ᐅ New heat pump to replace oil heating with existing radiators

Thank you! That helps me a lot. I sent back the DWW and didn’t sign it. Now I’m hoping for Stadtwerke Jena. They installed my photovoltaic system. Everything went perfectly smooth. They also cleaned my roof with a pressure washer as a favor. The price they quoted at the beginning stayed the same until the last electrician finished. When they install the heat pump, I have complete confidence in them. The service contract partner also contacted me by phone right away. They are located 4 km (2.5 miles) away, two towns over. In case of an emergency, they could be there within 10 minutes if a technician was available locally.

Hopefully, your system has an outdoor temperature sensor.

Yes, it does. Pipe-mounted sensors are installed on the supply and return pipes, which are easy to read. As mentioned before, the burner starts depending on the boiler temperature. I have never observed the supply temperature playing a role in this. For example, supply at 50°C (122°F), boiler at 30°C (86°F), yet the burner still switches on.

Yes, the burner maintains the boiler temperature on target. However, this initially happens independently of the flow temperature.

If the outdoor temperature results in a flow temperature of 50°C (122°F), a mixing valve blends the return water from the radiators with the boiler water to produce approximately 50°C (122°F) warm water for the flow. If the boiler water becomes too cold so that the mixer can no longer achieve 50°C (122°F), the burner has to assist. However, you never actually have the boiler temperature within the heating circuit.

On the other hand, the combustion process requires a minimum flue gas temperature for the condensing mode to work. This can also trigger the burner demand. A low boiler temperature of 50°C (122°F) may not be allowed depending on the design. Therefore, it is not a problem if the boiler has much more heat than the heating circuit requires.

Have you found the settings for the heating curve? What is currently set there?

Have you found the settings for the heating curve? What is currently set?

I didn't manage to do it today; it will be tomorrow. Thanks, tireless helper!

mixed with the boiler water

In the heating circuit for daily use (the one with the mixing valve), I have no problems. My daughter heats very consciously and never more than necessary. My son-in-law controls everything via Wi-Fi and the corresponding valves. For the apartment, I have avoided such complexity so far.

Well, it’s coming along after all. Thumbs up for that. You’re now taking the right step. The system is still running, so you can find out the lowest flow temperature. Please take some time to learn about hydraulic balancing. You can still gain a lot from that.
If you start working on this now, you can have a SUITABLE heat pump installed in the spring. That way, you would achieve something sustainable for your family and increase the value of your property. Please don’t lose patience.

A quick question for the heat pump experts. Are there heat pumps with two heating circuits, high temperature (HT) and low temperature (LT), for a combination of radiators and underfloor heating in the house? This setup exists with gas boilers.