The short answer
Cool dishes from a BlueStar dishwasher usually mean the water arriving is cold rather than that the element has failed. In a large kitchen the machine sits a long way from the water heater, so the first fill is whatever was standing in the pipe. Run the tap hot before you start the machine, and see whether the complaint survives.
What you are seeing
- The tub and dishes are cool at the end of a full programme
- No steam escapes when the door is opened at the end
- Dishes are clean but completely wet, particularly plastics
- The cycle runs longer than usual and finishes cold
- The machine stops and reports a fault after the heat step
- A near-miss symptom: white film on hot dishes, which is a hardness problem rather than a heat one
- Body: Distinguish a cold machine from a machine that only dries badly: The tub and dishes are cool at the end of a full programme. No steam escapes when the door is opened at the end. Dishes are clean but completely wet, particularly plastics. The cycle runs longer than usual and finishes cold. The machine stops and reports a fault after the heat step. A near-miss symptom: white film on hot dishes, which is a hardness problem rather than a heat one.
Causes, most likely first
- A cold first fill from a long pipe run — Why: the machine takes whatever is standing in the pipe, and in a large kitchen that is a lot of cold water, which the cycle then has to recover from.
- A low-temperature or eco programme selected — Why: the machine is doing exactly what was asked, and the resulting cool load is not a fault at all.
- Rinse aid empty, presenting as poor drying — Why: drying depends on water sheeting off the load, so an empty reservoir gives wet dishes that owners report as a heat failure.
- Scale insulating the heating element — Why: without an internal softener, hard water deposits build on the element and it can no longer transfer heat, which is why results decline gradually.
- A failed thermistor — Why: the board stops calling for heat because the sensor claims the water is already hot, giving a full-length cycle that stays cold throughout.
- A failed heating element — Why: genuine and not rare on hard water, and the sign is a cycle that halts with a fault rather than one that simply runs cool.
- Body: Ranked for a machine on a long hot-water run without its own softener: First, A cold first fill from a long pipe run: the machine takes whatever is standing in the pipe, and in a large kitchen that is a lot of cold water, which the cycle then has to recover from. Second, A low-temperature or eco programme selected: the machine is doing exactly what was asked, and the resulting cool load is not a fault at all. Third, Rinse aid empty, presenting as poor drying: drying depends on water sheeting off the load, so an empty reservoir gives wet dishes that owners report as a heat failure. Fourth, Scale insulating the heating element: without an internal softener, hard water deposits build on the element and it can no longer transfer heat, which is why results decline gradually. Fifth, A failed thermistor: the board stops calling for heat because the sensor claims the water is already hot, giving a full-length cycle that stays cold throughout. Sixth, A failed heating element: genuine and not rare on hard water, and the sign is a cycle that halts with a fault rather than one that simply runs cool.
What to check, in order
- run the kitchen tap until it is genuinely hot, then start the machine immediately and compare.
- check which programme is selected, because an eco cycle explains a cool load with nothing wrong.
- fill the rinse-aid reservoir, since wet dishes are far more often a rinse-aid problem than a heat problem.
- if a hot fill on a full programme still ends cold, the fault is scale, the sensor or the element, and the machine has to be opened.
- Body: Remove the water-supply variable first: First, run the kitchen tap until it is genuinely hot, then start the machine immediately and compare. Second, check which programme is selected, because an eco cycle explains a cool load with nothing wrong. Third, fill the rinse-aid reservoir, since wet dishes are far more often a rinse-aid problem than a heat problem. Fourth, if a hot fill on a full programme still ends cold, the fault is scale, the sensor or the element, and the machine has to be opened.
Checks you can do yourself
- Run the kitchen tap hot, then start the longest programme immediately with the tub empty — Tools: none — Time estimate: an hour or more
- Open the door at the end and feel the tub walls for warmth and look for steam — Tools: none — Time estimate: a few minutes
- Fill the rinse-aid reservoir and raise the dose one step, then run a normal load — Tools: rinse aid — Time estimate: a few minutes
- Switch off at the breaker and look at the element in the sump for white scale or discolouration — Tools: torch — Time estimate: a few minutes
- Run a proprietary descaler on the hottest empty programme and compare the next normal load — Tools: descaler — Time estimate: an hour or more
- Body: Three comparisons will identify which of the remaining causes you have: Run the kitchen tap hot, then start the longest programme immediately with the tub empty (none; an hour or more). Open the door at the end and feel the tub walls for warmth and look for steam (none; a few minutes). Fill the rinse-aid reservoir and raise the dose one step, then run a normal load (rinse aid; a few minutes). Switch off at the breaker and look at the element in the sump for white scale or discolouration (torch; a few minutes). Run a proprietary descaler on the hottest empty programme and compare the next normal load (descaler; an hour or more).
Safety first
Safety
Unplug the appliance or switch off its breaker before removing any panel. A capacitor can hold a charge after the power is off. This machine is hardwired, so the breaker is the only isolation. Never test the element with power connected, never mix a descaler with a bleach product, and let the machine cool before reaching into the sump. unplug-before-service
When to stop and call a technician
Past the supply and consumables, this is a service call: A long programme with a hot fill still finishes cold. The cycle stops and reports a fault after the heat step. The element is visibly scaled and a descaling cycle does not restore results. The breaker trips as the heat step begins. A long programme with a hot fill still finishes cold The cycle stops and reports a fault after the heat step The element is visibly scaled and a descaling cycle does not restore results The breaker trips as the heat step begins
Nearest pages of the same kind
What this page does not cover
This page is generalized across every dishwasher sold under the BlueStar name: it separates neither the panel-ready cabinets from the stainless-fronted ones and one control generation from another, and it names no individual model. Where a family- or model-specific page exists it is linked here and it outranks this one for that machine; at present no page beneath this one narrows to a single family, so treat the ranking above as the brand-level pattern rather than a reading of your serial plate. For the other faults that turn up on this machine, start from Common BlueStar Dishwasher Problems.
Related pages
- Common BlueStar Dishwasher Problems
- BlueStar Dishwasher: Abnormal Noise or Vibration
- BlueStar Dishwasher: Does Not Clean or Dry
- BlueStar Dishwasher: Controls, Display or Error Code
- BlueStar Dishwasher: Cycle Will Not Run or Complete
- BlueStar Dishwasher: Door, Latch or Seal Fault
- BlueStar Dishwasher: Will Not Drain
- BlueStar Dishwasher: Electrical, Fire or Gas Hazard
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
