Evaporative cooler Tstat - automating it possible?

[alia176]

Hey guys,

Those of you with Evaporative (swamp) coolers may know that there is not a huge selection of control Tstats for these things. Other than the usual 2/4/8 hour time delay, I haven't been able to find a controller that can be programmed like a normal furnace/A/C Programmable Tstat.

I do happen to have a Honeywell heat/A/C programmable Tstat on another wall to control our baseboard heater. So I was thinking of using a 24vac relay with two poles to turn the power on/off on my swamp cooler Tstat. Running the wire is going to be a huge challenge.

The swamp cooler controller is a low voltage Tstat - meaning that the control power is located inside the cooler, housed inside a NEMA 4 enclosure. 24vac (two wires wires) comes out of this box and goes to the controller inside the house. Two more wires come out of the remote mounted Tstat to control the two speed fan and the water pump (pad wetting).

What say you?

 

[splitshot]

We just use the std Mastercool unit, works great for us (most of the time).

Wife and kids think the dial needs to go all the way to the right or the left. I'm sure we'd have the same problem with a programmable unit.

 

[alia176]

Wife and kids think the dial needs to go all the way to the right or the left. I'm sure we'd have the same problem with a programmable unit.

LOL! That's funny.

 

[porten1134]

well its a little vague for troubleshooting purposes,but given the info provided it sounds like you have two options.....on or off.now there may be some kinda fancy signaling going on but for the most part if there is only two low voltage type wires coming out of the control box its a single pole relay. most swampys have 5 wires ran to them. one is the grounded wire( nuetral...hopefully its white), one for the pump, one for low speed, one for high speed, and if your really lucky a bare copper grounding wire. the little rotary switch thingy will energize one or two at a time depending on the setting( low cool will energize the pump and the low speed, high cool the pump and high speed....etc.)

you'd have to see how the wiring for all this would land in the relay that the low voltage controls. as a general rule of thumb the relay may have the option to switch many wires at once. but if your only looking at two wires coming out of it, more than likely the relay only has two positions; on and off. it sounds like you might have to pick one setting(high cool, low cool..etc) and suffer through switching it on or off with the t-stat.

good luck

 

[alia176]

well its a little vague for troubleshooting purposes,but given the info provided it sounds like you have two options.....on or off.now there may be some kinda fancy signaling going on but for the most part if there is only two low voltage type wires coming out of the control box its a single pole relay. most swampys have 5 wires ran to them. one is the grounded wire( nuetral...hopefully its white), one for the pump, one for low speed, one for high speed, and if your really lucky a bare copper grounding wire. the little rotary switch thingy will energize one or two at a time depending on the setting( low cool will energize the pump and the low speed, high cool the pump and high speed....etc.)

you'd have to see how the wiring for all this would land in the relay that the low voltage controls. as a general rule of thumb the relay may have the option to switch many wires at once. but if your only looking at two wires coming out of it, more than likely the relay only has two positions; on and off. it sounds like you might have to pick one setting(high cool, low cool..etc) and suffer through switching it on or off with the t-stat.

good luck

Yup, most Tstat controllers accept 120/240vac directly into them and send out wires to control the pump and fan. In this case, all high voltage is located at the control box located inside the swamp cooler and only 24vac is sent out to the Tstat inside the dwelling for control purposes.

With the relay my plan is to simply turn power on/off to this swampy controller. Once the power is on, the swamp cooler will simply run until the power is shut off. I'm thinking that by going this route, the swampy Tstat will do the usual pad wetting cycle and then turn on the blower motor.

My Honeywell programmable controller can do a better job of controlling the temp than the swampy POS. Additionally, it can run 24/7 w/o manual intervention, especially during the night while we're asleep. At least that's my theory anyway!

Thanks.