Potterton
Potterton PCB Modulation Control 21/18601
Modulation printed circuit board for Potterton Combi 80/100 and PUMA 80/100 E boilers.
At a glance
- Also known as 1120856
£258.00
£215.00 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 Potterton 21/18601 is a printed circuit board that provides modulation control on Potterton Combi and PUMA gas boilers. It governs the modulating gas valve signal so the burner output tracks demand rather than running at a fixed rate. The board is used across the Combi 80 and Combi 100 appliances and the PUMA 80 E and PUMA 100 E models fitted with SIT or Honeywell controls.
Signs this part needs replacing
- Boiler runs at a fixed firing rate with no modulation response to demand
- Repeated lockouts or flame failure after the burner has lit
- Erratic or intermittent heating and hot water output
- Burner fails to respond when the boiler reaches or drops below setpoint
- Visible damage, scorching or corrosion on the board itself
Before you order
- Confirm the appliance model and, where known, the GC number against the manufacturer's parts list
- Check whether the boiler is fitted with SIT or Honeywell controls, as this board covers those variants
- Compare the part number printed on the existing board with 21/18601 before ordering
- Isolate the electrical supply and follow the manufacturer's instructions when fitting
Compliance
| GC number | 289-551 |
|---|---|
| Barcode / EAN | 5039177582885 |
| Alternative numbers | 1120856 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| POTTERTON COMBI 100 | 47-393-04 | 47-393-04 | — | — |
| POTTERTON COMBI 80 | 47-393-03 | 47-393-03 | — | — |
| POTTERTON POTTERTON COMBI 80 | — | — | — | |
| POTTERTON POTTERTON PUMA 100 E SIT / HONEYWELL CONTROLS | — | — | — | |
| POTTERTON POTTERTON PUMA 80 E SIT / HONEYWELL CONTROLS | — | — | — | |
| POTTERTON PUMA 100 E SIT / HONEYWELL CONTROLS | 47-590-13 | 47-590-13 | — | — |
| POTTERTON PUMA 80 E SIT / HONEYWELL CONTROLS | 47-590-11 | 47-590-11 | — | — |
Documents & drawings
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