Modern Radiant History

Radiant heating has had vast improvements here in the U.S.A. thanks to knowledge gained from the European market. 70% of all new heating systems installed today in central Europe are radiant. PEX tubing and outdoor reset with constant circulation have made modern radiant systems much more durable than the older systems from the 50’s and 60’s. European PEX systems have been in the concrete slab for forty years now can last up to 200 years in concrete.

Radiant Heating has come a long way since the 1950 and 60’s. A lot of radiant systems were installed in the United States back then. These older systems are mostly copper. Interest in Radiant heating died out in the 70’s here in the United States. The copper reacts with the cement and corrodes. The copper expands and contracts in the cement. Sometimes the cement cracks and the copper breaks at the cracks. A lot of these systems leaked and were removed. This destroyed the American confidence in radiant systems.

Over in Europe the people didn’t have these same problems. Radiant heating is flourishing over there. The technicians are better trained in Europe. A hydronic technician is considered to be an engineer. The systems functioned better in Europe than they did in the United States. In central Europe more then 70% of all new heating systems are radiant. The Europeans have greatly advanced the technology. The European systems are extremely comfortable, long lasting and save money on fuel bills.

A few technicians started to look at the European systems. They started to copy their methods in the 80’s. Slowly radiant heating started to make a come back here in the United States. People watched This Old House. Richard Trethewey installed many radiant systems on This Old House. In 1994 the Radiant Panel Association was started and JR’s Plumbing & Heating was one of the first companies to join in Connecticut. Money was raised and research and development started. A German translator was hired. The Radiant Panel Association began to put on trade shows and teach seminars. Radiant heating is growing in popularity very fast here in the United States now. Today we have learned a lot from the Euopeans and we have developed some new techniques of our own. Now the Europeans are learning a few things from us.

The largest improvement in radiant heating is PEX pipe. This form of plastic pipe is not new. It has been around for 40 years now. The Europeans have been using it for many years. A study was done and some forms of PEX have a life expectancy of 200 years. Pex doesn’t react to the cement like copper does as PEX expands when cement cracks. PEX can stand up to corrosion much better than copper. Wirsbo has produced enough PEX pipe to wrap the world at the equator more then 16 times. Wirsbo PEX has been in radiant heating systems for more then 30 years now. Not one foot of Wirsbo PEX has failed due to wear and tear. At JR’s Plumbing & Heating, we have been to the factory and are trained in using Wirsbo products. Many other products and techniques have been improved upon for radiant use too.

If the old copper systems were properly installed and well maintained over the years they can last almost forever. Some copper radiant systems are 70 years old and never had one leak. Mixing a proper batch of cement could have stopped corrosion and saved many of these systems. Running lower slab temperatures and constant circulation will greatly reduce the wear and tear on these older systems. A properly maintained copper radiant system can last for years. Many technicians lack the knowledge to install radiant systems. The average technician doesn’t understand the difference between a radiant system and a normal hydronic system. A hot water baseboard or radiator system runs with a water temperature of 160- 210 degrees. 150 degrees will crack the cement of a radiant heating system. Radiant systems run with water temperatures of 90-140 degrees in the slab.