Ariston
Ariston Thermostat (Regulation) 999578
Ariston regulation thermostat, part 999578, for Microsystem 10 RFFI and 15 RFFI gas boilers.
At a glance
- Appliance family: Microsystem 10 RFFI and Microsystem 15 RFFI
- Also known as 1577716
£21.86
£18.22 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 999578 is a regulation thermostat used in Ariston Microsystem 10 RFFI and 15 RFFI gas boilers. It monitors and regulates the boiler's operating temperature so that heating and hot water output track the demand set at the controls. It is a serviceable control component within the boiler's temperature regulation circuit.
Signs this part needs replacing
- The boiler fails to hold the temperature set at the controls, running consistently hot or cold.
- Radiators or hot water reach temperature and then fall away before the set point is met.
- The boiler short-cycles, firing and shutting down more frequently than normal.
- Heating or hot water temperature drifts noticeably between cycles.
- Temperature regulation faults appear alongside erratic burner behaviour.
Before you order
- Confirm the appliance model is an Ariston Microsystem 10 RFFI or 15 RFFI.
- Check the boiler serial number against the ranges listed in the Fits section.
- For edition models, confirm the edition and date shown on the appliance data badge.
- Isolate the boiler from the electrical supply before fitting any control component.
Compliance
| Barcode / EAN | 5411692341992 |
|---|---|
| Alternative numbers | 1577716 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ARISTON ARISTON MICROSYSTEM 10 RFFI - FROM SERIAL No 2320021100001 TO SERIAL No 2320024900001 | — | — | — | |
| ARISTON ARISTON MICROSYSTEM 10 RFFI - FROM SERIAL No 2320101600001 TO SERIAL No 2320106400001 | — | — | — | |
| ARISTON ARISTON MICROSYSTEM 15 RFFI - FROM SERIAL No 2320021100001 TO SERIAL No 2320024900001 | — | — | — | |
| ARISTON ARISTON MICROSYSTEM 15 RFFI - FROM SERIAL No 2320101600001 TO SERIAL No 2320106400001 | — | — | — | |
| ARISTON MICROSYSTEM 10 RFFI LPG EDITION 1 (AUG 2000) | 41-116-04 | 41-116-04 | — | — |
| ARISTON MICROSYSTEM 10 RFFI LPG EDITION 2 (FEB 2001) | 41-116-04 | 41-116-04 | — | — |
| ARISTON MICROSYSTEM 10 RFFI LPG EDITION 3 (FEB 2004) | 41-116-04 | 41-116-04 | — | — |
| ARISTON MICROSYSTEM 10 RFFI LPG EDITION 4 (SEPT 2004) | 41-116-04 | 41-116-04 | — | — |
| ARISTON MICROSYSTEM 10 RFFI NG EDITION 1 (AUG 2000) | 41-116-04 | 41-116-04 | — | — |
| ARISTON MICROSYSTEM 10 RFFI NG EDITION 2 (FEB 2001) | 41-116-04 | 41-116-04 | — | — |
Showing 10 of 20 compatible appliances.
Documents & drawings
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
ARISTON appliance manual — MICROSYSTEM 10 RFFI LPG EDITION 1 (AUG 2000) (GC 41-116-04), MICROSYSTEM 10 RFFI LPG EDITION 2 (FEB 2001) (GC 41-116-04), MICROSYSTEM 10 RFFI LPG EDITION 3 (FEB 2004) (GC 41-116-04), MICROSYSTEM 10 RFFI LPG EDITION 4 (SEPT 2004) (GC 41-116-04), MICROSYSTEM 10 RFFI NG EDITION 1 (AUG 2000) (GC 41-116-04), MICROSYSTEM 10 RFFI NG EDITION 2 (FEB 2001) (GC 41-116-04), MICROSYSTEM 10 RFFI NG EDITION 3 (FEB 2004) (GC 41-116-04), MICROSYSTEM 10 RFFI NG EDITION 4 (SEPT 2004) (GC 41-116-04)
manualmanualARISTON appliance manual — MICROSYSTEM 15 RFFI LPG EDITION 1 (AUG 2000) (GC 41-116-05), MICROSYSTEM 15 RFFI LPG EDITION 2 (FEB 2001) (GC 41-116-05), MICROSYSTEM 15 RFFI LPG EDITION 3 (FEB 2004) (GC 41-116-05), MICROSYSTEM 15 RFFI LPG EDITION 4 (SEPT 2004) (GC 41-116-05), MICROSYSTEM 15 RFFI NG EDITION 1 (AUG 2000) (GC 41-116-05), MICROSYSTEM 15 RFFI NG EDITION 2 (FEB 2001) (GC 41-116-05), MICROSYSTEM 15 RFFI NG EDITION 3 (FEB 2004) (GC 41-116-05), MICROSYSTEM 15 RFFI NG EDITION 4 (SEPT 2004) (GC 41-116-05)
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