I am remodeling a downstairs bath and converting the shower into a steam shower. I understand the relief valve has to drain into an indirect waste receptor and due to space limitations am wondering if it would be acceptable if I t off an adjacted vent stack with a p trap and vertical line similar to a washing machine drain? A floor sink will be very difficult in this location.

2 issues.

the water in the trap will evaporate over time and sewer smells will enter your home.

second, you can not by code introduce water hotter than 180 deg into a plumbing drain.

So what is the best way to drain it? The installation instructions just call for indirect drainage?

impossible to advise with out seeing what drain/s are available.

here is internet definition of 'indirect waste'.

see if it sheds any light on the question ?

Let’s start with indirect waste or an indirect drain. To some degree, the name defines its function. Nonetheless, you need context to understand its main purpose. An indirect waste is a drainage piping that runs from a plumbing fixture or appliance and discharges into a separate waste pipe or receptacle. That waste piping connects to the building drainage system. The indirect waste line is not hard piped to the separate waste piping or receptacle. Instead, it discharges by way of an air gap or break. Please see below diagram to get a better understanding of how each is piped.

The indirect waste drainage piping begins at the fixture. It is being drained to its discharge point above the plumbing appurtenance that is directly piped into the drainage system. The end point of discharge from the indirect waste must be piped above the overflow rim of the fixture. The space between the overflow rim of the fixture and the end of the indirect discharge piping is called the air gap. This air gap allows any back-up waste water to spill out over the overflow rim of the plumbing fixture without ever touching the indirect waste discharge.Let’s start with indirect waste or an indirect drain. To some degree, the name defines its function. Nonetheless, you need context to understand its main purpose. An indirect waste is a drainage piping that runs from a plumbing fixture or appliance and discharges into a separate waste pipe or receptacle. That waste piping connects to the building drainage system. The indirect waste line is not hard piped to the separate waste piping or receptacle. Instead, it discharges by way of an air gap or break. Please see below diagram to get a better understanding of how each is piped.

adding a 'standpipe' a la washing machine is a good idea

but, the relief valve discharge must NOT be inserted into said standpipe, but remain VISIBLE



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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

great idea, yes. BUT the trap must be protected from losing its seal by evaporation.

?! deep seal trap + glycerin 'fill' once a year !?

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 1 times.

1 ounce of baby oil (mineral oil) will keep the water from evaporating.