ᐅ Setting the Heating System Correctly

Created on: 29 Nov 2016 20:57

Hello,

this is the first winter in my newly built house,
so I am starting to optimize the heating system.

I have installed the Buderus Logaplus package W22
GB172-14, G20, WU160W, RC300 package with an outdoor temperature sensor.
The house is completely equipped with underfloor heating with 10cm (4 inches) pipe spacing, triple-glazed windows, exterior walls consisting of 24cm (9.5 inches) Poroton bricks plus 16cm (6 inches) external thermal insulation composite system (ETICS).

Now my question is how to best set up the heating system, unfortunately I did not receive any instruction from my heating engineer.

Let me first give you some data.

Maximum flow temperature: 50°C (122°F)
Heating setpoint: 22°C (72°F)
Lowering temperature: heating off
Summer mode from 13°C (55°F)
Domestic hot water: 55°C (131°F)
Circulation pump switching frequency: 3/hour
Burner starts: 5247 (since mid-February)
Burner runtime: 2387 hours (since mid-February)

Service menu:

Menu 1:
1.7d. 0: no external flow temperature sensor connected

Menu 2:
2.1A: 14 kW
2.1B: 15 kW
2.1C: 2: Constant pressure 200 mbar
2.1E: 4: Intelligent heating pump shutdown...
2.1F: 0: Heating pump and 3-way valve (internal)
2.3b: Time interval between burner switch-off and switch-on 10 minutes
2.3C: Temperature interval for burner switch-off and switch-on 6 K
2.3F: Hot water keep-warm duration 1 minute
2.9F: Heating pump post-run time 3 minutes
2.CE: Number of starts of circulation pump 3 min on, 17 min off

Menu 3:
3.1A: 14 kW maximum heating output
3.1B: 15 kW maximum domestic hot water output
3.2b: 50°C (122°F) maximum flow temperature
3.3d: 3.2 kW minimum nominal heat output

These are the details I know, I hope I didn’t overwhelm you too much.

I would appreciate any advice.

Thank you very much

Mycraft30 Nov 2016 10:28

#13

You will have to ask the heating engineer, even if you are not on good terms with him. He can provide you with the information.

ypg30 Nov 2016 11:15

#14

oggear51 schrieb:
It was even set to 60 degrees before,
but I read that legionella bacteria are only killed at temperatures above 55 degrees

... what made you decide to lower it from 60 degrees when it was originally set there?

A heating system is usually pre-set by the installer as part of the handover service. It should normally work properly both in summer and winter.
You can and should adjust it individually, for example, if your daily routine doesn’t match the preset schedule or if the heating demand varies between different rooms.

The individual room thermostat in the warmest room should be set higher, and the others adjusted accordingly, as mentioned above.
Problems can arise with outdoor sensors if it’s not very cold outside yet, but you feel the need for more warmth inside.
In that case, you can raise the set temperature from, for example, 22 degrees to 23 or 24 degrees.
You generally cannot do much wrong, as long as you avoid changing fundamental settings that you don’t fully understand.
As @Bauexperte often says nicely: Never touch a running system ... or something like that.

What confuses me is the reduction... heating off.
This is about the so-called night setback, which some still use while others have stopped due to the inertia of underfloor heating systems.
We lower the temperature by 2 degrees starting at 9 p.m., and the desired temperature is restored in the afternoon. Switching the heating off would not be good!
This should also be easy to find in the user manual; for minor questions you don’t need to call your installer to discuss whether the settings are good or bad.

If your house and also your hot water for bathing stay warm, and your daily consumption is within the normal range, everything should be fine.

Edit: Unfortunately, I can’t say anything about your menu options, as I don’t access mine and I’m just a user of a gas condensing boiler.

Best regards

oggear5130 Nov 2016 11:31

#15

I hardly believe that the installer made any pre-settings; everything was still at factory settings. Especially since the maximum flow temperature was only 70°C (158°F), which is not really suitable for underfloor heating or screed.

That’s why I doubt whether a hydraulic balancing was done at all. It’s actually quite difficult to check this afterwards. You could possibly set all thermostatic radiator valves (TRVs) to 30°C (86°F) and then monitor the temperature in each room to see if they rise evenly.

Regarding the nighttime setback, it basically doesn’t matter what I set there; overnight, I might lose about 1°C (2°F) at most.

Bieber081530 Nov 2016 14:17

#16

oggear51 schrieb:
I have, of course, a gas condensing boiler with a 170-liter (45-gallon) tank. I’m realizing that a 170-liter (45-gallon) tank is actually unlikely to develop legionella bacteria since it is used up quite quickly.

This is only true if it’s constantly used for bathing, meaning the tank is functioning like an instantaneous water heater. And that probably doesn’t happen. So, more or less, water always remains in the tank.

oggear51 schrieb:
Regarding the heating system, is there any way to check if a hydraulic balancing has been carried out?

There should be a report documenting this. If not, inquire and have it corrected. If you no longer want the original installer in your home, you should find and hire another one (perhaps with a maintenance contract to motivate them to show up).

oggear5130 Nov 2016 21:39

#17

I tested by setting the target temperature to 20°C (68°F), but it still goes up to 50°C (122°F) flow temperature. I also tried it at 17°C (63°F), but it still runs at 50°C (122°F). Something is definitely wrong.

andimann1 Dec 2016 14:32

#18

Hello,

Could the heating still be running in the screed drying program? Have you checked the heating curve? For a modern house, they are often set too high and too steep.

Best regards,

Andreas

ᐅ Setting the Heating System Correctly

Reaktionen