Solar yield is not readable

We have a small solar thermal system on the roof. This was absolutely necessary because we have a gas heating system (heating station with storage is from Fa. Wolf). We finally wanted to know how effective our system actually is. At first, we thought we were just too dumb to find the values on the display. After a lot of back and forth with the heating company, it turned out that our system does not have a "Wärmemengenzähler". "The system only saves about 5% anyway. And besides, we only installed all this because the legislature requires it," was the statement. I'm baffled now... This is the first time I've heard that. We paid quite a bit for it but cannot verify at all what the system delivers? Is this common???

How is it with you? What do the solar collectors achieve? Can you read out your "Wärmeertrag"?

Best regards Steffi

"The system only brings 5% savings anyway.

But even those should, in my opinion, be based on knowledge rather than belief. I find the statement pathetic – any laptop can quite accurately say how long its battery still has power. That should also be possible in today’s rocket technology heating boiler with just a cheap component.

Good morning

Not all solar controllers allow the yield to be read in kWh.
For those that do, it is only as accurate as the settings are correct.

As a rule, a heat pump for the residential unit should not run from May to September.
Except during bad weather periods.

Much more important than knowing how many kWh are saved is to use the system as efficiently as possible.
This means, for example, scheduling the dishwasher and washing machine to run in the afternoon, thus cooling the solar part of the storage tank and enabling further use of the collector.


Olli

Moin Moin

Not all solar controllers allow the yield to be read in kWh.
For those where this is possible, it is only as accurate as the settings are correct.

As a rule, a domestic hot water heating for the residential unit should not run from May to September.
Except for bad weather periods.

Much more important than knowing how many kWh are saved is to use the system as efficiently as possible.
That means, for example, using the dishwasher and washing machine in the afternoon hours, cooling down the solar part of the storage tank with that, and enabling further use of the collector.


Olli

But solar thermal supports the heating...??

We also have a gas heating system...and I’m glad we didn’t put solar panels on the roof...in summer when the yield is greatest, I hardly need any power...since from May to September I only consume about 80m³ of gas...that’s then 40-50 euros...?

I don't see anything wrong with that. This is how it is done in the vast majority of cases. A standard regulator from the [Heizi] is installed, which usually only allows you to read the temperatures.

Everything else is a special feature. In other words, it costs extra.

For example, to schedule the use of the dishwasher and washing machine in the afternoon hours, thereby cooling the solar part of the storage tank and enabling further use of the collector.
Olli

In the past, I considered what it would be like if the washing machine and dishwasher were generally supplied with warm water to save heating costs (gas instead of electricity), although cold water should not be dispensed with here, e.g., if one wants to wash clothes with cold water. After researching, I found out that not every washing machine or dishwasher is suitable to be supplied with warm water. Was I misinformed or do you own such devices?

Now the following is stated in our contract for our construction project:

Should I pay attention to anything special?

My colleague who already built a house with a solar system on the roof also said, "From May to September, solar warm water is enough for me to shower."

I am now wondering, to better understand whether solar runs effectively, is it allowed to turn off the heating during this period?