Hot Water & IPC Question 1

[John110]

In a project I am just replacing two hot water heaters 990 MBH /Each (for the capacity might call it Boiler). There are two 400 gallon hot water storage tank hanged from ceiling. The building is in USA and built 1998. The building is maintenance facility with partially offices. I am not seeing any main mixing valve inside the mechanical room to control the supplied hot water temperature to showers and sinks at 120F, to meet the IPC section 408.3 & 409.4 temperature requirements. I don't want to add a main mixing valve inside the mechanical room since the piping system isn't separated. This code requirement was in force during the construction of the building in 1998. Should i consider that all showers and lavatories and sinks are using temperature controlled fixtures. Since i don't have the original fixtures submittal , I have no way of finding this. The existing drawings also don't show anything related to this. Please advise.

 

[PEDARRIN2]

2012(5) IPC 408.3 is Bidets, which I doubt you have and there is no 409.4. I went back to 2003 version (oldest I have access) and still the same. So not sure which code reference you are looking.

The hot water system could be set at 120 F to begin with. If that is the case, the only thing you would need to do to bring it up to current code would be to add ASSE 1070 mixing valves at the public hand washing stations. If the hot water system has to be 140 for other reasons, you would still need to add the 1070 at the lavatories, but would also add them at the sinks. It is likely the showers have limit stops which would need to be reset if you change the temperature.

 

[bimr]

Should i consider that all showers and lavatories and sinks are using temperature controlled fixtures. Since i don't have the original fixtures submittal , I have no way of finding this.

You can verify that temperature controlled fixtures are installed with a field observation. Run the water and measure the temperature.

 

[PEDARRIN2]

Typically, during the final plumbing inspection, the inspector is "supposed" to witness such a test to verify the temperature at the fixture outlet meets code. It doesn't always happen, especially if there are a lot of fixtures to test. As part of your consulting responsibilities, it would not be a bad idea for you to do so as well, as bimr mentioned.

 

[dbill74]

If the building was built in 1998, governing version of the code of the time would of been IPC 1995. Make sure you are referencing the right version. A Quick Google search reveals that 1995 was the first edition of the International Plumbing Code, so you would need to verify that the building was even built to this this code, it may not have been if the AHJ did not adopt IPC yet.

What's the temperature of the water in the tanks being stored at? If it is being stored at 120 degrees in the 400 gallon tanks, then mixing valves aren't needed.
However, if the storage temperature is 140 or you want to raise it to 140, then mixing valves would be needed.

You don't have to repipe the entire facility to add mixing valves, just at the tanks, you can still use the same hot water distribution piping to the fixtures.

 

[John110]

Thanks for all responds.