Climatemaster tranquility 27 help!!!!

[michael07311988]

Good afternoon everyone. I have a climatemaster tranquility 27 ttv026 heatpump. This was a very slightly used unit I bought. I did see it working perfectly before. I have it now installed in my house with a SCW setup. My issue is I get a lockout Unless the leaving water temp is atleast 16 degrees higher then the entering water temp. I can get it to work perfect with a ball valve on the return side. But I am trying to get it to work with a dole flow regulator. I have 3/4 piping feeding and returning. With a SCW setup this unit is at 28,100 btu which is 2.4 tons. So according to climatemaster I need 1.5 to 2.0 gpm per ton which means I need a flow regulator between 3.6 and 4.8 gpm. I installed a 24vac NC water valve today and the dole 4.00 gpm flow regulator. My issue is I have a entering water temp of 66 degrees and a leaving water temp of 71 degrees. I need a 20 to 27 temp difference from inlet to outlet water temp from what I read on the install manual for open loop. I can't figure out why on earth the 4.00 gpm regulator would not let the water warm up enough. 4.00 gpm is within spec but the unit will run for 3 minutes and then shut the compressor off. I had this issue before with a ball valve but I closed it a little to dial it in and could get it to stay running and get my temps right. I could just use the ball valve but I had no idea how many gpm I was flowing. Climatemaster said its important to be around 1.5 gpm/ton. Which is why I changed over to a flow regulator. Is something wrong with my unit? Also when it does work correctly with a ball valve I am getting 18 degree cooler air from supply vents compared to return vent temp which I believe is normal. Thanks for any help.

[michael07311988]

Nevermind. Bad fp1 sensor. I have the same unit downstairs and i swapped the sensors and fixed it upstairs but now have the issue downstairs. Im just going to order 2 of the new updated fp1 sensors. Figured I would post this encase anyone else has similar issues. Fault code was 4. Thanks.

[Pres1227]

What does fp1 sense? Also just thought I’d add that you could have stuck with the ballvalve and just read your pressure drop across the heat exchanger. That’s how you find your gpm. I actually just had an instructor/local rep tell me to dial back with a ball valve to get the right delta.

[GorillaTight]

Been a while since I've seen a geo, but I think fp=freeze protection located on the evap coil.