ᐅ Experience with Solar Thermal Collectors and Rotex Heat Pumps

Dear forum community,

In 2011, we built a single-family home in Saale-Holzland, near Jena, Thuringia. We have a Rotex HPSU compact 508 system, which is connected to two solar panels using a so-called "drainback system."

My inquiry primarily concerns our two leaking solar collectors for domestic hot water on the roof .

According to the manufacturer, these collectors are designated as T4S. The house and heat pump system were completed and installed in 2011. Now, after about 11 years, we have to conclude that the collectors are leaking. So far, local HVAC companies have refused service on the heat pump and collectors because no one is familiar with ROTEX (now Daikin).

Currently, I am seeking advice or information regarding the following questions:

• Who has had similar experiences with defective ROTEX solar water heating modules in combination with a heat pump?
• Who knows of HVAC companies in Thuringia that are experienced with Rotex systems and capable of servicing them?
• Is it reasonable after only 11 years, out of frustration with the current heating system, to consider replacing the entire heat pump system and solar panels?
• Who has experience directly with ROTEX service? (Ours has not been good, and over the past years responses were rare.)

Thank you in advance for your time and any advice you may provide.

Best regards,
Pero70

Regardless of whether the solar thermal system is still functional or not, it would make sense to dismantle it and replace the entire area with photovoltaic panels. Since you already have a heat pump, your hot water will no longer cost you anything afterward, and when it’s warm, you can use the electricity for other purposes. In an emergency, you can even sell the surplus.

Under no circumstances invest any more money into the solar thermal system.

Many thanks to Deliverer.
Sounds like it was from my HVAC company... They asked me whether I would consider switching to a photovoltaic system in the future... but they didn’t give me a reason.
There must be reasons why people are moving away from solar thermal systems, right...?
The next topic is the disposal of the solar thermal panels... Where should they go?

Pero70_15a schrieb:

But there must be reasons why people are moving away from solar thermal systems again, right...?

Produces enough hot water in summer for a whole swimming pool – but you only need a few liters for the shower. In winter, however, nothing comes from the roof. So, it's not cost-effective.
Photovoltaics produce electricity endlessly in summer – with that, your heat pump can generate plenty of hot water during the day. The rest of the electricity is fed into the grid, and you either get paid for it or use it yourself – right now I’m getting 6.64 kW from the roof, and the wall box is charging the car with it.
In winter, photovoltaics behave like solar thermal systems. But on sunny days, I still have a surplus.

Pero70_15a schrieb:

Next topic is disposal of solar thermal modules... Where to put them?

Take them to the recycling center. Private homeowners can dispose of household quantities easily and FREE OF CHARGE. They are treated like electronic waste.

Pero70_15a schrieb:

The next topic is the disposal of the ST modules... Where to put them?

I sold my three modules from ’98 for 50 € via a well-known classifieds website. They were picked up within two days.