What should a hot-water recirculation quote spell out?

For a fair comparison, I’d want each quote to state the pump’s control mode and schedule, the proposed return path, and where and how the hot-water piping will be insulated. It should also say how commissioning will verify that hot water arrives when expected and how the controls will be set. Ask for estimated operating hours or energy use, with the assumed daily hot-water-use pattern and energy prices shown separately; then the convenience and running-cost assumptions are visible rather than buried in a generic payback estimate.

I’d weigh the inconvenience, not just count the waits: frequent delays that interrupt cooking or a morning routine could make the upfront cost worthwhile, while occasional waits are harder to justify against installation and ongoing energy costs. If use is concentrated at predictable times, I’d also be more interested in whether the proposed controls can target those periods rather than keeping the system active all day.

I’d also ask how each return-path option affects ordinary cold-water use, not only the pump’s energy estimate. With a cold-water-pipe return, does the proposal account for the possibility that water at a cold tap may initially be warmer than expected? That comfort trade-off could matter even if the operating-cost comparison looks favorable.

Yes, that’s a reasonable comfort issue to clarify before comparing prices. I’d ask the installer to describe what someone should expect at a cold tap with the proposed cold-pipe return, and how the controls and layout limit unintended warming. If avoiding that effect is important, it could outweigh a lower installation quote; I wouldn’t assume the energy estimate captures the inconvenience.

For example, if a hypothetical household repeatedly runs into a long wait during a narrow morning rush, a schedule aimed at that window might address the most disruptive delay without making all-day circulation the default. If waits are scattered and rarely interrupt anything, that same schedule may offer less value; I’d compare the expected convenience with its actual operating pattern rather than assume faster water is equally useful all day.

It may help to separate the pump’s electricity from heat lost as hot water circulates through the pipes. Insulation can reduce that heat loss, while longer circulation hours can increase it; a quote should state what it assumes about both, rather than treating pump power as the whole running cost. That makes the comparison between schedules more meaningful.

Two quotes could show the same pump electricity yet imply different running costs if one assumes short, scheduled circulation and the other longer operation. The difference could widen if the piping insulation assumptions also differ. I’d compare the estimated heat loss and circulation hours alongside pump power, rather than treating equal pump wattage as equal total operating cost.