The old vacuum heating system can be enhanced today if we’ll start to think like steam but not contractors to cut installation cost.
This is side by side comparison of old and new vacuum heating concepts.
Old vacuum systems were partitioned by steam traps into pressure and vacuum sections. Steam traps released condensate into return lines, condensate flashed into vapor under vacuum – hence additional load for vacuum pump. Condensate pump pushed hot water back into boiler.
There is no partitioning in new vacuum system – it’s self-balanced under vacuum. No short circuits for vapor from boiler to vacuum pump.
No steam traps and condensate pump – condensate is returned by gravity,
In new vacuum heating system, boiler cold start in a vacuum as well. Vapor get into nearest radiator first and then into next one because it’s easiest path (pipes diameters, pressure up in warm radiator, water lock).
When all radiators are warmed up, vapor from boiler increases pressure in the system and the air in the system is pushed into return lines. At this moment vacuum pump starts again and stops when temperature at separator entrance exceeds 30-35oC. With such control paradigm, vacuum pump never expose hot vapor and overloading.
Shut off valve on vacuum line control vapor entering into radiator and can be utilized for fine heat distribution per radiators base and per raser base.
Compared to a hydronic system, the additional benefits of the NextGen VH are as follows:
Additional heat is sucked from boiler by naturally created vacuum in cooling system
Simplicity
Quick heating from a cold start, steam linear velocity in the vacuum up to 150 mph
Less dependence on electricity and moving parts
Safety – vacuum vs 30-100 psig pressure
No water damage from leaks
Copper or plastic piping for building of any height (versus PEX limited today for up to the 3rd floor)
No mechanical floors for water pumping in high rise buildings