What are the most common boiler designs available for greenhouse heating?
The cast iron sectional boiler is the oldest design and is still quite popular. It is manufactured by casting “sections” of iron The steel water tube boiler design circulates water through steel tubes. The flames and products of combustion pass over these tubes, transferring heating energy and then exit through the vent stack. The copper water tube boilers are similar to the steel fire tube design except that they use copper instead of fire tubes. Copper has a higher capacity for transferring energy and can withstand quick temperature changes that might adversely affect cast iron or steel boilers.
