Ariston
Ariston Thermostat (Regulation) 921048
Regulation thermostat (IMIT) for Ariston Comfort STI cylinders, part number 921048.
£45.42
£37.85 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Ariston 921048 is a regulation thermostat manufactured by IMIT for Ariston Comfort STI cylinders. It monitors and regulates stored water temperature, switching the heat source to hold the cylinder at its set point. It is a service part for the Comfort STI range, including the indirect and Protech variants.
Signs this part needs replacing
- Stored water temperature drifts above or below the set point
- Cylinder overheats or fails to reach temperature
- Heat source runs continuously without the thermostat cutting out
- Temperature readings become erratic or inconsistent between draws
- Hot water runs cool despite the cylinder thermostat being turned up
Before you order
- Confirm your appliance model against the fitment list above
- Check the appliance serial number falls within the stated range where one is given
- Compare the part number on the existing thermostat with 921048
- Isolate the power and water supplies before removing the old thermostat
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ARISTON ARISTON COMFORT INDIRECT STI 125 - FROM SERIAL No 98000000089052 TO SERIAL No 000000000890215 | — | — | — | |
| ARISTON ARISTON COMFORT INDIRECT STI 125 PROTECH - FROM SERIAL No 000000000890215 | — | — | — | |
| ARISTON ARISTON COMFORT INDIRECT STI 150 - FROM SERIAL No 980000000890503 TO SERIAL No 000000000890216 | — | — | — | |
| ARISTON ARISTON COMFORT INDIRECT STI 150 PROTECH - FROM SERIAL No 000000000890216 | — | — | — | |
| ARISTON ARISTON COMFORT INDIRECT STI 210 - FROM SERIAL No 980000000890504 TO SERIAL No 000000000890217 | — | — | — | |
| ARISTON ARISTON COMFORT INDIRECT STI 210 PROTECH - FROM SERIAL No 000000000890217 | — | — | — | |
| ARISTON COMFORT STI 125 PROTECH EDITION 1 (NOV 2000) | — | — | — | |
| ARISTON COMFORT STI 150 PROTECH EDITION 1 (NOV 2000) | — | — | — | |
| ARISTON COMFORT STI 200 PROTECH EDITION 1 (NOV 2000) | — | — | — | |
| ARISTON Comfort Indirect Protech STI 125 Litre | — | — | — |
Showing 10 of 17 compatible appliances.
Documents & drawings
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