See photo...FLOAT SWTICH QUESTION FOR THE HVAC EXPERTS - InspectionNews

Gene South · #1 (**permalink**) 03-18-2010, 04:17 PM

I have seen some older float switches that immediately shut down the unit when tested by lifting the float. Today I saw paired two AC units with the same brand of "Electrical disconnect" (Do not want to call it a "Float switch" since it may not be designed to "Float" but rather to "detect" water.

Anyway, these switches had a movable shaft that I lifted and held up for a minute. Neither AC unit was interrupted and contined to operate.

See photo. Does anyone know if these devices are "water detectors" or float switches"?? Went to the website and the specs did not really say how it worked. Should they shut off when I left the small sliding shaft?

By the way, these were brand new units in a brand new home.See photo.

Jerry Peck · #2 (**permalink**) 03-18-2010, 05:00 PM

They may have shut the outdoor unit (condenser unit) off and not the air handler.

Gene South · #3 (**permalink**) 03-18-2010, 05:22 PM

Hi Jerry, the condensers stayed on. Full system stayed on.

David Bell · #4 (**permalink**) 03-19-2010, 04:38 AM

The switch is not wired correctly, or no good. I wire them to break r so it shuts down the whole system and the homeowner knows there is a problem. I use those often and have yet to have a problem with any of them. I like them because the float height is adjustable to the pan depth.

Phil Brody · #5 (**permalink**) 03-19-2010, 05:02 AM

Agreed, probably not wired right, but isn't any real water in the pan a sign of a problem ? Why not a wet switch ?

Jess Alvarez · #6 (**permalink**) 03-19-2010, 05:07 AM

A sign of a problem is when there is water in the overflow/emergency pan!

David Bell · #7 (**permalink**) 03-19-2010, 05:12 AM

I prefer float switches to sensors especially in attic installs.

John Arnold · #8 (**permalink**) 03-19-2010, 05:44 AM

Is there any problem with testing floats like this by hand? Does the AC equipment care if you shut it down and then back on again quickly, or repeatedly?

Wayne Carlisle · #9 (**permalink**) 03-19-2010, 06:51 AM

Only when the AC is on. It puts a strain on the compressor and the compressor won't kick on until it has been off long enough so that it won't overload the breaker.

Don't know about the heat strip on an electric heater though...

John Arnold · #10 (**permalink**) 03-19-2010, 09:17 AM

Quote:

Originally Posted by Wayne Carlisle

Only when the AC is on....

Well, isn't that when you'd be testing the float? When the AC is on?

Wayne Carlisle · #11 (**permalink**) 03-19-2010, 10:25 AM

You could test it with the heat on!

Phil Brody · #12 (**permalink**) 03-19-2010, 02:01 PM

You can't test it with the heat on unless it's a heat pump. The unit can be legitimately wired to disable only the compressor. If the unit utilizes heat strips it won't effect functionality.

David Bell · #13 (**permalink**) 03-19-2010, 02:17 PM

When wired to break R you can test it in any mode. I use these in 95% direct vent horizontal furnace installs also.

Phil Brody · #14 (**permalink**) 03-19-2010, 02:35 PM

But not everybody wires them to break R, most I know interrupt the condenser and break Y. If the condenser continues to run with the switch activated there is a problem.

Dom D'Agostino · #15 (**permalink**) 03-19-2010, 02:54 PM

Quote:

Originally Posted by Phil Brody

But not everybody wires them to break R, most I know interrupt the condenser and break Y. If the condenser continues to run with the switch activated there is a problem.

The manufacturer of that secondary float switch specifies that the unit is be connected to R. I know some will wire it another way, but hey, that's what it says...

http://www.aquaguardusa.com/index.ph...id=140&lang=en

Dom.

David Bell · #16 (**permalink**) 03-20-2010, 05:50 PM

Just as a sidebar, the condensate does not seem to be trapped before the tee connecting the pan drain. I can't tell from the picture whethter that is the primary or secondary drain but it should not be piped directly together without a trap.

Jerry Peck · #17 (**permalink**) 03-20-2010, 06:20 PM

Quote:

Originally Posted by David Bell

Just as a sidebar, the condensate does not seem to be trapped before the tee connecting the pan drain. I can't tell from the picture whethter that is the primary or secondary drain but it should not be piped directly together without a trap.

What I think you are looking at, at least what I think I am seeing, is:
a) primary condensate on left which goes to a tee (with a clean out up? hopefully it is not a vent up) then down to ??? (a trap would be correct)
b) secondary condensate on the right which goes to down to a trap (hopefully, I see something behind the foam insulation)
c) drain from auxiliary drain pan
d) moisture detector switch of a float switch style

Hot Dang! That install at ALL the goodies!

Jim Luttrall · #18 (**permalink**) 03-20-2010, 08:14 PM

Quote:

Originally Posted by David Bell

Just as a sidebar, the condensate does not seem to be trapped before the tee connecting the pan drain. I can't tell from the picture whethter that is the primary or secondary drain but it should not be piped directly together without a trap.

Yep, and it is hard to tell from the picture but it looks like they have the primary drain vent pipe ahead of the trap which will waste air into the attic along with the secondary that is tied into the drain pan line. In short, there is a bunch of air leaking into the attic and it needs to be fixed with properly positioned traps and drain line vents.

Jerry Peck · #19 (**permalink**) 03-21-2010, 11:05 AM

Quote:

Originally Posted by Jim Luttrall

Yep, and it is hard to tell from the picture but it looks like they have the primary drain vent pipe ahead of the trap which will waste air into the attic along with the secondary that is tied into the drain pan line. In short, there is a bunch of air leaking into the attic and it needs to be fixed with properly positioned traps and drain line vents.

Unless that is a: (bold added for highlighting)

Quote:

Originally Posted by Jerry Peck

What I think you are looking at, at least what I think I am seeing, is:
a) primary condensate on left which goes to a tee (with a clean out up? hopefully it is not a vent up) then down to ???