ᐅ Saving Gas – Optimizing Your Control System?

We built our house 5 years ago. A gas line was installed specifically for us, which we of course paid for. We bought what we thought we could afford. Our budget was... limited.

A few weeks ago, I called the heating technician who services our system to ask what else we could do from the system side to save gas. Together, we adjusted the system settings. It turned out that the Wolf system prioritizes gas as an energy source over the solar thermal system. We couldn’t lower the minimum temperature produced by gas below 45°C (113°F) — previously it was 55°C (131°F) — and we couldn’t reverse the priority. Both settings were protected from alterations. We would accept it if, for example, the water is only lukewarm while showering sometimes, and if the boiler occasionally runs as a precaution against legionella once a week.

I am now going to contact the manufacturer to see if reprogramming might be possible. We chose the heating technician the manufacturer recommended as particularly skilled with their products, even though his travel distance is not ideal. Our bungalow is not really well suited for solar power production as it is surrounded by taller buildings.

Of course, it’s clear that the gas heating system probably won’t last long and that we will need to invest significantly. However, I don’t yet see how electricity consumption will save us.

What does the collective intelligence say? Can you optimize the controls further? What else could be improved?

Best regards,
Gabriele

Alternative 1: Factory service technicians should definitely have access to these areas and be able to correctly adjust the boiler. However, they are usually quite expensive (with my old Weishaupt oil condensing boiler, the technician came once and charged about 180€ per hour).

Alternative 2: A specialist "H" from a technical forum. The tone there is, let's say, at least somewhat challenging. However, they do provide help through sometimes endless question-and-answer exchanges.

Access information can often be found online. Otherwise, contact customer service. It is your system, and you have the right to access it.

Of course, the most important measure is likely lowering the supply temperature. Then heat continuously. No temperature setbacks or similar. Heat all rooms, with no differences greater than 3°C (5°F).

We don’t need to heat right now, but the tip is good; I’ve received the same operating instructions for heat pumps. For the supply line, I’ll have to see what’s possible.

For next winter, a good Swedish stove will be installed in the living area. When I wanted to buy it, my partner was paranoid about it. I insisted on a demonstration model. I also insisted it be purely mechanical. I only did this out of consistency—if there’s going to be an emergency plan, it should be one that works reliably. However, this will complicate the combination with the gas boiler, which also has to work together with the solar thermal system. I still need to figure that out.

The supplier has known since spring that no more stoves from Sweden will be available this year. Meanwhile, the specialist engineers no longer recommend water-circulating stoves but rather ones that operate without electricity; I occasionally have professional conversations with these experts. The stove was intended as an emergency heating system, but when I bought it, I thought it would probably only be used for fun, and I consider it money well spent for my peace of mind.

We can and will participate in saving energy as well as we can. I will miss the sauna. Or I might make it more economical by inviting other ladies to join so more people can benefit from it.

Best regards,
Gabriele

This is interesting… right now we are outside on the terrace discussing exactly the same topic with our neighbor! We have also been using a Wolf solar thermal gas boiler with a 300L (79 gallon) storage tank for 5 years. We notice that the boiler is now reheating with gas despite the solar thermal system showing 130°C (266°F). From our point of view, this doesn’t make sense! We have also set the cutoff temperature to around 45°C (113°F). During the exchange of ideas, we came up with the thought that this might be the wrong approach. Perhaps it would be better to set it to 65°C (149°F), and reheating should only start when the temperature drops below 45°C (113°F). (We hope this is programmable.) The hope is that the hot water lasts until the next day when the solar system produces again. Is this line of thinking correct?

Steffi33 schrieb:

That's interesting... just now we were talking outside on the terrace with our neighbor about the exact same topic! We have had a Wolf solar thermal gas boiler with a 300L (79 gallons) storage tank for 5 years. We see that despite the solar thermal system, the boiler is still reheating with gas. From our point of view, that doesn’t make sense when the solar system shows 130°C (266°F)! We also set the cutoff temperature to about 45°C (113°F). During our discussion, we had the idea that this might be the wrong approach. Maybe it should be set to 65°C (149°F), and reheating should only start below 45°C (113°F). (We hope this is programmable.) The hope is that the hot water lasts until the next day when the solar system delivers again. Is this reasoning correct?

I don’t know the size of your collectors. But I am confident that a well-adjusted solar thermal system should not require gas reheating from May to mid-September. At 130°C (266°F), your system is in stagnation.