Exhaust fan both timer and speed control and GFCI protection

[brother]

Does anyone know of a single gang /yoke switch that has both timer and speed control for an exhaust fan ? Not sure of a building code but others claim air balancing is needed and speed control is how they do it even though the ductwork for this exhaust fan is completely independent of the main ductwork.

Also does the nec require gfci protection for the switch in commercial, it's for a 0.05 hp exhaust fan for a dog washer area. I have searched but did not find a requirement that someone else claimed it was? It's not installed in the wet area its outside it next to regular light switches.

 

[ptonsparky]

I would not bother with a speed control for a .05 hp fan. Totally waste of time and money.

GFCI protection would depend on local rules but I would doubt it.

 

[kwired]

By air balancing if you mean adjusting balance of air pressure because of the negative pressure the exhaust fan will create, speed change only lessens the negative pressure . To get total balancing you need make up air for what you are removing. You don't really get much effectiveness from "exhausting" if you don't have make up air either, this has only gotten worse as time has gone on and we were constructing building with better air tightness, long time ago there was make up air leaking around doors, windows, penetrations through walls, like plumbing, electric, etc . that were not sealed as well as they usually are nowadays.

GFCI protection isn't required for switches. General GFCI protection rules require it for receptacle outlets in locations mentioned in 210.8 (A) and (B) or for specific "outlets" mentioned in other portions of 210.8 or in other code sections for specific equipment. Though many those specific equipment items more recently got moved to 210.8

 

[brother]

I would not bother with a speed control for a .05 hp fan. Totally waste of time and money.

The issue here is that they claim its 'required' to pass mechanical inspection to balance the air. So the present way they do that is by controlling the speed of the fan which will limit the exhaust pressure (negative), But like you said, usually they will need to have some degree of 'supply air coming in to help balance if that is really an issue. I question if it is really necessary to do that because they installed the exhaust fan on its own system and I am not sure if they even have a 'supply' air even being pushed into this room/area. Also, the horse power on that exhaust fan, 0.05. but it is 210 cfm. So it does move some air if necessary. Its only for a little bit of moisture from the wash station for pets.

My question about the single/gang switch that can be a timer and speed control would be an easier less time consuming install. So is there a switch made this way?

 

[bgard]

The issue here is that they claim its 'required' to pass mechanical inspection to balance the air. So the present way they do that is by controlling the speed of the fan which will limit the exhaust pressure (negative), But like you said, usually they will need to have some degree of 'supply air coming in to help balance if that is really an issue. I question if it is really necessary to do that because they installed the exhaust fan on its own system and I am not sure if they even have a 'supply' air even being pushed into this room/area. Also, the horse power on that exhaust fan, 0.05. but it is 210 cfm. So it does move some air if necessary. Its only for a little bit of moisture from the wash station for pets.

My question about the single/gang switch that can be a timer and speed control would be an easier less time consuming install. So is there a switch made this way?

Grainger / Dayton, 35YV94

 

[LarryFine]

Grainger / Dayton, 35YV94

It may not be a universal device. See the bottom link.

https://www.grainger.com/product/DAYTON-Speed-Control-Touch-Button-35YV94?searchQuery=35YV94&searchBar=true&tier=Not+Applicable

Dayton Speed Control, Touch, 115/230V, 0.5/0.25A 35YV94 | Zoro

Order Dayton Speed Control, Touch, 115/230V, 0.5/0.25A, 35YV94 at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.

www.zoro.com

Item Details: 35YV94 | Products | SFA

Dayton®, Venco® HVAC - Your Ventilation Information Resource - Exclusively from Grainger

www.solutionsforair.com

When used with a Dayton EC motor can maximize the efficiency of the ventilation system. Controls can be used in manual or automated operation to control the demand of the ventilation system. Recommended for use in commercial buildings and restaurants. These controls allow the user to manually adjust a fan's speed from a remote location and mounts to a wall using a 2x4 junction box.

• Includes a 24 volt transformer to power the remote and motor controls
• Transformer supplies low voltage to the speed control accepting dual voltage (115/208-240V)

https://www.grainger.com/ec/pdf/Dayton-Speed-Control-Kit-Operating-Instructions.pdf

 

[kwired]

The issue here is that they claim its 'required' to pass mechanical inspection to balance the air. So the present way they do that is by controlling the speed of the fan which will limit the exhaust pressure (negative), But like you said, usually they will need to have some degree of 'supply air coming in to help balance if that is really an issue. I question if it is really necessary to do that because they installed the exhaust fan on its own system and I am not sure if they even have a 'supply' air even being pushed into this room/area. Also, the horse power on that exhaust fan, 0.05. but it is 210 cfm. So it does move some air if necessary. Its only for a little bit of moisture from the wash station for pets.

My question about the single/gang switch that can be a timer and speed control would be an easier less time consuming install. So is there a switch made this way?

210 cfm would be at 0 static pressure. The CFM changes as static pressure changes. Any ducting involved can also change pressure across the fan itself.

 

[brother]

It may not be a universal device. See the bottom link.

https://www.grainger.com/product/DAYTON-Speed-Control-Touch-Button-35YV94?searchQuery=35YV94&searchBar=true&tier=Not+Applicable

Dayton Speed Control, Touch, 115/230V, 0.5/0.25A 35YV94 | Zoro

Order Dayton Speed Control, Touch, 115/230V, 0.5/0.25A, 35YV94 at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.

www.zoro.com

Item Details: 35YV94 | Products | SFA

Dayton®, Venco® HVAC - Your Ventilation Information Resource - Exclusively from Grainger

www.solutionsforair.com

When used with a Dayton EC motor can maximize the efficiency of the ventilation system. Controls can be used in manual or automated operation to control the demand of the ventilation system. Recommended for use in commercial buildings and restaurants. These controls allow the user to manually adjust a fan's speed from a remote location and mounts to a wall using a 2x4 junction box.

• Includes a 24 volt transformer to power the remote and motor controls
• Transformer supplies low voltage to the speed control accepting dual voltage (115/208-240V)

https://www.grainger.com/ec/pdf/Dayton-Speed-Control-Kit-Operating-Instructions.pdf

View attachment 2571919

Thanks for the info
I am looking for something more basic, where it just use the existing 120v wiring at the switch box without having to run the 24volt low voltage

I have seen the basic vari speed 120 v switches and basic spring loaded timer switch, but I would like to find a device that has both without having to run extra wire. Assuming if they even make them.

 

[LarryFine]

You're welcome. It's expensive, too! It would cost less to change to a 2g box.