When to replace heating pipes

Hi,

well, without a crystal ball no one can say whether the pipes will last another 10 years. In my parents' house, built in 1971, the original pipes were still in place when it was sold in 2012 (by the way also the original heating system, which always annoyed our heating engineer immensely. However, we used less oil with it than our neighbors with modernized heating systems...). In my parents' current house (built in 1976), the original pipes are still in place as well.

However, now the water pipes are causing problems because they are clogged with lime. But you are going to replace those anyway.

If you are turning the place into a shell anyway, I would, if at all possible, also replace the pipes. If I were you, I would not want to have to break open all the walls again after a major renovation/refurbishment in 5 years.

And you will most sensibly have to stick with an oil/gas heating system with conventional radiators. A heat pump with underfloor heating requires very good thermal insulation to be economical. That will certainly be very difficult with a house from the 1950s. If you want to bring the house up to a modern insulation standard with underfloor heating, you will probably be better off building new soon... That never pays off!

Best regards,

Andreas

Thank you very much for the answers!

It's just a pity that no one can make the decision for me.

Underfloor heating is out of the question, as there are very well-preserved, beautiful parquet floors, which will not be touched. What is definitely possible is the conversion to wood pellets.

My dream would be a heat pump/wall radiators in combination with the existing tiled stoves (wood) and possibly photovoltaics to balance out the electricity consumption a bit.

Is that unrealistic?

Hi,

Thank you very much for the answers!

My dream would be a heat pump/wall-mounted radiators in combination with the existing tiled stoves (wood) and possibly photovoltaic to balance the electricity consumption a bit.

Is that utopian?

short answer: Yes, it is utopian. A heat pump only operates effectively at the lowest possible supply temperatures. For underfloor heating, somewhere around 30-35°C. Wall-mounted radiators require higher temperatures, usually starting from 45°C upwards. At that point, the heat pump becomes very inefficient.

You would have to use special low-temperature radiators, but these are expensive, bulky, and ugly.

Photovoltaics won’t help your own heat pump initially. You need your heat pump at night in winter, when there is no photovoltaics. And the voltages/power/network probably don’t match here. Someone recently asked the same question here. I don’t remember the answer anymore, but it was something like “photovoltaics/storage provide 240 volts 2 phases, but heat pump wants 400 volts 3 phases” or something along those lines.

Best regards,

Andreas

Morning again

Did you check again? Scratched the pipe with a knife or saw blade?
In 1977, a retroactive under-plaster heating installation with steel pipe is hard for me to imagine.
Even if steel is the installed material, the dimensions of a gravity heating system are probably not, these pipes also last forever and are usable in this way.

If old valves, including thermostat valves, are still installed, you should replace them with presettable ones.

Olli

Hello Olli,
I was informed that it is steel pipe. I think I will take the risk and leave them in place. Especially because the walls in which the heating pipes run mostly do not need to be opened up for the new electrical wiring. And because the schedule suggests it.

A small apartment in the house is still occupied for another 6 months. During that time, new electrical wiring can already be installed in the rest of the house – that would at most bother the residents a little due to noise; if I were to replace the heating pipes, I would have a problem with the residents.

Thank you very much for the help!

What speaks against cutting out a part and taking a look inside the pipe? Recently, at my parents' house, we looked at the water pipe, and less than 20% of the original diameter is free from the inside.