[Tennessee_Bob]

One of the eight valves in question.

[keat]

A side view would be better but it looks like a ball valve (1/4 turn) not a gate valve.

But who cares? Getting a new valve in and out without breaking anything is what you need to worry about.

New valves are cheap.

[ThomasThomas]

That looks a plug in a tee fitting from this angle not a valve. A side view would be nice. But I know electronic stuff better. In general green is good red is bad, green pipes must mean something good if it were electronic that is.

[Lokibob]

I lived in a house like that. Valves and all.

Here is what I did. I hired a plumber and asked if there was a way to hook up the valves to thermostats. We bought the cheapest thermostats we could find, and installed them in each room. Each thermostat controlled the heat in that room only via the valve. (BTW, this was 30 years ago, too). Bet in todays world, there are computer controlled valves to do the same thing.

I loved the heat the pipes provided, and no dust but the biggest thing I liked was the floor being warm all the time.

Anyway, talk it over with a plumber and see what he/she can do.

My plumber gets $150/hour. I told him that I didn’t pay my lawyer that much, and he said “I could not charge that much when I was a lawyer”.

Let me know how you make out, I am interested.....

....Bob

[Tijeras_Slim]

I’ve seen similar valves at Los Alamos and Hanford on a gaseous diffusion system but I didn’t get to inspect them because I was near my administrative limit of 5000 mr/year and that would have pushed me over the top. Well, since your’s were installed in ‘44, they’re probably near background by now. :)