power demands and larger generators requires a significant amount of investment and retrofitting. It&#;s often easier and more efficient to place the generator outdoors. The right housing allows this to happen.
A well-built and suitable enclosure offers a number of advantages. When an industrial generator is outdoors, it is more likely to receive the thorough and frequent maintenance it needs to maintain its long life. The overall procedures are less likely to require complex processes such as removing the engine. The filter life tends to be longer as well.
Generator enclosures can be grouped into three types, often categorized by their primary function:
Weather-protective enclosures &#; enclosures can be designed to be completely waterproof.
Sound-attenuating enclosures &#; specifically designed to keep areas quiet.
Walk-in enclosures &#; allow for more room and space to manage and maintain the system than may be possible indoors.
Weather-Protective Enclosures
Numerous options exist for generator enclosures. Metal enclosures are a common option, but they often lack a few key benefits of weather-protective enclosures. For example, while a traditional metal enclosure can offer protection from the rain and wind, it doesn&#;t offer any protection from changing temperatures. They offer some airflow and ventilation, but not enough to offer extensive protection for some diesel generators. Weather-protective enclosures can offer this, due to their tight design.
While steel or aluminum can work in some situations, they should always be weatherproof in their design to ensure complete protection of the generator. A comprehensive design should minimize all risks to the generator set.
Sound-Attenuating Enclosures
Soundproofing enclosures is nearly always necessary. Sound-attenuating enclosures are required in areas where outdoor generator use is limited unless noise reduction is built into the enclosure. These enclosures are a bit larger and can cost a bit more than a basic weatherproofed system, but they allow for reduced acoustics overall.
This type of housing works to reduce the noise significantly, though not all will reduce the sound completely. To accomplish this, the enclosure tends to be taller and longer in overall size to allow for added insulation within the walls of the housing. They often feature a muffler on the inside of the enclosure. Many designs also extend beyond the radiator and feature baffles that help to further reduce the noise production of the system.
Walk-In Enclosures
Best practice for any generator set is to follow the manufacturer recommendations. Having an enclosure that provides complete protection for the generator set, including noise and weather protection, along with being fireproof, takes creating a customized option. Walk-in enclosures can be the best fit in these applications.
Walk-in enclosures are often designed to provide for all of these benefits &#; they are weatherproof, soundproof, fireproof, and fully insulated to be quiet. Because they are custom built, they can be designed to fit the specifications of any make and model of generator, including all backup generator models and routinely used systems. At the very least, the generator set enclosure should be designed for the specific class and type of system.
Other Enclosure Design Considerations
When planning for an enclosure, there are other key aspects of the design to take into consideration. The housing selected should provide the highest level of protection possible, but it also has to meet with all manufacturer requirements along with any federal, state, or local regulations. Consider the following aspects of enclosure design.
Ventilation & Temperature
All generators require good ventilation and temperature control. Without this, the generator could create a health hazard. Temperature is also important. Generators can only maintain the power output they are rated for if the temperature flowing through the enclosure is maintained and never exceeds the cooling system ambient temp rating. Proper flow-through ventilation allows the generator set to maintain the optimum operating temperature range.
In most situations the housing should include an advanced radiator along with fans to control the engine and generator operating temps even when the outdoor environment is less than ideal. It&#;s important to ensure intake and outflow of air is never obstructed.
Space
When planning for the housing unit, it&#;s essential to consider the entire system and how it will be used. This should include for service and maintenance needs based on the manufacturer&#;s requirements. The enclosure should also be expandable. Over time, the location&#;s power needs may change, requiring the use of a new generator. In other cases, a standby generator may be added at a later date. When configuring the enclosure, ensure all of these needs can be met.
Security
It&#;s not uncommon for generators to be accessed by third parties and even vandalized. At Worldwide Power Products we rent out a lot of generators and security is sometimes overlooked due to them being a temporary feature on-site or in the field. Also susceptible are industrial generators located in more remote areas. This vulnerability can compromise the generator. For this reason, design the enclosure to provide the highest level of security possible. This should include methods to lock all access points including all access to connections, valves, and switches. The fuel tank and system controls should always be secured. There are several other security steps you can take &#; ranging from rudimentary and inexpensive to comprehensive and expensive &#; to ensure the safety of your generator.
Fuel
In some cases, it is beneficial to choose an enclosure with an integrated high-capacity fuel tank. This allows for better protection of the fuel lines and the connections for them, enhancing security and overall function. If this is the route decided, be sure to choose those that offer dual-wall construction. Solutions should be put in place to handle accidents including fuel leaks and overflows.
Appearance
Though appearance may not seem like an important component, they are visible to the public. As such, they should be attractive enough to not take away from the plant itself. Choose materials, colors, and design features that allow the enclosure to blend in well with the surrounding area. It should always look clean and well-cared for to reflect positively on the business itself. Some designs are meant to look good, but they can also be built to be more durable. With a higher quality of durable exterior paint and 12-gauge, coated-steel, they maintain a professional look long-term. This should last for years, be easy to maintain, and should remain corrosion-free.
Construction Materials
Enclosure materials are just as important. Sheet metal is a common option because it can be beneficial to weather and soundproofing, if the metal itself is the right thickness. Many times, powder coating the metal enclosure is ideal as it can help to minimize corrosion risks, fading of paint, and any damage to the metal itself. A secondary option is aluminum. This is best in areas where humidity or high saline ambient air is common. Aluminum enclosures are beneficial in coastal areas, for example.
A well-designed enclosure should account for the location it is being placed in along with the type and specifications of the generator, and the way it will be used.
Are you interested in learning more about open type generator set? Contact us today to secure an expert consultation!