The ice looks wrong
Why are my ice cubes hollow?
Hollow cubes mean the mould is not filling all the way, so the shell freezes before the middle arrives. The fill is short, not the freeze. Denver Sub-Zero Repair Experts starts at the inlet valve screen, then the house pressure behind it, then the valve itself — and a new filter on its own rarely changes anything, because a filter does not meter the fill.
Pattern
What we usually find
- Scale across the inlet valve screen. It builds for months, shortens each fill by a little, and shows up as hollow cubes long before it shows up as an empty bin.
- House pressure that sags. Sub-Zero quotes a working range of either 20 to 100 psi or 35 to 120 psi depending on the model, and a supply that only just clears it will not clear it when something else draws water.
- The valve itself. A solenoid that has passed hard water for years stops opening fully, and once it is marginal, cleaning the screen buys weeks rather than years.
- A line throttled at the shut-off: a valve left part-closed after a remodel, or a compression fitting nipped up on a kinked tail.
Most often first. Order comes from what the visits keep turning up, not from a count.
What the cube shape is telling you
A cube hollow in the middle froze from the outside in and ran out of water before the centre arrived. That is a volume problem, and volume is decided upstream of the mould — which is why the mould is the last thing looked at rather than the first.
Undersized but solid cubes are the same fault one step earlier. Cloudy cubes are a different fault altogether, and belong to the freeze rather than to the fill.
Before you call
Two minutes, before anyone comes out
- Find the shut-off for the ice maker line and confirm it is fully open, not part-way.
- Change the filter if nobody can remember when it was last done.
- Empty the bin, note the time, and see what has arrived three hours later.
Stop there. If that has not settled it by the next morning, call Denver Sub-Zero Repair Experts on (720) 903-2603 and the rest of the water path gets traced with a meter.
When it needs somebody out: Ice Maker Repair in Denver.