ᐅ Oil heating system approximately 25 years old, storage tank defective

Hello.

We have purchased an old house and have now found that the storage tank is defective. It is a zinc tank with an internal hot water storage.

Since we plan to demolish the house in about 5 years, I only want to invest as little as necessary. Still, heating with electricity is not an option for us. We need about 200 liters (53 gallons) of water per day.

Replacing the tank is also not easy, as it was apparently installed in the attic before the roof was covered, and the roof hatch is only about 45 cm (18 inches) wide. I have tried to draw the current condition in the attachment.

If I understand correctly, the hot water is connected like a radiator. There are no switching valves or similar devices.
Question 1: Is that possible?

Now I would like to install a new tank next to the heating system downstairs. I plan to weld a 3/4 inch connection onto the supply and return pipes and connect the new tank that way. The new tank would have a heating coil. I have one lying around — 300 liters (79 gallons) with a heating coil, a bit large but should work.

Then I would connect the central heating supply and the hot water supply in the attic and separate them again in the heating room downstairs to connect to the storage tank.
Question 2: If I do that, would the domestic hot water be warm enough?
Question 3: Since the tank is no longer positioned at the highest point, or was it placed there at that time because the heating was gravity-based?

PS: Is it still possible to buy a storage tank like the one currently installed?

Thanks for your help, I hope this information is sufficient.

Really interesting technical questions. In my opinion, these cannot be answered remotely without local knowledge. I do have a guess, though...... Choose one or two plumbing companies from the area and get advice on site. You can still discuss the results here afterwards.

Sorry to the community, I spilled apple juice on my keyboard and now all the keys are acting strangely...

Hello

even for a 25-year-old heating system, the hydraulics are quite unusual.
If you don’t want to change anything there either, it can work as you planned.

I would recommend adding a second pump and controlling it at least with a thermostat, so the heating circuit pump can be switched off during summer.

Olli

Hello.

Thank you very much for the responses.
Unfortunately, I’ve been quite busy lately, which is why I’m replying late.

I had requested quotes and talked to installers.
One wanted to replace everything for 15,000 euros, another didn’t want to do it at all...
One was willing to replace the storage tank, which wouldn’t be a problem, but wanted around 1,700 euros for the tank.

Sorry, that doesn’t work for me.

I have now removed the old tank and plan to weld shut the connections in the attic today or tomorrow and install two vent valves there.
Then I’ll weld two new branches onto the supply and return lines for the tank.
The water pipes are already reconnected.

I will build the tank sometime when I have the time.

I have also thought about adding a second pump, but that would require a lot of changes to the existing system to make space.
So now I will install an electric ball valve in the supply line to the tank.
All radiators will get an electric thermostat anyway, since we work during the day and I want it warm when I come home in the evening.
Five of them cost about 40 euros, which I think is reasonable.

Here’s my idea: I will set the thermostats so that they close all radiators around 3 a.m., for example. Then I will open the electric actuator via a timer, and the domestic hot water will be heated.
After about an hour or so, I will close the actuator again, and the electric thermostats will return to normal operation.

This way, the tank can’t be cooled down by the heating system anymore.

PS Not only the heating system is strange—just the way the house was plastered alone... I had to bring in bags and bags of filler.
But even for just five years, I want it to be as good and reliable as possible.

By the time you mentioned the manifold and the electric heating circuit valves, you clearly showed that you don’t understand your system.