Willits

Thanks for the feedback. I will do a flush through out and have some x100 inhibitor on the way to add and will get some biocide to add as well. I have an bench top ultrasonic cleaner and will try to get the sensor extra clean using that.

Yes it’s a series 4 and I do have a mag filter fitted. I pulled it out once and cleaned with rubbing alcohol and a tooth brush. Its right in the middle of the body and the easiest to get to. That’s why I tried the F3 hoping it would get into all the hard to reach areas.

I have a DHW loop but turned it off to be sure it was not the mixer valve. The flow goes straight through to buffer tank without any potential restriction points. So if there is a restriction it has to be in the heat pump. I think the thing to do is to confirm the actual flow so I can decide if the flow sensor is suspect or not.

Thanks, I did read that thread before posting, and did some of the checks which did not make any improvements.

Hi all, I’m hoping to get a bit of insight on a CH014 flow error I’m seeing on my LG Therma V 9 kW monobloc. I use both heating and cooling and it behaves perfectly in cooling mode. In cooling mode, there are no errors at all and the reported flow sits steadily at around 31–32 l/min. As soon as I switch over to heating the unit starts up normally and will run for 10–15 minutes, but once the flow temperature gets to around 25 °C, the displayed flow suddenly drops (sometimes down to ~5 l/min) and it throws a CH014. It then shuts down for about a minute, restarts, runs for another 5–6 minutes, and repeats the cycle. A few things I’ve already checked: The circulation pump seems fine. The system has a 4-pipe buffer tank, so I don’t think this is a downstream restriction issue. In pump-only / no-load operation (cooling mode with no demand), the flow is stable all day. The flow sensor itself is a Sika vortex-type sensor (no moving parts). I took it out and cleaned it — it was coated in a very fine black film. After cleaning it did improve slightly, but the fault is still there. I’ve now added Fernox F3 and am circulating it to see if that helps. What I’m struggling to pin down is whether: the unit is really losing flow once heating starts, if the flow sensor is reading false once the water warms up, or maybe something different entirely. I was going to just replace the flow sensor to see if that solves it until I found that they are more than €300 from Sika and closer to €500 from LG. So before swapping it out I’m considering fitting a temporary external flow meter just to confirm whether the real flow is actually collapsing or if it’s a false reading. Has anyone seen CH014 only in heating or had experience with vortex flow sensors drifting or failing when warm on Therma V units? I’ve searched through the forum but haven’t found anything that quite matches this behaviour. Any thoughts very welcome — thanks in advance. Peter

Hi Reed, That is a good point. I was thinking that the heat pump provides 220 and switching on and off according to the program. That is how the how the 3 way valve is running. But the connections acting as a switch makes sense. I'll check that tomorrow. May thanks.

Hi Reed, I fully agree, I can achieve the circulation with an external unit. I was trying to take advantage of the built-in function for the DHW circulation since it is there. Everything is connected as per the manual and the only issue is it is not turning the pump on and off. i.e. not supplying power to the terminal block connection points for the pump. Thanks

Hi John, What I am not finding is a way to set the circulator pump to on so I can check if the terminals receive power. The only thing I could find is the DHW recirculation on/off cycling setting. Which I am guessing when set should enable the power to the pump but in my case does not. Indeed the manual states series 3 models don't have the option but the series 4, which is mine, does.

If I can't get the ASHP control to work that is my plan. I was trying to avoid adding another piece of equipment. Especially since the function and connection point is already there.

Hi Dave, I am fairly sure the manual I'm reading is for the monobloc I have. All the other terminal connections matched up with the unit and manual and worked as expected. The issue is exactly that there is no power being fed to the pump. It is a new installation and pump has not yet worked. I did direct wire the pump to a socket to make sure it works and it does. There are no errors shown on the controller. I did not find an option on the controller to test run the circulator pump. Thanks again.

Hello All, I have a Therma V 9kw monbloc installed with a DHW tank and recirculator pump. All is working as expected except the recirculator pump is not coming on. DIP switch #2 is off and #3 is on and the pump is connected to TB1 terminals 19 & 20 - water pump C. In the DHW menu recirculation time is set to “use” in the controller (for now I have set it at 60 minutes on and 5 off so I can see if it is running). My pump is a Grundfos Alpha 1L which uses a maximum of .26 A. I must be missing a setting or jumper somewhere. Does anyone have some advice what else to check? Many thanks, Peter