The CRH™ label on your jetted bath heater is your assurance that your jetted bath manufacturer or plumbing professional has provided you with the 100% efficient heating technology and safety features that are exclusive to Hydro-Quip manufactured bath heaters. There are alternative technologies that claim to extract heat from the circulation pump or generate heat from turbulence in the water. The benefits of these technologies are minimal at best. The high efficiency rating, safety and performance of CRH™ bath heaters is unmatched by any alternative heating mechanisms. Insist that your new jetted bathtub come equipped with a heater bearing the Certified Real Heat™ seal; then relax.