I have a Tranquility 27 two stage 4 ton Climate Master.The black light on the thermostat is red.The screen indicates service needed phone contractor and E4-Low Water Temp.Can't get a hold of contractor.I restarted the heating system, it ran for two days then shut down again.Cleaned the filter then it ran for three days.Continuous to shut down every other day. Geo system was instaled five weeks ago.What does E-4 Low Water Temp mean on the thermostat?

My GeoMax 2 Heat Controller GSHP also this past winter went into lock-out mode due to low water temperature. By coincidence, it's the same lock-out code (4) as your Tranquility. I don't have a light on the thermo that tells me there's an error, though...I found out the difficulty way.
Low Water Temp, I believe, is same as my Low Entering Water Temp code. That is, the coolant coming in from the ground loop is below the recommended temperature for the HP to operate. If the loop isn't picking up enough heat from the ground, the HP shuts down the loop and compressors to protect them from too-cold liquids. I think my minimum is 30 F. The system should AUTOMATICALLY switch to aux heat to continue to provide you with heat, though. Is it doing this?
Also, my system will automatically restart itself every so often to see if the loop temperature is back above minimum.

The exact causes of low loop temperatures include, (and others, please correct me/add), low coolant levels in the loops, low pressure, not enough anti-freeze, malfunctioning loop circulation pumps, poor ground conductivity, incorrect loop sizes, and probably more. Unfortunately, nothing the average lay person can fix.

If your system is a closed loop. You should have antifreeze protection and your low water temp jumper should be cut. The heat pump is shutting down to protect itself from freezing the water in the heat exchanger. This is an all to common mistake from a newbie installer. If you have antifreeze and the jumper has been cut, or you have an open loop, I would suspect low water flow.

Where are you located?

I never instald the 200 amp service for the aux heat to work.Plan to this summer.I just switch the power breaker off and on to restart the system for heat.The system is a closed loop with antifreeze.Low temp jw3 jumper is cut .The system shut down at six this morning.Will use electric plug in heater to keep the house temp up through the day.Can the geo system be damaged if I keep restarting it?Ill give it a break through the day and try it tonight.Thanks for the info from central Saskatchewan Canada.

Can the geo system be damaged if I keep restarting it?


The unit is telling you something is wrong and you need to have the installer check it out.
Possible damage could occur from constant reset.
Without pressure and temperature readings you can only guess at a problem.

You need your installer.
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