Looking for fan cycle timer (switch)

[thoraxe]

My new building is going to have a powered fan and powered louver. I'd like to cycle the fan
15 minutes of the hour (to keep the air fresh and to vent stinky race car smells) and have an override.

I've found some in-wall switches that could drive the 1/4HP motor, but the timing selections all seem geared towards lighting (on from 5PM - 9PM!). There's a Leviton that has 50 programmable events:

https://www.leviton.com/en/products/vpt24-1pz

This might be the best bet, but it seems like overkill (I'd have to program basically every on and off).

I'd think something like a pool pump timer would partly be what I want, but my guess is that the pool timer doesn't have an "override".

What I really want is a simple cycling timer with an override that will let me run for N minutes and be off for X minutes.

Does anyone have suggestions? I searched for "fan timer" and didn't come up with much other than bathroom fan suggestions.

 

[lonestardiver]

The pool timer I have does have an override and you can set up several programs.

Aube by Honeywell TI040/U 7-Day Programmable Timer on EBay for about $82.

 

[TuxThePenguin]

That switch says it's rated for 1hp. It'll be fine. I don't know if it is the BEST switch of that type, but Leviton is a name brand and I'm sure it'll be good enough. Not some off-brand $2 imported garbage with ratings that are untrustworthy. If Leviton rates it 1hp, it should be a legitimate rating.

a 1hp motor is a 1hp motor, doesn't matter if it's a bathroom fan or a shop fan or what.

Programming every off and on is how every timer I hve used works, though maybe they sell "duty cycle timers" that would do what you want

Actually, Googling "duty cycle timer" does bring up results. Maybe look into that.

 

[vavet]

I use these at work sometimes, usually to control air valves, as long as they're spec'ed within the current range that you want, then it doesn't matter.

https://www.mcmaster.com/timer-relays/socket-mount-timer-relays-7/

You can set them on for 0.1 seconds all the way to to 1000+ hours...and then adjust the off time to match or be different from the on time.
They don't have an override per se, but you can always wire it in parallel with another switch.

I'm not sure how it should be wired/enclosed to make sure you're in compliance with good practice, NEC, IBC, etc. I use them low voltage DC, so it's not much of a concern.

 

[75gmck25]

If you use a water heater timer you would only get up to about six events each day, but its a rock-solid reliable timer that is available for 240 volts or 120 volts, and up to about 30 amps.

Bruce

 

[CoogarXR]

Get one of those heavy-duty mechanical timers that has the red and green tabs that you snap in for the on and off times. Have a friend with a 3D printer make you up a zillion of them and put them all around the dial, lol.

 

[cybrdyke]

Intermatic makes cycle timers. www.intermatic.com

https://www.intermatic.com/-/media/inriver/12683-8732.ashx/CT2000%20Instructions%20EN

CD

 

[Bert_]

Intermatic makes cycle timers. www.intermatic.com

https://www.intermatic.com/-/media/inriver/12683-8732.ashx/CT2000%20Instructions%20EN

CD

Glad somebody brought it up.

Cycle timer is the actual name of the product the op is looking for

 

[TuxThePenguin]

hey I just added one extra word when I replied

 

[nadogail]

A toothed wheel that turns at one Revolution Per Hour, operating a micro switch that controls a relay.

 

[CoogarXR]

A toothed wheel that turns at one Revolution Per Hour, operating a micro switch that controls a relay.

Or a fireplace bellows attached to the pendulum of a grandfather clock that inflates a balloon that takes exactly 900 pumps to fill. When fully inflated on the 900th pump, the balloon simultaneously presses an on/off switch and a mechanical air pressure release and the cycle starts over.

 

[nadogail]

Or a fireplace bellows attached to the pendulum of a grandfather clock that inflates a balloon that takes exactly 900 pumps to fill. When fully inflated on the 900th pump, the balloon simultaneously presses an on/off switch and a mechanical air pressure release and the cycle starts over.

Are you a student of Goldberg?

 

[Bert_]

A toothed wheel that turns at one Revolution Per Hour, operating a micro switch that controls a relay.

I realize you're probably joking but it's been done on a commercial level before.

I have a mid 70's radarange. For the defrost setting it uses a clock motor with an eccentric that pushes a micro switch that controls the main contactor with about a 50% duty cycle.

 

[nadogail]

I have a mid 70's radarange. For the defrost setting it uses a clock motor with an eccentric that pushes a micro switch that controls the main contactor with about a 50% duty cycle.

IMHO, Those old Amanas have yet to be equaled.

Like a Model A, they were built to "Work Fine and Last a Long Time "

 

[jlv03]

For the override, wire in a light switch or any other form of control device in parallel with the cycle timer control.