Tankless Water Heaters/pressure relief

[clinktone]

Are tankless water heaters required to have a pressure relief valve of some sort since there really is no pressure to really worry about since there is no tank?

[DUNBAR PLUMBER]

Yes.


Any time you create thermal expansion in a potable water system, there must be a safety device that allows the device to safely discharge, whether pressure or temperature.

[GregH]

I agree with Dunbar.
There really is a tank on a tankless but is is only slightly larger than the elements if it is an electric one.
The use of a temp/press reilef is even more important on a tankless because it takes so little time to heat the water if something went wrong.

[clinktone]

I have the usual 40 gallon gas water heater now, and I know where and how the pressure relief valve is installed there, but how do you install one in a natural gas tankless model? There doesn't appear to be a way to do it. Do you install it in the line before it enters the tankless water heater?

[DUNBAR PLUMBER]

They used to install those on the hot side outlet coming out of the tank by means of a tee.


Be more specific on the model you have. Post a PDF instruction/spec sheet of the model you have.

[clinktone]

http://www.omega2000group.com/product_info.php?products_id=50

Omega 412

This is the website that would have the info that you might need to help me with. I certainly appreciate your assistance.

[DUNBAR PLUMBER]

Here is the only thing that I was able to come up with, in relation to the device and protective measures:




The water intake is fitted with an overpressure release valve and a screen filter, both of which protect your investment.




I have no experience with this device, so I do not know if there is an additional line that connects to release valve or not.






By the way, that unit you are purchasing has only a 3.0 gpm max flow........and they CYA by saying "two legal showers, both of which are tempered by cold water will be able to be ran."


So, consider that if you have the situation where you take a shower the same time the washing machine is running. You are taking that unit to its maximum use, which in most cases would indicate that you are using the device that is undersupplying your needs.



Consider a unit with a higher GPM rate, especially if there is more than 1 person at the home.

[clinktone]

I noticed their flow rate also, but with only three people in the house, we rarely run two appliances at the same time anyway. We're able to work around the multiple use-at-the-same-time concern. I appreciate your responses; they were very helpful.