Free Water Heater Commissioning Report for HVAC Contractors

Not for a storage tank, no. Chapter 5 of the IPC contains no maximum storage temperature. 120°F appears as a limit that shower valves (412.3) and bathtub valves (412.5) must be capable of being set to, and 110°F for public lavatories. Tankless heaters do have a real code ceiling of 140°F under 501.6. The 120°F figure everyone quotes for tanks is a CPSC consumer safety recommendation, which is worth following in the right circumstances — but it is not a code citation, and printing it as one on a customer document is how the myth spreads.

The defensible answer is to store at 140°F or above and fit an ASSE 1017 mixing valve to blend down for distribution. That satisfies the Legionella guidance in ASHRAE Guideline 12-2023 and the scald limits at the fixtures at the same time. Storing at 120°F puts the bottom of the tank in the bacterial growth range; storing at 140°F without a mixing valve delivers water that burns an adult in about six seconds. The builder flags both of those, and reports 130°F as the worst of both worlds rather than as a comfortable middle.

No, and this is worth getting right because two different BPI documents publish two different sets of numbers. The action levels this form applies — 0 to 25 proceed, 26 to 100 recommend a fix, 100 to 400 stop work, over 400 an emergency — are from the Building Analyst standard and are measured in undiluted flue gas at steady state, per BPI’s own footnote. A separate document, ANSI/BPI-1200, publishes per-appliance air-free limits where a water heater is 200 ppm. Merging them or relabelling one as the other would be a genuine safety error, so the report states which basis it used.

Whatever the rating plate says. Manifold pressure is model-specific — 4.0 inches water column is typical for natural gas and 10.0 for propane on the units we checked, but those are service-manual figures for particular appliances, not a standard. The often-quoted 3.5 inches is a general gas-appliance rule of thumb and is not a water heater specification at all. The form records what you measured so it can be compared to the plate, rather than judging it against a number we invented.

There is no universal figure, which is why the form asks rather than tells. Manufacturers specify between 450 and 750 cubic feet depending on the unit, with louvered-door and ducted alternatives that change the requirement entirely. Worth knowing too: outside its ambient temperature range a heat pump silently reverts to resistance heating with no user-visible fault, so one installed in an unconditioned garage can run all winter as an ordinary electric heater while the owner believes they bought efficiency.

Not prescriptively. IPC 502.4 requires supports designed for seismic forces in accordance with the International Building Code, and stops there. The familiar two-strap rule — upper third and lower third, with at least 4 inches above the controls — is UPC 507.2. California requires strapping by statute on all new, replacement and existing residential units, with the seller certifying compliance at sale. So the honest phrasing is that the IPC defers to the IBC rather than that it is silent.

Not plain PVC. IPC 504.6 requires the discharge piping to be of a material listed in 605.4, and plain PVC is not on that list — CPVC is. The other discharge requirements catch people too: no threaded connection at the end, no valves or tee fittings, not trapped, gravity flow, and terminating not more than 6 inches above and not less than two pipe diameters above the floor.

No. It is the installer’s record of start-up and handover, and every export says so. Code citations appear to explain why something was checked, not to certify the installation — approval rests with the authority having jurisdiction.