heat piping over a disconnect

[Charlie H]

hi all im just asking about this and just trying to see what the code is .

im piping out some big pumps and they have a disconnect and a VFD mounted on a stand next to the pumps .this room is small and i dont have a lot of room to run my pipes around it so can i go over them . i know i cant run them over a panel or transformer .

i dont know if the electrician pulling a trick on me
i have ran pipes over them in the past and the inspector never said it was wrong

i looked through this forum before i posted and did not see what i am looking for

so thanks if you help clear this up for me

 

[Dennis Alwon]

im piping out some big pumps and they have a disconnect and a VFD mounted on a stand next to the pumps .this room is small and i dont have a lot of room to run my pipes around it so can i go over them . i know i cant run them over a panel or transformer .

I will preface this by saying I ain't no expert but as I read art. 110.26(F) I would say it is not a problem as long as there is no motor control centers in this space. If we are talking just disconnect I think you are okay.

Hopefully others will chime in and correct me if I am wrong.

 

[bobgorno]

Personal opinion. Disconnect is probably OK with pipes run above. VFD might be subject to interpretation and conditions. Large medium voltage VFD might be an issue. A pump VFD.....really, who cares, maybe not a big deal. Make sure there are no fittings in the pipes above the equipment. Make sure your pipe is not for a heat transfer fluid that is a potential flammable source if operated above its flashpoint......such as Syltherm or other hot oil types.

 

[ironman3452]

what does your jha say, that way you are cleared of any trouble that may come your way, by the way get it in writing as to what the jha says, remember cya.

 

[ohm]

Personal opinion. Disconnect is probably OK with pipes run above. VFD might be subject to interpretation and conditions. Large medium voltage VFD might be an issue. A pump VFD.....really, who cares, maybe not a big deal. Make sure there are no fittings in the pipes above the equipment. Make sure your pipe is not for a heat transfer fluid that is a potential flammable source if operated above its flashpoint......such as Syltherm or other hot oil types.

Good call. I once heard of a computer room in a huge company getting flooded when a coil in steam room heater ruptured. The heater was on saturated steam which permeated the room with hot water and shut dowm their main computers for days (& millions). The steam heater was a total loss after the IT department head kicked it around the room for ten minutes.

 

[Charlie H]

thanks for the help
the electrician called the inspector and he said it is not a problem but the electrician did not tell me he said some thing to the duct guys and did not want to tell me because i would have said i told you so :grin:

we did this many times and never had to change it

when i run pipes over pumps ,switches and other things like this i never put fittings over them

thanks again for your help and i hope i will be able to help some one out here some day :smile:

 

[Charlie H]

i asked the electrician how many times did he see a pipe that springs a leak go down verses out to the side when the pipe has pressure in it

some of the water goes down but a good amount sprays up or out to the side so it can still hit a panel or transformer
so you never know what could happen

 

[weressl]

hi all im just asking about this and just trying to see what the code is .

im piping out some big pumps and they have a disconnect and a VFD mounted on a stand next to the pumps .this room is small and i dont have a lot of room to run my pipes around it so can i go over them . i know i cant run them over a panel or transformer .

i dont know if the electrician pulling a trick on me
i have ran pipes over them in the past and the inspector never said it was wrong

i looked through this forum before i posted and did not see what i am looking for

so thanks if you help clear this up for me

I think that 110.26(F) is applicable in this case.

No piping of any kind SHOULD be run over electrical equipment. This SHOULD be in the NEC, but it isn't. So any engineering firm or any large company with an engineering staff worth their salt would write into their specifications. Some goes so far the say that parallel runs of pipes are not permitted over electrical conduit banks or trays.

 

[ce2two]

ce2two sparky

ce2two sparky

back in 1986 at general dynamics ,pomona ca, worked in waste water treatment area ,worked down in a basement filled with nothing but motor contol centers ,relay panels,stop start stations etc ,conduit running all over the place chemicals dripping down on to the M.C.C. and the fireworks came with the dripping chemicals .....poorly designed/layed out...........yikes it was not fun???????????????

 

[ohm]

I think that 110.26(F) is applicable in this case.

No piping of any kind SHOULD be run over electrical equipment. This SHOULD be in the NEC, but it isn't. So any engineering firm or any large company with an engineering staff worth their salt would write into their specifications. Some goes so far the say that parallel runs of pipes are not permitted over electrical conduit banks or trays.

Weressel, 110.26 talks of working space for personnel safety and dedicated space for switchboard, panelboard, distribution board and motor control center protection protection.

Dedicated space extends to 6 ft. above the equipment (above) but as exhibit 110.19 (2005 ed.) clearly shows even sprinkler heads are allowed just 7 ft. in front of the equipment.

I agree this is not a good situation but my company has to tolerate million GPM deluge systems being installed all around our MEMA 3R & 4X disconnects for fire protection. Further, 110.26 (F) has an exception which specifically allows control equipment to be located outside of dedicated space to be within sight of operating machinery etc.

As you stated good design must prevail.

 

[petersonra]

sometimes it is a matter of what is practical too. these days to save money, everyone wants to jam 10 pounds of youknowwhat in a 5 pound bag.

i have had to design stuff lately that i would never have done in the past just so it fits in the space available. sometimes clever design makes it tolerable, but sometimes i have been forced by reality to make it very hard to work on stuff, short of disassembling it.

 

[ron]

weressl,
Are you sure 110.26(F) says "should"?
I only have a 2002 nearby, but mine says "shall".
I understand "shall" to mean that you have to.

 

[weressl]

weressl,
Are you sure 110.26(F) says "should"?
I only have a 2002 nearby, but mine says "shall".
I understand "shall" to mean that you have to.

(a)​

​

Dedicated Electrical Space. The space equal to the
width and depth of the equipment and extending from the
floor to a height of 1.8 m (6 ft) above the equipment or to
the structural ceiling, whichever is lower, shall be dedicated
to the electrical installation. No piping, ducts, leak protection
apparatus, or other equipment foreign to the electrical​

installation shall be located in this zone.


Duh.......:roll:

 

[ohm]

(a)​

​

Dedicated Electrical Space. The space equal to the
width and depth of the equipment and extending from the
floor to a height of 1.8 m (6 ft) above the equipment or to
the structural ceiling, whichever is lower, shall be dedicated
to the electrical installation. No piping, ducts, leak protection
apparatus, or other equipment foreign to the electrical​

installation shall be located in this zone.


Duh.......:roll:

It's funny that water, steam, chemical piping etc. can't be located closer than 6 ft above control centes etc. (i.e. the dedicated zone but the piping IS allowed 7 ft above above it, which is out of the dedicated space.

Did the NEC also repeal the Law of Gravity? Other than the force that the contents of this piping might impact the equipment, if a leak occurs, what's the difference?

Good design above the dedicated space should prevail, but doesn't have to prevail.:-?