The short answer
On a DCS dishwasher, why the water or the dry cycle is not hot comes down to a short list, and on this line the order is not the generic one. The diagnosis starts at the seal on whichever layout you actually have — drawer lid or hinged door, because the older badge covers both layouts, so the first job is establishing which one is in front of you: the seal that fails is a different part, in a different place, in each case. The first three checks below need no tools and no parts; the point at which this stops being an owner job is stated further down, as a condition rather than as a recommendation.
What you are seeing
- The load comes out wet at the end of a cycle that includes a dry phase.
- The tub is barely warm at the end of a wash.
- Greasy soil is left on plastics and on the upper rack.
- The heated-dry option makes no difference when selected.
- The cycle runs much longer than usual as the machine waits for temperature.
- A burnt smell or a discoloured spot on the element.
- Note: Near-miss symptoms that mean a different fault: If the load is dry but dirty, that is the cleaning page. If plastics are wet but the rest of the load is dry, that is normal — plastic holds no heat. If the machine never fills, the heat complaint is downstream of a fill fault.
Causes, ranked for a DCS dishwasher
- The seal on whichever layout you actually have — drawer lid or hinged door — Why this rank: The older badge covers both layouts, so the first job is establishing which one is in front of you: the seal that fails is a different part, in a different place, in each case.
- A blocked vent or a machine unloaded too late — Why this rank: A machine left closed after the cycle recondenses onto the load, which reads as a drying failure.
- A high-limit thermostat or thermistor out of range — Why this rank: A protective thermostat that has opened will not close again, and the machine will heat nothing while reporting nothing.
- Incoming water not hot enough — Why this rank: The machine boosts the temperature it is given; if the supply arrives cold the machine spends the whole cycle catching up.
- No rinse aid, so water clings instead of sheeting off — Why this rank: Most drying is water sheeting off hot dishes, not evaporation, and without rinse aid the load stays wet whatever the element does.
- A control not calling for heat — Why this rank: It is last because a heat circuit fails at the element or the thermostat far more often than at the command.
What to check, in order
- Run the hot tap at the sink until it is hot, then start the cycle and feel the tub partway through. — Order: First — Why: It separates the household water temperature from the machine in one cycle and at no cost.
- Check that a heated-dry or high-temperature option is actually selected for the cycle you use. — Order: Second — Why: It is free, it is invisible on the panel of many machines, and it explains the complaint completely on eco cycles.
- Check the rinse-aid reservoir and fill it. — Order: Third — Why: Drying is mostly a sheeting effect, so this is the cheapest real improvement available.
- With the power off, look at the element for breaks, blisters or discolouration. — Order: Fourth — Why: A visibly damaged element ends the diagnosis, and an intact one moves it to the thermostat.
Steps a homeowner can take
- Switch the machine off at its breaker before touching the element or removing a panel. — Tools: none — Time: a moment
- Run the hot tap at the sink until the water runs hot, then start the cycle immediately. — Tools: none — Time: several minutes
- Select a cycle with the heated-dry and high-temperature options switched on, and note the difference. — Tools: owner manual — Time: an hour or more
- Fill the rinse-aid reservoir and set it to a mid position. — Tools: rinse aid — Time: several minutes
- With the machine cold and off, inspect the element along its whole length for breaks, blisters and discolouration. — Tools: flashlight — Time: several minutes
- Open the door as soon as the cycle ends and let the load steam off before unloading. — Tools: none — Time: several minutes
Before you start
Safety
Switch the machine off at its breaker before touching the element or removing a panel. A capacitor can hold a charge after the power is off. The element stays hot long after a cycle ends and will burn on contact. Never rest plastic on the tub floor where it can touch the element, and never test an element with the machine energised.
When this stops being an owner job
Call when the supply water is hot, the correct options are selected, rinse aid is present and the element looks intact, and the load is still cold and wet. Confirming an element or a high-limit thermostat is a resistance measurement on a disconnected circuit.
Sources
General guidance- The control of hazardous energy (lockout/tagout), and manufacturer service-manual practice — OSHA 1910.147 / manufacturer service manuals, fetched 2026-09-06
Nearest pages
Generalized information
This page is generalized: it covers DCS across a whole dishwasher range rather than one family or one model, and where a more specific page exists it is linked here. It does not cover the current DCS by Fisher & Paykel badge and model-level pages, and it does not carry serial-range or model-group detail — check the rating plate before ordering any part. DCS by Fisher & Paykel Dishwasher: Not Heating — Slug: dcs-by-fisher-paykel-dishwasher-heating-failure — Covers: the DCS by Fisher & Paykel line specifically
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
