System:  Heat Controller GeoMax 2 (Climate Master rebrand) -2 stages, variable speed blower fan.  Honeywell Zone Board ZP432 and 2 zones with Honeywell VisionPro 8000 thermostats.

Last night I noticed the fan/system was blowing at maximum cfm and I figured it was meeting the needs of one of the zones.  This morning, the system is still blowing at maximum cfm but both zones are satisfied...they are both at or below their set temperatures.  Also, the fan setting on each thermostat is set to "auto".

My wife tells me that while she was up in the night with the little one, the system was still blowing air like crazy all night.

Switching both thermostats from "cool" to "off" made the fan stop, but switching it back to "cool" makes the fan go on full blast again.

Right now, I've pulled the breaker for the system to allow it to reset completely.  We've had some bad t-storms in the area (I think one killed my WELserver). 

I was planning on:
Setting both thermostats higher than room temperature to start, both to "off" and both fans "off"
Turning on the breaker to turn the system on again
Switching zone 1 to "cool", keep fan on "auto" and observing
Then try Zone 2 to "cool", keep fan on "auto"
Turn temp down for Zone 1 so system activates
If operation seems normal, do the same for zone 2

how does this sound?

U can try it but my hunch said if the fan still runs when thde power is restored you need help.

Step 1
I unplugged both thermostats from the walls, then restored power to the geo unit.

I overrode the purge since the system has been "unplugged" for about 2 hours.

The fan did NOT come on.

I'll wait a bit and see if it does by itself without any thermostat calls. I'll also monitor the zoning panel.

UPDATE #1
Fan has not come on, so I plugged Zone 1 Thermostat back into the wall.  Set to FAN"Auto" and System "Cool".  Thermo setpoint is 78F,   inside temp is currently 76 so no call being made.

Fan remains off.

Update 2

Was out most of the day. Came back to a hot house. When compressors engage it's only for a few minutes then they shut off, even though zoning panel indicates cool 1 and 2 being called.

System is calling for cooling 1 and 2. Compressor activates for a minute then shuts off. A little while later, it activates again for a minute then shuts off. It keeps doing this with no error code on the cxm.

Last data I had was EWT of 85, loop pressure on the p/t port (system off) was 13 psi.

I don't know CM's boards or error codes, and it is really difficult to diagnose from afar, but operation for a few minutes and then cut-out in cooling mode is consistent with a loss of water flow.

If water flow stops completely, thermometers on Pete ports will not see the temperature rise going on in the coax.

A couple minutes is all it takes for the hot gas to warm the coax and water within it, following which refrigerant pressure spikes and compressor interlocks on high head or high current.

I would expect such a condition to throw a code since it is a fairly fundamental failure, so it may not be the case here.

Thanks Curt and Joe,
I'm waiting to hear back from my geo guy today. Fortunately, it hasn't been TOO hot in the area lately, although none of us slept well last night...just plain humid.

I'm leaning towards the C(X)M board being bad at this point. The manual for the geo says that if there is a fault, the unit will try 3 times to operate then lockout from further attempts and signal an error code. My system isn't stopping its attempts after 3. It just keeps trying for hours and hours, running the compressor for a minute every five minutes or so. There is flow in the ground loop (the gpm gauges show about 11 gpm total).

It's funny, too. Right now the t-stats are set to System Off, but I have the Fan On to circulate air. And the blower motor keeps ramping up for a minute, then going back to low speed for a while, then ramping up fast again for a minute.

I'll post the solution when it gets fixed.

Do you have a Comfort Alert module inside the geothermal cabinet? If so, it might show an error code if the unit is not reset after multiple compressor attempts to start.

No, but they sound cool!

I took the cover off of the electronics sects of the geo so I could see the cxm boards etc. apparently the cxm led blinks on lockout and then shorting the test pins makes the cxm blink the error code. The cxm is not blinking, and shorting the test pins give a code of 1 which means, "no error code in memory" LOL.

So no luck there.

My WEL stopped working around the same time (it's dead) which leans me towards the power surge/static spike or something.

Turns out the zoning panel was sending a faulty call for emergency heat to the equipment.  Disconnecting the wire for the E call fixed the system for now while a new zoning panel is ordered.  And the panel is under warranty.

If the unit has a two stage Copeland compressor it likely has the comfort alert module.

Good catch on the E-heat