Tornado RFI Filter 31067

The Tornado RFI Filter 31067 is the genuine OEM radio-frequency interference filter fitted in the power input of the PS Series professional spotters. It is an electrical component, not an air filter: a line filter wired between the incoming mains supply and the machine’s switch and motor. It also fits the Tornado PS8226 Spotter 98226, the 230-volt build of the deluxe PS Series spotter.

Compatible Models for the RFI Filter

• Tornado PS Spotter 98220 — PS Series professional spotter, 115V
• Tornado PS8221 Spotter 98221 — the 230-volt build of the same spotter
• Tornado PS8225 Spotter 98225 — deluxe PS Series spotter
• Tornado PS8226 Spotter 98226 — the 230-volt build of the deluxe PS Series spotter, Series D & E

Tornado’s factory cross-reference returns this filter on the 98220 from Series E onward, on Series F and G of the 98221, on the 98225, and on the Tornado CFV 125 critical filter vacuum — eight machines in all, and the list is complete rather than truncated. We publish only the models we can confirm against Tornado’s current catalog; call us at 763-535-0770 with your model and serial number if yours is not listed.

What an RFI filter is for

A universal motor with carbon brushes generates electrical noise. Every time a brush crosses a commutator segment it makes and breaks a circuit, and that produces a broadband burst of radio-frequency energy. With nothing to stop it, that noise travels back out along the power cord and into the building’s wiring, where it becomes interference that other equipment on the same circuit has to live with.

The filter is a passive network — inductors and capacitors in a shielded can — that gives the high-frequency noise an easy path to neutral and earth while passing the 50/60 Hz supply untouched. It works in both directions, so it also protects the machine’s own switch and electronics from spikes arriving from the supply.

It is worth being clear why this part exists on a cleaning machine: it is there so the equipment meets the electromagnetic-compatibility requirements it was certified against. A machine running without its line filter is outside that certification, even though it will appear to work perfectly. On the 98220 it is grouped in the parts book with the power cord, the strain relief and the rocker switch — the whole mains input assembly.

When to replace it

A line filter usually fails in one of two ways. It can fail open, which makes the machine dead: no power past the filter, and nothing downstream of it works even though the cord and plug test good. Or its internal capacitors can fail short or leaky, which typically shows up as a tripped breaker or a residual-current device that trips the moment the machine is plugged in, sometimes before the switch is even touched.

Replace it if the can is cracked, swollen, scorched or has leaked; if the terminals are corroded, loose or burnt; if the wiring at the filter shows heat damage; or if there is any sign of arcing around it. Replace it rather than attempt a repair — this is a sealed, safety-relevant part at mains potential.

If a machine trips an earth-leakage device on plug-in with the switch off, the line filter is one of the first things to suspect, because its capacitors are connected across the supply at all times.

Fitting notes

Isolate the machine from the mains before the electrical cover comes off and keep it isolated throughout. Photograph or label the wiring before disconnecting anything: a line filter has a defined line side and load side, and fitting one the wrong way round defeats its purpose.

Connect the earth. The filter’s noise path runs to earth, and an unearthed filter neither works nor is safe. Make every terminal up cleanly and check nothing is left loose. Fit a new electrical cover gasket while you are in there so the enclosure seals again — on a wet machine that gasket is what keeps moisture away from everything you have just worked on. Make sure no wiring is pinched as the cover closes, and test the machine on an earth-leakage protected supply before returning it to service.

Twin City Vacuum has been selling and servicing Tornado equipment since 1956.

You can browse every assembly for this machine on our Tornado PS Spotter 98220 parts page, and the manufacturer’s specifications are published at tornadovac.com.

Frequently Asked Questions

What does the RFI Filter 31067 actually do?

It is a mains line filter, not an air filter. A brushed motor produces broadband radio-frequency noise every time a brush crosses a commutator segment, and the filter gives that noise an easy path to neutral and earth while passing the 50/60 Hz supply untouched. It also shields the machine’s switch from spikes arriving from the supply.

My machine trips the breaker as soon as I plug it in. Could it be the RFI Filter?

It is one of the first things to check. The filter’s capacitors sit across the supply whenever the machine is plugged in, so a leaky or shorted one can trip an earth-leakage device before the switch is even touched. The other failure mode is the opposite — it fails open and the machine is simply dead with a cord and plug that test good.

Can I just bypass the RFI Filter to get the machine running?

No. It is fitted so the machine meets the electromagnetic-compatibility requirements it was certified against, and its capacitors are also connected to earth for safety. A bypassed machine will appear to work normally while being outside its certification. Replace the filter rather than remove it, and never attempt to repair a sealed component at mains potential.

How do I order the RFI Filter (part# 31067) or get help?

Call us at 763-535-0770 to order the RFI Filter (part# 31067) — this is a factory-order part and we will confirm current pricing and the right version for your serial number when you call. Our staff at 5415 West Broadway, Crystal, MN 55428 has been servicing Tornado equipment since 1956.

Questions? Call us at 763-535-0770 or visit us at 5415 West Broadway, Crystal, MN 55428.