Jack_H

The buffer probe on the ET-10 has been connected to the return pipe just before the heat exchanger - I was told this was to measure and regulate the delta t setpoint, which makes sense.

I know 😩

@HughF see the above diagram from @alfaTom - there's no internal pump, and the PWM connection is one of 5 for the pump (live, earth, neutral, common and pwm)

EcoTech Manual Version 2.1 - R32 EVI R (1).pdf See attached - I find their manuals tend to be light on detail...

Yep, I've checked and double checked the wiring...

After some help/advice - I've installed a CE-ET10. This has an an external circulation pump which wires into the controller using a PWM connection. Now the pump in question is a DUCA GEX-C Master - https://www.seconrenewables.com/duca-gex-c-master-pump---25-80-130180-8279-p.asp From what I can tell it doesn't seem to be operating in PWM mode - the pump allows me to cycle through the various modes which shouldn't be the case when operating in PWM mode (see excerpt from manual). All LEDs should be lit when in PWM mode, which hasn't been the case since I installed it. I've noticed that I'm not getting a 5 degree delta t as per my current setting (more like 10 degrees), and I'm concerned this might be something to do with flow rate, and that the fact the heat pump isn't modulating the pumps output may have something to do with this. Anyone got any ideas/experienced this issue? Cheers.

@dpmiller thanks for your response. Yeah, it always displays heating when it's on and in a heating mode (either just heating or heating + DHW) It looks like the settings are the same as the Carel ones you've described. I therefore assume when in eco mode (weather comp), the DHW settings for each of the four setpoints should be set to my desired hot water temp? Also, unlike heating which is the flow temperature setpoint, am I right to assume for hot water it's the cylinder temperature setpoint? Anyway, I've adjusted the eco settings to all be 45 degrees regardless of outdoor temp (see screenshot) - hopefully that does it

Well that didn't seem to make a blind bit of difference... DHW setpoint changed to 40 degrees and hysterisis set to 5 degrees. DHW heating cycle seemed to kick in around 40 degrees cylinder temp and went on to reheat to ~50 degrees. 🤷

Yeah, I'll give this a try and report back. Cheers

This is what I thought. My hysteresis is set to 10 degrees, however I can't see anything in the controller that looks like a differential stop for dhw...

I'm reading the temperature of the cylinder temperature sensor which is displayed in the controller and app - the sensor is halfway up the cylinder...

Hi @HughF, interested to understand how you run weather comp (fan mode = eco) but not for DHW? I have a CE-ET10, which uses a SPRSUN developed controller - settings look very similar to the Carel controller - the issue I have is, my DHW setpoint is set to 45 degrees, however the tank keeps being heated to ~50 degrees. I'm assuming it's using the weather comp setpoint, but can't quite get my head around how that works for DHW... Any advice greatly appreciated!