Seeing jurisdictions announce 2024 IPC adoption in January, I’m tightening scald-protection checks on residential finals. I’ll be verifying ASSE 1016/1070 listings at tubs and showers and recording a max 120 F at the outlet with a calibrated digital thermometer, along with confirming cold-to-hot orientation and safe shutoff. Anyone else updating their checklist or noticing common misses as this rolls out?
I’ve had better consistency if I catch the stream in a small paper cup and stick the probe from my “calibrated digital thermometer” in the cup, then log the 120 F from the stabilized sample. Only caveat is tankless units can ramp, so I let it run about 45 seconds first so the cup reading isn’t low.
I run the shower full hot for a minute, then have someone flush a toilet to see if the pressure-balance still holds under “120 F” — my cheap stress test. If there’s a recirc loop, I recheck after the pump kicks on; I’ve seen a couple creep to 122–124 even with ASSE 1016 valves. Handy on-site lookup for 1016/1070 listings: https://www.asse-plumbing.org/Directories.
I photo the ASSE 1016 stamp, set the limit stop to ‘120 F’; IR guns lie on water.
On homes with recirc or tankless, I log the “first‑draw spike” at the shower before it stabilizes; if it creeps past 120 in the first 10–15 seconds, I nudge the 1017 at the heater and recheck. @peter_s89 your flush test pairs well with toggling the recirc pump to see if the valve drifts — tankless can cold‑water‑sandwich you otherwise.
Quick example: on homes with recirc, I put a finger on the cold supply at the tub/shower valve after a minute of hot flow; if the “cold” starts creeping warm, the recirc is bleeding through and the mixer’s checks aren’t doing their job, so I call for checks or a swap. @sreynolds made me think of it — first‑draw spiking tends to be worse when that bleed is present. Small caveat: I pass at 118–119 to leave a little buffer for seasonal drift instead of a hard 120.
I dial the mixing stop with a cup under the shower and also log the tub‑spout temp — tiny heads can run hotter at trickle, so I aim 117–118 to stay under ‘120 F’ once it settles. Minor caveat: a leaky diverter spout will skew the mix, so I flag that before judging the valve.
Been adding a quick ‘toilet-flush test’ at the shower while I’m logging 120 F with a calibrated digital thermometer; if a PB body drifts hotter or the cold-shutoff doesn’t choke flow, I flag it. If the ASSE 1016/1070 mark isn’t visible I pop the escutcheon and snap the stamp for the file — @sreynolds is right about tightening checks, but skip IR guns; they lie on water.