“The problem comes down to lack of knowledge and inexperienced technicians doing the job”.
People continue to be misadvised about the complexities of mixing steel rads within an existing cast iron radiator home.
Says Aron: “Most plumbing wholesalers-retailers sell steel radiators, and many of them don’t care what you have currently in your house…you ask them for a product, they provide it to you. There’s no consultation, nobody ever questions what you’re doing with it.”.
Aron continues: “You still have some installers that have never learned what the differences are between them. They will assume a radiator is a radiator, this rad has a heat emission – 2000 BTUs, and it will satisfy the room it’s in. And they’re completely right; it will satisfy the room as long as it’s got hot water. Based on the mass of the system, that might not happen for three quarters of an hour”.
A home with existing cast iron radiators often has a radiator that needs replaced, or if doing renovations, people often assume they need to replace with a steel radiator. They are forgetting two things: their radiators can be completely refurbished to look new, and that brand new cast iron is available. But without proper guidance, most people don’t know all of their options.
Adding one or some steel radiators causes an issue for the simple reason that steel releases heat way faster than cast iron. So if your home has cast iron rads, and you change the rad in your bedroom to steel, when the thermostat in your living room calls for heat, the rads will heat up. The cast iron ones will release that heat slowly, lets say over the course of an hour. The steel radiator will have heated up just the same, but will release its heat in a fraction of the time and then that radiator — and that room — is cold. It is possible to mix steel and cast iron within the same home by way of zoning, but that’s a whole other blog….
Hello,
Just came across your post while researching if is it possible to mix cast iron with steel radiators in one home. Our house has three separate zones, and the original part of our house that we are restoring completely is a square hewn log structure built in 1890 that is 437 sq. ft. This part of our overall home is its own zone and we were planning on installing 3 36″ cast iron baseboard radiators in that space. Will this work?
Thanks!
Pete
Based on square ft, heat loss would be around 17,500 btu, a Weil Mclain ci snug baseboard at 140 degree three ft long is 960btu. 3 rads give you 2880btu, your gonna need a lot of additional heat