Trying to use motorized backdraft dampers - Growroom Designs & Equipment - International Cannagraphic Magazine Forums

packerfan79 · 09-24-2017, 08:38 PM

Ok so I want to use backdraft dampers to control my temps. All the dampers I can find are 24v. How do I connect it to my power that is 120v? I was planning on using these on my fan/ filter. One will open to the room, one will open to the exhaust. They will be opposite of each other. I think I need a transformer to drop the voltage, but how to accomplish this is a mystery to me.

moose eater · 09-24-2017, 10:14 PM

I believe you'd use a low-voltage relay, but why go motorized?

You are talking about your intake ventilation, right?

On my heat recovery ventilator, as well as my kitchen range hood, I've used light-weight-spring-loaded 'butterfly dampers'; they come with rubber gaskets surrounding the 'flaps' that form the damper halves, and fit neatly into what ever ducting you're using; preferably rigid ducting..

The negative pressure from your exhaust automatically pulls open the dampers if the pressure is sufficient.

The damper has a fairly thin pin that is typically placed in a vertical position, with a spring-tensioned half-circle damper to either side, that, when closed, with relatively neutral pressure, seats against the rubber gasket that surrounds the circumference of the damper.

It may well be that such a damper would work for you, and save you greater electricity use, as well as the headache of wiring, acquiring a relay, etc.

All of that depends in part on the air-tightness of your grow area, as to whether it can establish sufficient negative pressure when exhausting, to open the dampers.

Just a thought or three.

packerfan79 · 09-24-2017, 10:55 PM

No I need them for my exhaust, that way when it gets to cold I can,shut the exhaust to only recirculate and scrub the air. Other wise I would have to shut the filter/fan off, then smell will be a problem.

mushroombrew · 09-24-2017, 11:13 PM

Usually the damper piggy backs the fan circuit. The fan circuit is controlled by a thermostat.

If your damper motor is 24V then you need a low to high voltage relay.

The 24V transformer is always hot(live). When the fan circuit kicks on the relay flips and the 24V circuit closes so damper motor runs.

How to you intend to control the dampers? Thermostat?

packerfan79 · 09-24-2017, 11:41 PM

Quote:

Originally Posted by mushroombrew

Usually the damper piggy backs the fan circuit. The fan circuit is controlled by a thermostat.

If your damper motor is 24V then you need a low to high voltage relay.

The 24V transformer is always hot(live). When the fan circuit kicks on the relay flips and the 24V circuit closes so damper motor runs.

How to you intend to control the dampers? Thermostat?

I have a temp controller I was going to use if I could find a 120v motorized backdraft, but so far I can't find one. The controller has different adjustments for night and day temps.

I may just add another fan filter to scrub when the exhaust filter/fan is off. It gets pretty cold here last winter I ran the filter constantly and the night temps were pretty low like upper 40s. The cold stunted growth, what should have been a 10 week flower wound up being a 12 week flower. Quality was good but not on par with my normal runs.

Badfishy1 · 09-24-2017, 11:44 PM

Quote:

Originally Posted by packerfan79

I have a temp controller I was going to use if I could find a 120v motorized backdraft, but so far I can't find one. The controller has different adjustments for night and day temps.

I may just add another fan filter to scrub when the exhaust filter/fan is off. It gets pretty cold here last winter I ran the filter constantly and the night temps were pretty low like upper 40s. The cold stunted growth, what should have been a 10 week flower wound up being a 12 week flower. Quality was good but not on par with my normal runs.

You can find a low voltage relay with a 120 coil voltage. The 120v controls whether the contact is open or closed. But you will need to have a 120- 24v transformer to step down to feed the 24v damper. This 120v source will have to be separate from the 120 coil voltage

growingcrazy · 09-25-2017, 04:41 AM

https://www.ductanddampers.com/produc...s-SKU2446.html

Your looking at $125 for an 8" damper+... less parts with the 110v motor though.

Lazyman · 09-25-2017, 09:55 AM

24v DC is sprinkler valve voltage, any hardware store will sell you a sprinkler controller power supply for $20. 120vac in, 24v DC out.

AvidLerner · 09-25-2017, 12:29 PM

You need a 24v temp controller available on ebay for about $20

DocTim420 · 09-25-2017, 02:40 PM

Suncourt electric dampers come with a transformer, so you should not need to buy them separately. Keep your receipts, as they do come with a 3 year warranty and all the ones I used worked great....for about 2 years. The heavy duty transformer and the actuator are the two components that burned up constantly in my garden.

Like this one on Amazon...https://www.amazon.com/Suncourt-ZC10...lectric+damper

So, for damper placement--I would try to locate it so it won't be a PIA to replace it. And that transformer will get hot, too hot to touch, so find a good spot for it.

09-24-2017, 08:38 PM	#1
packerfan79 Senior Member Join Date: Jul 2012 Posts: 3,226	Trying to use motorized backdraft dampers Ok so I want to use backdraft dampers to control my temps. All the dampers I can find are 24v. How do I connect it to my power that is 120v? I was planning on using these on my fan/ filter. One will open to the room, one will open to the exhaust. They will be opposite of each other. I think I need a transformer to drop the voltage, but how to accomplish this is a mystery to me.
	Quote

09-24-2017, 10:55 PM	#3
packerfan79 Senior Member Join Date: Jul 2012 Posts: 3,226	No I need them for my exhaust, that way when it gets to cold I can,shut the exhaust to only recirculate and scrub the air. Other wise I would have to shut the filter/fan off, then smell will be a problem.
	Quote 1 members found this post helpful.

09-25-2017, 09:55 AM	#8
Lazyman Overkill is under-rated. Join Date: Jun 2009 Location: Norcal Posts: 5,186	24v DC is sprinkler valve voltage, any hardware store will sell you a sprinkler controller power supply for $20. 120vac in, 24v DC out. __________________ I'm fairly busy so please excuse my absence or slow responses to PM's! All about Growroom cooling:* Keepin' it cool man (my 1st published article) How to automate reservoir top offs or most anything water-related The only UV-B lighting thread worth a damn CO2 for dummies Big grow: The 36KW medical/perpetual basement
	Quote 2 members found this post helpful.

09-25-2017, 12:29 PM	#9
AvidLerner Member Join Date: Apr 2008 Location: Universe Posts: 447	You need a 24v temp controller available on ebay for about $20 __________________ I'm just a poor boy, I need no sympathy Because I'm easy come, easy go A little high, little low Anyway the wind blows, doesn't really matter to me, to me.
	Quote

09-24-2017, 10:14 PM	#2
moose eater Senior Member Join Date: Aug 2017 Location: Off a dead-end dirt road, near a river, out of town, in the hills and trees Posts: 1,178	I believe you'd use a low-voltage relay, but why go motorized? You are talking about your intake ventilation, right? On my heat recovery ventilator, as well as my kitchen range hood, I've used light-weight-spring-loaded 'butterfly dampers'; they come with rubber gaskets surrounding the 'flaps' that form the damper halves, and fit neatly into what ever ducting you're using; preferably rigid ducting.. The negative pressure from your exhaust automatically pulls open the dampers if the pressure is sufficient. The damper has a fairly thin pin that is typically placed in a vertical position, with a spring-tensioned half-circle damper to either side, that, when closed, with relatively neutral pressure, seats against the rubber gasket that surrounds the circumference of the damper. It may well be that such a damper would work for you, and save you greater electricity use, as well as the headache of wiring, acquiring a relay, etc. All of that depends in part on the air-tightness of your grow area, as to whether it can establish sufficient negative pressure when exhausting, to open the dampers. Just a thought or three.
	Quote

09-24-2017, 11:13 PM	#4
mushroombrew Senior Member Join Date: May 2009 Posts: 1,884	Usually the damper piggy backs the fan circuit. The fan circuit is controlled by a thermostat. If your damper motor is 24V then you need a low to high voltage relay. The 24V transformer is always hot(live). When the fan circuit kicks on the relay flips and the 24V circuit closes so damper motor runs. How to you intend to control the dampers? Thermostat?
	Quote

09-25-2017, 04:41 AM	#7
growingcrazy Member Join Date: May 2014 Location: Michigans sunset coast Posts: 771	https://www.ductanddampers.com/produc...s-SKU2446.html Your looking at $125 for an 8" damper+... less parts with the 110v motor though.
	Quote

09-25-2017, 02:40 PM	#10
DocTim420 The Doctor is OUT and has moved on... Join Date: Oct 2016 Posts: 1,192	Suncourt electric dampers come with a transformer, so you should not need to buy them separately. Keep your receipts, as they do come with a 3 year warranty and all the ones I used worked great....for about 2 years. The heavy duty transformer and the actuator are the two components that burned up constantly in my garden. Like this one on Amazon...https://www.amazon.com/Suncourt-ZC10...lectric+damper So, for damper placement--I would try to locate it so it won't be a PIA to replace it. And that transformer will get hot, too hot to touch, so find a good spot for it.
	Quote