Tundish and trap

[XanderHarris]

Are these ok to fit on undersink water heater if taking the pressure relief in to the waste pipe? A tundish and trap combined?
Mac-tun2
I can't seem to attach a picture sadly

 

[dilalio]

Are these ok to fit on undersink water heater if taking the pressure relief in to the waste pipe? A tundish and trap combined?
Mac-tun2
I can't seem to attach a picture sadly

Is the heater new? Still under warranty?
If so, ask the manufacturer.

 

[Fredstudio]

.

 

[Madrab]

Wouldn't see why not, as long as it certified to take the temps that may be released under fault conditions. It does state that it is designed to be used with, amongst other things, water heaters and PRV valves

 

[Rodders53]

Tundish with Self-Closing Valve

Upgrade your tundish setup with the Tundish, featuring a Self Closing Valve for efficient water flow and prevention of backflow.

mcalpineplumbing.com

100 Celsius rating would worry me slightly as the PRV could potentially allow super-heated water to escape initially? Perhaps... But that may only be in a double fault condition?
@Madrab as a pro with the right experience may have a view?

 

[dilalio]

Tundish with Self-Closing Valve

Upgrade your tundish setup with the Tundish, featuring a Self Closing Valve for efficient water flow and prevention of backflow.

mcalpineplumbing.com

100 Celsius rating would worry me slightly as the PRV could potentially allow super-heated water to escape initially? Perhaps... But that may only be in a double fault condition?
@Madrab as a pro with the right experience may have a view?

Are you G3 qualified?
Doubt it.
As I said above... If it's under warranty or new install, you have to follow MI's.
If not and your own place... Pretty much do as you wish.

 

[denso13]

Are these ok to fit on undersink water heater

Which heater?

 

[Madrab]

PRV's in that instance usually let go at a certain pressure as they are there to protect against excess expansion and they are usually located on the cold feed downstream of the heater, so super hot water isn't normally an issue - TPRV's are the ones that let go at specific high temps and usually at a much higher pressure but even then they usually go @ around 95Deg, so usually prior to the water getting over pressurised and then superheated and/or turning to steam.

As suggested by @dilalio, MI's trump all and that's where it is defined as to what should be used. All l would say is that the McAlpine tundish is the same material and design as any other normal tundish used in these scenarios, so it's tolerances should be the same, only difference really is that it has a self closing one way valve to stop sewer gases escaping.

If the MI's ask for a tundish, as suggested, then this would probably be ok, I presume this is a <=10/15L unit and no larger?