One asset, four records

The mechanical subcontract, not the chiller

The chiller appears in the subcontract’s schedule of rates, but the certified cost is a package total that includes installation, pipework and controls. This is ordinary practice and it is the decision that determines everything downstream.

14.2m, of which the chillers are a schedule line

How much was paid, to whom, and when

What this chiller cost, delivered and installed

Not because anyone failed. The question was never asked while the records were open.

11, including compressor, condenser bundle, evaporator, starter, controls

Each is separately located, isolated and maintained. Two of them, the controls and the starter, will be replaced at least once inside the life of the machine.

11 weeks before taking over

This is the date the warranty actually starts on most equipment, and it is why a warranty register built from the handover date is wrong by whatever the commissioning period was.

25.2 years mean life for units replaced; 17.6 years mean age so far for units in service

A distribution, not a number. The replaced units lived from 7 to 42 years, and that spread is the useful part, and it is what gets discarded when a single figure is copied onto a register.

ASHRAE Service Life and Maintenance Cost Database, cooling equipment, chiller, centrifugal: 239 units reported, 209 in service (mean 17.6, median 18.0, standard deviation 8.2, range 3 to 41), 30 replaced (mean 25.2, median 25.0, standard deviation 7.6, range 7 to 42).

What failed, what was done, what is due, and where it is

One asset, with two depreciated components

The machine and the controls, split because their lives differ. The other nine maintainable items are inside the remainder, which IPSAS 45 paragraph 43 requires to be depreciated too.

Cost significant in relation to the total

Significance is measured in money. A cheap component on a critical system is not significant under this test, however important it is to keeping the building open.

IPSAS 45, Property, Plant, and Equipment, paragraph 41: each part of an item with a cost or value significant in relation to the total cost or value of the item shall be depreciated separately. Paragraph 42 permits parts with the same useful life and depreciation method to be grouped.

An apportionment of the package total

Because the project recorded cost by package. The apportionment is a reasonable estimate and it is the basis of a depreciation charge running for two decades.

20 years

A round number, taken from a table. Against the ASHRAE distribution it is defensible; what matters is whether anyone recorded that it was a choice and reviewed it since.

At least at each annual reporting date

IPSAS 45, paragraph 48: the residual value and the useful life of an asset shall be reviewed at least at each annual reporting date, with any change accounted for as a change in an accounting estimate.

25 years, from the manufacturer’s guidance

Five years longer than the life on the fixed asset register, for the same physical machine. Neither number is wrong on its own terms; they answer different questions and nobody has put them side by side.

Failure rate, cost to keep, or no longer meeting the requirement

Whichever arrives first. This is the only one of the four lives that is ever tested against the machine.

Held here, and rarely asked for

The standard points at the operator for evidence that the register is wrong. The annual review at paragraph 48 is usually performed without asking them.

IPSAS 45, paragraph 49: where maintenance policies exacerbate the wear and tear of an asset, its useful life should be reassessed and the asset tested for impairment as appropriate.