Temp in electric room

I inspected a hotel today and they had an electrical room. When I opened the door, heat poured out and it was 110 degrees inside. The buyer asked what the temp in the room should be kept at for the electric to be safe and in good condition. I told him I would ask. Obviously the ac was not keeping the room cool enough.

Did the room have a return air duct, aside from the AC inlet?

Alot of hotels use PTAC for AC.

Did you get your answer, Mark?

I know it is in the open forum, but the Electrical section may get better results, if you still need them.

No answer yet, And I am in electrical?

Was there boiler equipment in the room? Do you have pics? Seems like temps in that range would not affect electrical service equipment. But could affect items such as wifi equipment and cable/satellite equipment. Was there central air or a PTAC unit(s) used to cool the area? Maintenance guys are notorious for stealing the PTAC from the electrical room (usually per their managers instructions) to keep an otherwise out of service guest room in service.


Yes, yes you are…:oops:

if i’m not mistaken
nec 310.16 wire baseline ambient starts at 30°C 86°F
temps above that derating has to be considered and calculated for
other components should also be considered and researched
imo…just add mech rm compliant a/c supply & return
better safe than sorry

thanks Barry!

Were there any large transformers in the room? If yes then they are creating the heat. Electric rooms with transformers are usually pretty warm.

One of the simplest solutions would be to have an exhaust fan vent the room to the exterior of the building.

I don’t think 110 degrees would be a big problem for the electrical equipment. Areas of the country that have high temps will experience this on a daily basis.

Who’s Barry? Just noticed your location and recalled recent weather there… doesn’t seem like an issue.

Isn’t that the Ambient Temperature there around now?

Tried to help.:neutral:

Barry had an answer posted, he must have deleted it. It was 90 in phoenix and 110 in the room.

Greetings Folks,

At this point you have to assume that the electrical contractor took into account the adjustments and corrections needed for the ambient temperature within the given room. While this is a BIG assumption, it is about all you can do at this point.

Since this is likely not a new installation you could look at the time of existence and determine the condition of the wire and cables as those are more than likely the weakest link in the evaluation chain.

Since chances are you would not be doing any detailed testing, such as ampacity readings and so on to determine otherwise, I would stick to the visual observation and use the language “equipment appears to be working properly at the time of the inspection”

Now, if you are getting into the weeds then clearly we can take some amp probe readings and correlate it to the amp draw and conductor sizes, number of conductors in the raceways and so on and see if any actual adjustments or corrections have been made but again probably a little beyond the scope of your inspection.

You could defer to the electronic components within such a room as I am sure their are XFMR’s in the room as well and suggest they consider reviewing the cooling aspect of the room for long term reliability but again that’s about all you can do without a detailed hands on evaluation. Other than that not enough details have been provided to assume anything other that what I have stated.

Good Luck.

Thank you Paul. Just thought that there was an ac goal temp for the room and that 110 was too warm…

Greetings Mark,

And their may be one but I guess that would be up to the facility and their staff since they are the ones who are gonna have to pay for it eventually. I have been in some toasty electrical equipment rooms in my day and when wiring within one we always had to take into account the ambient temperatures in our calculations.