How do I find the pressure in a water heating vessel at a certain temperature?

Question

I am designing a water heater and need to know what calculations I need to do before my design.

Answer 1

For you to know the pressure at a certain temperature using calculations, we have here the Gay-Lussac's law formula which is, P1 x T2 = P2 x T1; where P is the pressure and T is the temperature. Since you are using a vessel, it means you have a constant volume. This formula is the relationship of pressure and temperature applicable to constant volume.At constant volume, the higher the temperature, the higher the pressure.

Answer 2

The Keenen and Keys Steam Tables will show the various temperature/ pressure relations for water and steam. As long an the temperature is kept below 200F the generation of steam pressure will not be a problem. However you will need to provide temperatue / pressure safety valves to relieve pressures due to thermal expansion of the water and to relieve for excessive tenperatures or excessive pressures caused by the failure of control components.
If this is a school design assignment , OK, but if you are really considering building any pressure vessel, please leave it to the professionals.

Answer 3

Go to the ASME website and order a code book for pressure vessels. This should answer all your questions.

Answer 4

simple logic get a pressure cooker, but where the relief valve is put a pressure gage in to find how much pressure you have, dont forget to put water in it and put it on a burner and turn it to high.