Originally Posted by aguyandhiscomputer
Someone in a Facebook group had an issue with air getting into the water filter housing and not allowing the water system to pressurize. The FR Tech Dept said the shower miser could have a bad seal and let air into the lines. I was under the impression the water miser put the rerouted water back into the fresh tank but the diagram shows otherwise.
Originally Posted by NJKris
Don't get that. The whole purpose of the thing is to re-direct water from the hot water line back into the fresh tank until the water gets hot enough to use.
Back to the fresh tank or back to the fresh tank suction line is the same thing.
Regardless, the pump is using recirculated water and not wasting fresh water by dumping it down the shower drain until the water gets hot.
The only thing putting water back into the suction line brings (vs pumping water into the tank) is the 'possibility' of having a place for an air leak on the suction side of the pump. (as mentioned)
EDIT: So, the next question is going to be... "why not just pump it back to the tank?"
Because fresh tanks can (and often are) far away from the pump and the shower.
It simply makes more sense to use short plumbing lines from the shower to the pump than all the way to the tank.
On my current 5th wheel, the fresh tank is 30' from the pump and the shower.
My pump is directly under the shower in the basement. It would take about 4' of hose vs 30' to install a shower miser in my rig.