Posted by Tony Conner on February 16, 2000 at 09:53:59:
In Reply to: What is proper static pressure in a LP HWB? posted by Greg Oien on February 15, 2000 at 23:18:35:
: I have a Hydrotherm #R-210B LP hot water boiler and have been given conflicting information from two different repairmen. The first recommended that the pressure guage be kept at 40psi and the second 20psi.
: I have been unable to find any technical ifo on this 22 year old boiler. Thanks
If it's a low pressure hot water boiler, the relief will have to lift at 30 PSIG. That makes 40 tough to do. Unless your boiler is the basement of a building 9 storeys high, you won't need pressure like that anyway. Measure the height from the boiler to the top of the heating system in feet. Divide this number by 2.31, and this will be the minimum fill pressure for your system, in PSIG. Add a few PSI (3 - 5) to make sure it's full, and all of the air is pushed out. The circulating pump does the rest. All it has to do is provide a few PSI differential to move the water around the system.