Tankless Water Heater T And P Valve

The takagi gas fired tankless water heater manual specifies a pressure relief valve on the hot water outlet.

Tankless water heater t and p valve.

On the side or top of your water heater tank is a valve connected to a metal or plastic discharge tube pointing downward. Here s an excerpt from that manual. This is just a pressure relief valve i used with a tankless water heater. You shouldn t need an expansion tank on a tankless water heater.

Gas fired tankless water heaters will usually require a pressure relief valve while electric on demand water heaters may not. The t p relief valve short for temperature pressure relief valve is a critical safety device on your water heater. My personal opinion of tankless heaters is that they are way too expensive to install and maintain never mind that few plumbers know how to service them. This is one of those things that should never be needed unless something goes very very wrong with the tankless water heater.

So consult the manufacturer s installation manual. This valve may sit quietly unnoticed on your water heater but it has a very important purpose. If all goes well a tpr valve never gets used except during testing. I d check the pressure on the house before you go to the extent of changing the t p valve.

They are prone to failure particularly if there is any water condition hard water etc at all. I m betting the pressure is a little high and the act of water hammer is pushing the valve open a little. The valve is called a t p valve or tpr valve for temperature and pressure relief.