elevator damper/fan wiring

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electricalperson

Senior Member
Location
massachusetts
here is what we are doing.

the HVAC contractor wants us to wire the damper at the top of the shaft and a fan inside the elevator room. there is a vent between the room and the shaft

the damper at the top is powered close and spring open. when it looses power it opens

the hvac guy gave us a UPS to install to power just the fan only. he DOES NOT (for reasons unknown) want the damper on the ups.

here is what he wants to do. when the fire alarm goes off he wants the damper at the top of the shaft to open (loose power) and the fan to kick on.

in normal operation a thermostat inside the elevator room will control the damper and the fan. if it gets too hot the damper opens and the fans kick on to remove the heat.

here is a diagram i drew up im not an artist so dont make fun of me. :grin: what does everyone think?
the thermostat in the drawing is in heat mode so therefor the damper is shut at the top and no fan is on. when it switches to cool it drops the power to the fan, turns on the relay for the fans thats fed off of the UPS circuit. hopefully this makes sense.

when i say street and street neutral i mean power thats not on the UPS circuit. the relays are shown in there non powered locations.
relay.jpg
 

cadpoint

Senior Member
Location
Durham, NC
I can't believe its the HVAC Guy thats having so much say about this elevator / application, and I can't believe there a air shaft between the elevator equipment room and the raceway.

I'm no wizard at elevator installs, but I do know they are highly regulated in my State, a lot of what the elevator man says go, cause we have to install to what the State Codes are for elevators and the HVAC Guy would be in line to answer to the elevator man because it will be for the total package of the elevator and the requirements that must be met, just like I had to, recently.:rolleyes:
 

electricalperson

Senior Member
Location
massachusetts
I can't believe its the HVAC Guy thats having so much say about this elevator / application, and I can't believe there a air shaft between the elevator equipment room and the raceway.

I'm no wizard at elevator installs, but I do know they are highly regulated in my State, a lot of what the elevator man says go, cause we have to install to what the State Codes are for elevators and the HVAC Guy would be in line to answer to the elevator man because it will be for the total package of the elevator and the requirements that must be met, just like I had to, recently.:rolleyes:

im just doing what the hvac guy says to do. im not sure if they spoke with otis or not but im sure they did. there is no smoke detector in the shaft or anything. they didnt tell us to install it. im doing exactly what the elevator company tells us to do. this is just a small elevator for the lobby and basement of the church. just 2 stops. the hvac guy is supplying the relays and everything i need to do the job i just make it work:grin:
 

Rewire

Senior Member
your diagram seems wrong.

The feed from the UPS should bypass the T-state and go directly to the fan

when the alarm trips the relay drops power to the motor so the vent opens now you need UPS to go directly to the fan

You need a relay that opens both hot and neutral of utility power while closing hot and neutral of UPS
 

electricalperson

Senior Member
Location
massachusetts
your diagram seems wrong.

The feed from the UPS should bypass the T-state and go directly to the fan

when the alarm trips the relay drops power to the motor so the vent opens now you need UPS to go directly to the fan

You need a relay that opens both hot and neutral of utility power while closing hot and neutral of UPS

the UPS relay has the feed from the FA relay on the normally closed terminal, the feed to the fan on the common terminal and constant power from the UPS

when the thermostat calls for cool it closes the coil of the relay and causes the contacts to move from NC to C. only time the NC contact will see power is when the FA relay switches from normally closed position to normally open transfering power from 1 of the C terminals to the NO terminal
 

electricalperson

Senior Member
Location
massachusetts
the FA relay coil will only be powered up during alarm condition with 24v from the FACP. when that relay is powered up it cuts power to the damper and sends power directly to the fan. the way its wired that fan will get turned on during a fire no matter what. if that thermostat wants the fan on the fan will turn on. if theres a fire alarm when that fan is already on, when the thermostat is satisfied that fan will still remain on because the FA relay will be switched from normally closed to normally open cutting power to the damper and sending power to the normally closed terminal of the other relay turning that fan on
 
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Davis9

Senior Member
Location
MA,NH
This should all be on the stamped prints. If it isn't then the FA designer doesn't know about it.

Tom:confused:
 

electricalperson

Senior Member
Location
massachusetts
This should all be on the stamped prints. If it isn't then the FA designer doesn't know about it.

Tom:confused:

the company i worked for designed the FA system. its not very complex. the city approved of it.

nobody told us how to do this system until today. the building has been planned for months and months and the elevator guys didnt tell us anything about codes or other requirements. the elevator installers are the guys who told us this stuff a few days ago
 

electricalperson

Senior Member
Location
massachusetts
the HVAC contractor is responsible for the elevator shaft venting. they came up with the bright idea and im the guy wiring it for them. whatever they said to the elevator company is unknown to me. they had to install a 2 hour fire rated vent and had a 2 hour fire rated shaft built around the duct going to the roof
 

Davis9

Senior Member
Location
MA,NH
the HVAC contractor is responsible for the elevator shaft venting. they came up with the bright idea and im the guy wiring it for them. whatever they said to the elevator company is unknown to me. they had to install a 2 hour fire rated vent and had a 2 hour fire rated shaft built around the duct going to the roof

You may want to check with the FD and Elevator guys, how will the FD shut off the fan? Will they always want it on?

Tom

Won't the UPS be in Parallel through the 2 normal controls(FA and T-stat) that way it works normally unless there is a power failure.
 

electricalperson

Senior Member
Location
massachusetts
You may want to check with the FD and Elevator guys, how will the FD shut off the fan? Will they always want it on?

Tom

Won't the UPS be in Parallel through the 2 normal controls(FA and T-stat) that way it works normally unless there is a power failure.

they can unplug the UPS. its a 250 dollar cheap unit.
 

electricalperson

Senior Member
Location
massachusetts
I doubt the FD will want to run around unplugging stuff, it should have a key switch/similar with/near the FA panel. This needs to be discussed with them(FD) Just my HO though.

Tom:smile:

we can probably program a button on the FACP located near the front door to disable the fan by pulling in that relay to remove power to the fan

they will probably want something more fail safe than that i bet. we will find out i suppose :smile: im just the guy doing the work the boss wants me to do
 
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electricalperson

Senior Member
Location
massachusetts
I hear you, I bet you'll be the guy at the inspection too. I hate surprises at inspection time.

Tom;)

i wont be too surprised. i dont care if we have to change it. its not my fault and i never done any elevators before. its a good experience at least.

do you think there is anything wrong with my diagram at least?
 

R Bob

Senior Member
Location
Chantilly, VA
here is what we are doing.

when the fire alarm goes off he wants the damper at the top of the shaft to open (loose power) and the fan to kick on.

in normal operation a thermostat inside the elevator room will control the damper and the fan.
relay.jpg

your diagram seems wrong.

The feed from the UPS should bypass the T-state and go directly to the fan

when the alarm trips the relay drops power to the motor so the vent opens now you need UPS to go directly to the fan

You need a relay that opens both hot and neutral of utility power while closing hot and neutral of UPS

As it stands now the T-stat will control the fan no matter what the power source is.
 

R Bob

Senior Member
Location
Chantilly, VA
This should all be on the stamped prints. If it isn't then the FA designer doesn't know about it.

Tom:confused:

I tend to agree with this logic.

There are several critical issues that need to be coordinated:
1. Elevator
2. Ventilation of the Elevator Mech. room and hoistway.
3. Fire Alarm system.
4. Occupancy=church=Place of Assembly.

There needs to be an engineered sequence of operation with specifications and drawings.

This is not an appropriate situation for a "practical man's engineering".
 
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