Q: I’m doing a remodel on a home that is currently heated with steam radiators. The boiler is fairly new, but I’m wondering if I should stick with steam or convert to hydronic? And if I do keep the steam system, should I upgrade to newer radiators or keep the old, bulky, but classic-looking ones?
A: Keith Cappuccio, a licensed plumber in New York City, responds: Steam is a time-tested method of heating a home. Although it’s not as versatile as hot water (hydronic) heat, when installed correctly steam should provide decades of relatively maintenance-free operation. When asked about the feasibility of converting a steam system to a hydronic one, I usually point out the following items for general consideration.
First, many steam systems are one-pipe systems, with only a supply pipe and no return, so it might not be possible to re-use the existing steam pipes to circulate water through the house. Running new pipe would not be a problem if you are gutting the home’s entire interior. If you aren’t, though, you can anticipate having to remove and refinish a significant amount of plaster and trim to run those new lines, even though trusted PEX brands can be fished through the house more easily than the copper pipe of 20 years ago.
Next, hydronic systems use more pumps, valves, and relays than a steam system, so maintaining a hot-water system over the years may prove to be more parts-and-labor intensive.
But hydronic heat has its benefits. It is very versatile and can be used for radiant, baseboard convectors, or freestanding radiators—all in the same system. Plus you can combine a solar water heater with the boiler for a super-efficient design.
My advice? If the work you’re planning to do is more cosmetic, stick with the present steam system. If the house will be gutted, however, consider re-using the boiler block as a hot-water unit and install a radiant manifold with 3/8-inch PEX lines traveling individually to each radiator. The supply manifold includes balancing valves to control the temperature of each heating circuit. You’ll get a classic look, while saving money on radiators and a new boiler.