We have not found an official York key to what the leading digits of its part numbers mean, so look up any York part by its full number and check whether it has been superseded. In our own York catalog, though, the first group is a useful hint: 028- numbers are almost all gaskets and seals, including O-rings, 025- numbers are often sensors, fuses, connectors and valves, and 3xx- numbers such as 331-, 366- and 371- are mostly kits.
Is there an official York prefix chart?
Not one we have found. We have not seen a York or Johnson Controls document that defines the leading digits, so the patterns below describe our listings, not a York rule. A pattern is a hint for searching. It is never proof of what a part is or what it fits. The full number, matched against the part, the unit's parts list or the nameplate, is what counts.
York numbers on our site come in a few shapes:
- Three groups with dashes, such as 025-28678-112. This is the usual format for York chiller parts.
- S1- followed by digits, the Source 1 parts brand for York, Coleman and Luxaire. See what S1 means on a York part number.
- AYK580 model strings for the York HVAC drive, such as AYK580-CF-096A-4.
- Other formats, including maker numbers and older short numbers.
What the leading digits look like in our York catalog
We counted our 1,375 active York-brand listings on October 15, 2026. Of those, 27 are complete packaged units or heat pumps, which we left out. The table covers the remaining 1,348 parts, grouped by the first part of the number, with the most common product types our catalog assigns to each group.
| Starts with | Listings | Most common in our catalog | Example listing |
|---|---|---|---|
| S1- | 320 | Motors 73, control boards 36, pressure switches 25, igniters and flame sensors 22 | York S1-6421652 Circuit Board, SSE, 2 Stage, with C | OEM Source 1 Part |
| 025- | 224 | Sensors 47, fuses 30, terminals and connectors 27, valves 26, wire and harnesses 14 | York 025-28678-112 Transducer, Pressure, Evaporator | OEM Chiller Part |
| 028- | 181 | Gaskets and seals 167, fittings and hoses 11 | York 028-14404-000 O-Ring, 3.484" x 0.139" | OEM Chiller Part |
| 026- | 79 | Filters and driers (31 titles name a filter, drier, element, cartridge or core), pumps, fan blades, motors | York 026-37915-000 Element, Filter (10 Micron) | OEM Chiller Part |
| 022- | 54 | Valves 51 | York 022-09539-000 Valve, Transducer | OEM Chiller Part |
| 021- | 53 | Hardware 50, such as cap screws, nuts and washers | York 021-31337-000 Screw, Cap Hex - (1/4 x 3/4) | OEM Chiller Part |
| 024- | 43 | Motors 18, contactors 10, switches 7 | |
| AYK580 | 39 | Variable frequency drives 39 | York AYK580-CF-096A-4 75 HP 380-480V HVAC VFD | Compare to ABB ACH580 |
| 023- | 32 | Fittings and hoses 15, hardware 13 | |
| 029- | 30 | Hardware 14, gaskets and seals 6 | |
| 031- | 20 | Control boards 16 | York 031-01743-002 Control, Board (I/O), YM | OEM Chiller Part |
| 371- | 19 | 14 kits (by title): drive power assemblies (IGBT, diode/SCR), oil pump and gasket kits | York 371-05506-002 Oil Pump Kit | OEM Chiller Part |
| 064- | 19 | Hardware 8, gaskets and seals 5 | |
| 331- | 18 | 16 kits (by title): control and logic boards, microboards, software | York 331-03630-601 Microboard (YK) Kit | OEM Chiller Part |
| 013- | 17 | Chemicals (by title): coolants, inhibitors, caulk, paint and compounds | York 013-03344-000 Coolant Propylene Glycol 5 Gallon | OEM Chiller Part |
| 011- | 17 | Compressor oils (all 17 titles name an oil) | York 011-00533-000 York "K" Compressor Oil, 5 Gallon | OEM Chiller Part |
| 366- | 16 | Maintenance kits 15 (mainly PM kits, by title) | York 366-94952-016 Preventive Maintenance Kit, YK Mod F, G & H (pre-8/2016) | OEM Chiller Part |
| 075- | 16 | Gaskets and seals 12 | |
| 027- | 15 | Filters (including MERV air filters), tube cleaning brushes, compressors (by title) | |
| 325- | 13 | Sensors 9; 11 titles say Kit (temperature, flow and level sensor kits) | |
| 364- | 11 | Filter element kits, seal kits, control shafts (by title; 5 of 11 say Kit) | York 364-50439-000 Filter Element Kit | OEM Chiller Part |
| 092- | 11 | Gaskets and seals 9 | |
| 015- | 9 | Compressors 9 | |
| 36 smaller groups | 70 | 1 to 7 listings each | |
| Other formats | 22 | Maker numbers and short numbers, many of them motors |
Two patterns stand out. Of 103 listings that start with a 3 (322- to 393-), 75 have "Kit" in the title. Of 832 listings that start with 0 (003- to 092-), only 15 do. So in our catalog a 3xx- number usually means a kit or assembly, and a 0xx- number usually means a single component. That is a tendency in our listings, not a York rule, and each group has exceptions.
How to look up a York part number
- Read the full number. Take it from the part's label, the unit's parts list or an old invoice. All three groups matter: 025-28678-112 and 025-28678-115 are different listings.
- Search it in any format. Many of our York listings carry the number with dashes, with spaces and run together as "also searched as" terms, so try 025 28678 112 or 02528678112 as well.
- Check for a replacement number. York replaces and obsoletes numbers over time. A few of our titles say so directly, such as "Replaced by 364-50438-000". See part number supersessions explained.
- Read the title and type. The description should match the part in your hand. If a 3xx- number's title says Kit, check what the kit contains before ordering a single component.
- Confirm against the unit. The prefix tells you nothing about fit. Match the model, style and serial number from the nameplate.
Parts involved
| Component | Role in this issue | Where to find it |
|---|---|---|
| All York chiller parts | Search or browse the chiller range by number | York Chiller Parts |
| O-rings and seals | Most 028- numbers in our catalog | York Chiller O-Rings & Seals |
| Sensors and transducers | The largest product type among 025- numbers | York Chiller Sensors, Thermistors & Transducers |
| Kits | Most 3xx- numbers in our catalog | York Chiller Maintenance & Repair Kits |
| Source 1 parts | S1- numbers | York Source 1 (S1) Replacement Parts |
| All York parts | Every York-brand listing, plus some listings from other brands | York Replacement Parts |
Scope: The counts come from our own catalog: 1,375 active York-brand listings on October 15, 2026, grouped by the leading part of the number in each title and by the product type our catalog assigns. They describe our listings, not York's full parts range. We have not found a York prefix key. Product types are our catalog's labels. The products above are examples, not a fit confirmation.
Before you order
Confirm the unit's model, style and serial number from the nameplate, and read the full number off the old part. For nameplate help, see how to find the correct part from the model and serial number. To confirm a number or find a replacement, contact us at help@totalhvacparts.com or 302-219-4994 with the part number, model and serial number.
Frequently Asked Questions
What does 025- mean on a York part number?
We have not found a York prefix key. In our York catalog, 025- numbers are often sensors, fuses, terminals and connectors, and valves. Use the full number and check supersession; the prefix alone does not identify the part.
Are York 364- and 371- numbers kits?
Often for 371- in our catalog (14 of 19 titles say Kit), and sometimes for 364- (5 of 11 titles say Kit). Across all 103 listings whose number starts with a 3, 75 have Kit in the title. 371- kits include drive power assembly and oil pump kits; 364- kits include filter element and seal kits. Some 3xx- numbers are single parts.
What do York 028- part numbers cover?
In our York catalog, 167 of 181 listings starting with 028- are typed as gaskets and seals, a group that includes O-rings. Check the size in the title against the part you are replacing.
How do I find a York part if the number has been replaced?
Search the old number first; some listings name the replacement in the title. If nothing comes up, send us the number with the model and serial number and we will check it against York's replacement information.
Sources
- Total HVAC Parts catalog: 1,375 active York-brand product listings (titles and product types), counted October 15, 2026
- No York or Johnson Controls document defining part number prefixes was found; the patterns above describe our listings only
- Live product titles for the parts listed above, as shown on each product page
Chiller, furnace and drive parts involve line voltage, refrigerant under pressure, fuel gas on heating equipment and rotating equipment. Service should be performed only by qualified personnel, following the manufacturer's documentation for your unit and your facility's lockout/tagout procedures.