ᐅ Disadvantage of turning off an oil heating system

Hello

energy prices keep rising, and we are now considering whether there is a disadvantage to turning off the heating completely.
We have a single-family house from the 1970s, shower briefly in the mornings, and the children take baths about twice a week in the evenings. We still have an oil heating system that switches on several times a day to keep the water warm, even when nobody needs it.

Is there a downside to introducing “bath days” and, for example, only heating the water every other day in the afternoon so that everyone can shower and bathe then? Or is the benefit not that great if the heating is off for two days straight?

I think we should save as much oil as possible over the summer because none of us knows what the winter will be like.

No, why wouldn’t that work? I do the same with our gas boiler. It only runs twice briefly a day to heat the hot water. The rest of the day it’s off. Besides, the hot water tank should be able to keep the water warm inside for some time. 🙂

I’m a bit skeptical. The energy the water loses while cooling down will have to be put back in when reheating—whether you heat it up all at once or in smaller increments multiple times. The only advantage is that energy loss is higher with large temperature differences, so moderately warm water loses less energy. However, the difference should hardly be significant in a well-insulated hot water tank.

Can you automate this appropriately with a control system, or do you have to go down to the basement every two days, turn on the hot water, and wait two hours before the shower temperature is reached?

WilderSueden schrieb:

It doesn’t matter whether you heat up a lot at once or multiple smaller times.

No, it’s not quite the same with oil boilers. It’s like with a car. Driving 500 meters (yards) three times a day is much worse (for the car and fuel consumption) than driving 10 km (6 miles) once a week. The car (the boiler) has to be brought up to temperature every time, and if the runtime afterwards is short, the percentage loss is much higher.

So yes, do it that way. How big and how hot is the hot water storage tank? If it’s 500 liters (130 gallons) at 60°C (140°F), it will probably last two days. You can experiment with that. Eventually, only lukewarm water will come from the tap, then just reheat once and that’s fine.
And turn off the circulation pump!

I still have it in my old house, where luckily solar thermal is installed.

Maybe an idea for you: Many people are currently switching from gas to heat pumps, but what do they do with the often existing solar thermal system on the roof? If photovoltaic panels are installed together with the heat pump, the solar thermal system usually gets removed... right?
Wouldn’t it be worth considering buying a used solar thermal system and possibly a solar storage tank (buffer)?
My solar thermal system usually allows me to turn off the heating completely from late spring to early autumn 😉

Unless you plan to renovate your house soon and upgrade it to a low-energy standard?

As already mentioned, we first need some numbers: the size of the hot water tank, temperature, how often does the oil burner start per day? What is the consumption during the heating period, and what is it outside of that?…