Ämne: Mixing valve in the ECS 40

[triam]

Hi, apologies for writing in English, have not learned the language yet! Recently moved in the house with a Nibe F750. Noticed a very poor underfloor heating performance and discovered an incomplete ECS 40 installation (no communication connection to the pump - only power, sensors were just hanging on the wall, shunt motor lying on the floor), so it basically had no flow in the underfloor loop, everything went to the radiators on the second floor. I've put a cable through and connected it to a pump according to the documentation, attached sensors to the appropriate pipes (need to get thermal paste and aluminium tape to do it properly), now there is clearly a nice flow, but it seems that the shunt motor is missing a part and cannot be connected to the mixing valve as is. So I've found and ordered a new one, but now I also noticed that the mixing valve is connected in an other way than specified in the documentation. So my question is how screwed am I?

[Carl N]

Ops, it is correct that the radiator return is connected to the return on the mixing valve?
In that case you probably need to switch radiator return and underfloor heating return.
It might work half decent, as it is.
 
The mixing valve is otherwise correct mounted, 0 will take whole flow from return and 10 will take whole flow from heatpump to the underfloor flow.

[triam]

Ops, it is correct that the radiator return is connected to the return on the mixing valve?
In that case you probably need to switch radiator return and underfloor heating return.
It might work half decent, as it is.
 
The mixing valve is otherwise correct mounted, 0 will take whole flow from return and 10 will take whole flow from heatpump to the underfloor flow.

Thank you for the answer!

Here is what the manual says:
The mixing valve (QN25) is located on the flow line after the heat pump, before the first radiator in the climate system 1.
The return line from the extra climate system is connected to the mixing valve and to the return line from the heating system 1, see image and outline diagram.

For some reason I find it difficult to imagine how it's supposed to work. When the valve is fully open it will fully draw from heat pump to the underfloor flow, when it's closed - the heat pump will fully go to radiators? And if it's half open, then it will mix heat pump + return from radiators to the underfloor flow? What also throws me off is that the valve is mounted upside down...

[krambriw]

If I understand correctly:

- The flow to the underfloor should be mixed with the return from the underfloor
- The return from the radiators should go to the heatpump

What is the delta the pump sees with this configuration you have?

[triam]

If I understand correctly:

- The flow to the underfloor should be mixed with the return from the underfloor
- The return from the radiators should go to the heatpump

What is the delta the pump sees with this configuration you have?

5.3C right now with the valve manually open at around 5-6. I'm not sure if it's accurate though, I've temporarily attached the sensors with just an insulation tape

[triam]

Yes, that how it is now.
The valve is correct mounted, upside down is correct here.

That's great news, thank you! Then I just need to wait for the new motor to arrive, mount sensors properly with some thermal paste and it should work. It is already much more comfortable, it's keeping 21-22C on the first floor, opposed to the 18C before...

[Carl N]

Well, I have found a manual on Barberi homepage....
Maybe the valve is not correct mounted.
It seems like it close the flow to the underfloor heating when it is closed.
But you can change the valve to the right position according to the manual.

Can you move the flat part on the shaft uppwords?

[triam]

Well, I have found a manual on Barberi homepage....
Maybe the valve is not correct mounted.
It seems like it close the flow to the underfloor heating when it is closed.
But you can change the valve to the right position according to the manual.

Can you move the flat part on the shaft uppwords?

I think it's a wrong kind of valve in the document you referenced.
This is the closest I found, see the attachments. It's still not exactly same, Nibe had them custom made and I can't find any documentation for it
Seems like it's installed correctly though, but "the position of the mechanical blocking system" (black plastic thingy) on my valve is not on any of the diagrams. According to the "standard" configuration it should be on the right, but mine is pointing up.

I wonder if anyone here has a ECS 40 installed, how does their mixing valve look like?

p.s. Just got thermal paste and aluminum tape, time to attach the sensors properly...

[25fOCUS]

It is an ESBE valve you have and according to the connection it is like this. Left picture You can turn the arrows all the arrows to the opposite. Then it will be a return to the middle. And from VP at the bottom and at the top out to the floor This valve works by reversing the flow direction. Check the little black flap, which shows where it closes a gate. Do you have a motor that regulates the heat

[triam]

It is an ESBE valve you have and according to the connection it is like this. Left picture You can turn the arrows all the arrows to the opposite. Then it will be a return to the middle. And from VP at the bottom and at the top out to the floor This valve works by reversing the flow direction. Check the little black flap, which shows where it closes a gate. Do you have a motor that regulates the heat

So, if the little black flap is pointing to the flow, does it mean that:
a) when fully open, 100% goes from heat pump to flow;
b) when fully closed 100% goes from heat pump straight to return, flow gets nothing. Or the other way around: 100% return goes to heat pump, which consequently goes to the radiator loop?
c) when half open 50% from heat pump + 50% from return mixed goes to flow?

Regarding the motor, I have this guy just lying on the floor. It seems to be missing a part that allows latching to the valve. Whoever did the installation (and, for some reason, never finished) took it or previous tenants threw it away because they didn't know what it's for...
I've ordered a new one, hopefully it will arrive soon: https://www.vvsobadrum.se/reservdelar/reservdelar-varmepumpar/nibe/nibe-shuntmotor-for-honeywell-vaxelventil
I couldn't find the exact same model, but this one is matching the specification, hopefully it will work.