Heating to Slow when temperature almost reached

[oajungen 5]

I am using 10 HC's in our house for heating all rooms. Firmware 4.3 is much better as 4.0, but still much work to be done unfortunately!

 

With the latest firmware for the HC it takes very long to raise the temperature with half a degree celsius (at least one hour or even more). The valve stays to much closed when the temperature is almost reached. Due to this it takes a long time to get the temperature right. If I open the valve manualy, set to MAX, the right temperature is reached in just a few minutes.

 

I do understand the HC needs to manage over shooting, but this is to extreme! Please solve.

 

 

Edited March 27, 2018 by oajungen

[kunoch 27]

To overcome the slow and minimal temperature change for such valves (I have the danfoss LC13), I created a scene to exactly do what you do manually. I have the valves opened to the desired temperature plus 4 degrees and then lower it to the desired temperature after some time (you have to experiment as this heavily depends on the airflow and the room size and materials needing to heat up).

I would even say that 0.5 degrees temperature change is within tolerance of the valve control, so most probably the increase will not really lead to any change of the setting and if so, as you noticed, very marginal, taking almost endless to reach the minor increase in temperature. I assume the increase is only relevant, when the temperature drops below the threshold and then the valve is opened a little bit more.

[oajungen 5]

Thank you for the prompt reply!

 

I have done so for several months with firmware 4.0 because the HC's didn't open at all.

With firmware 4.3 I have removed this from the LUA scripts because I hate it to spin up and down the HC's every 10 minutes or so when temperature is needed. If this kind of behaviour is "normal" I am going back to old school heating.

 

If I could make a read out if a HC needs heating (valve is open) I could improve the scripts. With only temperature reading it is really difficult to make it work gently.

 

No I don't want to run the boiler all day

[kunoch 27]

May I ask what is the reason to have an increase of 0.5 deg only?

When I installed the danfoss(es) I observed them for several days/weeks until I found the correct temperature setting for the day for each valve in each room. At night I reduce to 18°C and heat up in the morning, together with the 'intelligent' circulation pump the normal day temperature is reached very fast.

[oajungen 5]

33 minutes ago, kunoch said:

May I ask what is the reason to have an increase of 0.5 deg only?

When I installed the danfoss(es) I observed them for several days/weeks until I found the correct temperature setting for the day for each valve in each room. At night I reduce to 18°C and heat up in the morning, together with the 'intelligent' circulation pump the normal day temperature is reached very fast.

 

I am not raising the temperature with 0.5 degree, but the temperature in the concerning room is for example at 20.4 in the morning after a night. At 6 am the schedule goes to 21 degrees. At that moment it takes to long to reach 21 (more than one hour while the room is small and radiator big enough). If I set the HC to MAX the temperature goes to 21 really fast.

 

Issue is that I keep the boiler on while the temperature of a certain room isn't at the desired level. Because of this behaviour boiler is running much to long because it takes forever to reach desired temperature.

Edited March 27, 2018 by oajungen

[kunoch 27]

OK, understood. Does your water pump in the heating system adjust the flow, based on pressure?

Mine increases the throughput, when the counter pressure decreases, means valves open, so the water flow increases and therefore also the amount of energy available to heat the radiator. but maybe danfoss has some more experience for such things as they do that already for a long time.