HVAC question

[supermanotorious]

I just built a misting system for my a/c unit, it's a Goodman packaged model. I control the water flow through a sprinkler solenoid but the problem is I'm not getting 24V from the contactor's coil on the a/c unit. The a/c unit is running and running well. Why am I not seeing 24V across this coil?!

I didn't think the unit would operate unless 24V was across the coil

 

[Goat]

Use a volt ohm meter and check voltage at all connections.. And make sure you wear rubber gloves.

 

[supermanotorious]

see how I am testing the coil? I did test the 240v terminals and there is power on both sides, the unit does not run nonstop as if the shunt welded itself to the input and output, I'm baffled why no 24v across the coil

---------- Post added at 03:57 PM ---------- Previous post was at 03:32 PM ----------

My compressor works just fine, how is it doing that with no 24V?!

https://www.youtube.com/watch?v=IALLkqXygsU

---------- Post added at 04:31 PM ---------- Previous post was at 03:57 PM ----------

wait, can the a/c be on and cooling without the compressor running???? maybe the compressor didnt need to kick on

 

[itsid]

two questions, just to rule that out basically..
1) you sure you measured 24V AC
(not 24V DC by accident, the 60Hz signal may corrupt the reading in DC mode)
and
2) in case you use a digital voltmeter as in the yt vid, make sure it's working when set to the voltage range in question.
most ac readers will happily accept a DC source (with just telling you it's been dc not ac)
some however don't.
check it's working and not just a corroded or worn out contact on the selector.
(happened to me no diode test no more )


Also check the test leads are connected properly
(sometimes you need to use another set of sockets for certain ranges)
sometimes a lead is just broken (with high voltages leaking through and thus can still be read, lower not)
And sometimes the contact you're probing is just corroded (doesn't look like in your pics tbh.. but still worth to take a closer look)

'sid

Since I don't know the device you're testing I cannot be of valuable help I'm afraid..
would need the wiring diagram to answer the last question really

 

[anickode]

Are you sure you're on the right wires?

Try the two yellows. Different brands of coil will likely be configured differently.

 

[supermanotorious]

OMG, itsid to the rescue, this is the second or third time of my entire life I tried to measure AC with a DC meter, honestly though when I hear of low voltage I automatically think of DC

the system is now wired up and doing what it should, video coming...

https://www.youtube.com/watch?v=Z3jTIXHHbS4

 

[pRoFiT]

oh nice build. Have you seen the cool n save product?

They use the fan to turn on/off the water. So no need for power. uses simple float valve for water control.

Was thinking about doing this as well. Let me know how it works long term

 

[Texan]

What is this? Never seen one these contraptions on a AC unit around this part of Texas.

 

[Whitetrashrocker]

What is this? Never seen one these contraptions on a AC unit around this part of Texas.

Cause we already have swamp coolers.

 

[supermanotorious]

Can you run your swamp cooler all summer? I doubt it, I imagine your weather is similar to ours, you would benefit from a system like this

---------- Post added at 05:49 AM ---------- Previous post was at 05:48 AM ----------

oh nice build. Have you seen the cool n save product?

They use the fan to turn on/off the water. So no need for power. uses simple float valve for water control.

Was thinking about doing this as well. Let me know how it works long term

I did a lot of research before I built this, saw all the options out there, admittedly, that "paddle" partially impedes the fan's output so it is likely adding a small strain on the fan's output

 

[itsid]

OMG, itsid to the rescue, ...I tried to measure AC with a DC meter...

Oh cool glad I could point you in the right direction
'sid