ᐅ Heat pump – about 60 cycles per day

Hello, our Elco aerotop Split 07 air-to-water heat pump cycles on a 30-minute interval. A hydraulic balancing has been carried out. Additionally, I have disconnected all ERR valves and removed the actuators. I performed a thermal balancing to the best of my knowledge. However, the longest heating circuits were not fully opened during this. I suspect the heat pump is oversized, which might cause it to overheat. The heating curve is already set to the minimum. I have attached a picture noting all data from the last week. From this, I also gathered that the heat pump currently cycles every 30 minutes. Furthermore, the flow rate remains the same whether the pump is running or not. It must have been cycling since installation, as it has over 10,000 cycles recorded after 2 years. I suspect this is all related to the settings. Therefore, I list below some settings and general data.

146 sqm (1,575 sq ft), 2 persons, single-family house, no basement, underfloor heating, ventilation system with heat recovery, photovoltaic system, insulation practically KfW 40 standard (without subsidies).

Heat pump operation: eco plus
Flow temperature correction + 2 degrees
Pump operation modulating
Max pump PWM 100
Min pump PWM 70
Domestic hot water 48°C (118°F)
Domestic hot water target minimum temperature 43°C (109°F), heated only at midday
No night setback
Silent mode enabled (power reduced to 70% for noise reduction)
Bypass valve open as shown in the picture
Heating curve 0.2 (range 0.2 to 1.0)

Buffer tank:
Buffer charging activation: off (should it be?)
Buffer tank hysteresis 5°C (9°F)
Storage target temperature 40°C (104°F)
Buffer charging type set to partial charging
Buffer heating hours: 0 (almost 2 years)
Buffer charges: 0
Buffer temperature 23°C (73°F)

During operation, the system shows the following values. As I have already been told, it is strange that the hot gas temperature is so low.

Evaporator temperature 0°C (32°F)
Suction gas temperature 2°C (36°F)
Hot gas temperature 28°C (82°F)
Condenser 24°C (75°F)
Compressor 23 Hz
Speed 625

What can be adjusted here, or is a technician’s inspection unavoidable?

Below are my heating circuits with their lengths and current flow rates. In parentheses are my settings from last winter. Why have the flow rates changed so much (especially on the upper floor)? Is this due to the heat pump settings?

Ground floor:
WC 49 meters (161 feet) flow 1.0 (1.0)
Office 59 meters (194 feet) flow 1.3 (1.5)
Hallway 45 meters (148 feet) flow 0.5 (0.6)
Utility room 40 meters (131 feet) flow 0.4 (0.4)
Kitchen 84 meters (276 feet) flow 1.0 (1.1)
Living right 89 meters (292 feet) flow 1.9 (1.6)
Living left 106 meters (348 feet) flow 1.7 (1.6)

Upper floor:
Bathroom 100 meters (328 feet) flow 2.6 (1.9)
Child 1 103 meters (338 feet) flow 1.1 (1.4)
Hallway 16 meters (52 feet) flow 0.3 (0.6)
Bedroom 67 meters (220 feet) flow 0 (0.5)
Dressing room 34 meters (112 feet) flow 0 (0.6)
Child 2 88 meters (289 feet) flow 1.5 (1.4)

Close the construction supervision if you have deactivated the energy performance certificate (EPC)...

Alessandro schrieb:

close the main valve when you have deactivated the ERR...

Today, I turned it all the way to the right to increase the triggering pressure. I will see if that helps. I have just noted the cycling rates.