Pentair UltraTemp Heat Pump short cycles when using RS485 remote setting

[cubicalmonkey]

Hello,
I have a Pentair UltraTemp Heat Pump 110 and a Pentair Easytouch 4 control panel.
When I enable the "remote RS485" option on the heat pump to allow control from the EasyTouch, the Heater cycle's on/off every 5-8 minutes after the water drops below the set temperature. It runs for about 5 minutes and shuts back off. rinse/repeat. It sort it feels like there's no delay so when the water hits exactly the set temperature it kicks off. When it falls below the set temp even for a few seconds, the controller is calling for heat again.

This only happens when RS485 option is selected on the heat pump. When the remote setting is OFF on the heat pump, it runs for a bit and then shuts down and seems to be more of a normal function.


Has anyone experienced this before and if so have you found a solution? Looking through the EasyTouch manual, I dont see anything that sounds like it would help my issue.
I'm pretty sure the rapid cycling of the heat pump is not a good thing for a prolonged life.

 

[cubicalmonkey]

As it turns out I was picking up noise on the temperature sensor.
I contacted Pentair support who sent me a tech bulletin showing this is a known problem and that all new control systems will come standard with a capacitor to filter out the noise.
The fix cost me $0.43 cents plus a $1 shipping so not bad.
Here's the link to the part in case anyone else happens to be experiencing the same problem.
B32529C0224J189 EPCOS (TDK) | Capacitors | DigiKey

Also attached the tech bulletin.

 

[Jimrahbe]

cm,

Excellent!!!! Thanks for the feed back as it might help others in the future...

Jim R.

 

[Perpetual summer]

Cubical, thanks for the link. I don’t have the remote, but I notice that the heater will kick the pump up to a higher speed like it’s ready to fire up and then 15 sec later drop back down. It will do this several times before the sun heats the water up a degree or so. I will have to look into this. Thanks for sharing.

 

[patterrr]

As it turns out I was picking up noise on the temperature sensor.
I contacted Pentair support who sent me a tech bulletin showing this is a known problem and that all new control systems will come standard with a capacitor to filter out the noise.
The fix cost me $0.43 cents plus a $1 shipping so not bad.
Here's the link to the part in case anyone else happens to be experiencing the same problem.
B32529C0224J189 EPCOS (TDK) | Capacitors | DigiKey

Also attached the tech bulletin.
View attachment 70074

Thank you for your post - this may be just the fix that I'm looking for for my system! Unfortunately I can't read the technical bulletin that you attached. I tried googling it, but can't find it. Would you mind please posting a higher resolution copy of the bulletin, or a link to it? Thanks!!

 

[blac1175]

Awesome, I'm so grateful for you, cubicalmonkey! I installed the capacitor a few weeks ago, and had no problems since, over half a dozen uses of the hot tub. After something like 2 years, my problem seems finally fixed!

patterrr, I started a support case with Pentair, asked for a copy of the bulletin, hoping they send me a more readable PDF that I can share here, but they never got back to me. Sorry. Let me know if you have a specific question about the bulletin, I think I managed to make out most of the contents.

Balint