Still running a controller from 1986? Let's find its modern match.

Your old controller has put in more hours than a boombox at a block party. When it's time for a replacement, whether it's obsolete, hard to find or just tired, send us the part number. We'll cross it to a current Watlow or Eurotherm model that fits your panel and your process. Totally tubular, zero guesswork.

How it works (easier than a puzzle cube)

  1. Send the part number or a photo of the controller's label (the side label usually has the full model code).
  2. We match it. Same DIN size and panel cutout where possible, plus matched sensor inputs, control and alarm outputs, supply voltage and communications.
  3. We show you what's different. We'll call out any wiring, terminal or menu changes before you order. Ask us about pre-configuration.
  4. Local support. Need help with setup or a quick walkthrough on the new menus? We're in Burnsville, MN, and we answer the phone. No busy signal, no rewinding.

Any brand, obsolete or not

Like a good mixtape, we'll mix and match. We work from the manufacturers' own migration guides whenever they exist. When one doesn't, we cross by specs: DIN size, inputs, outputs, alarms and comms. We carry Watlow and Eurotherm, along with Tempco, Gefran, Carlo Gavazzi, Pyromation, Tutco and Nelson for the rest of the heat loop.

Common crossovers we see (the greatest hits)

  • Watlow Series SD, 93, 96, 97, 935, 965 → Watlow EZ-ZONE PM / PM PLUS
  • Watlow Series 981/982, 988/989 → Watlow EZ-ZONE PM (1/8 DIN)
  • Watlow Series F4 → Watlow F4T
  • Eurotherm 2216e / 2208e / 2204e and 2416 / 2408 / 2404 → Eurotherm EPC3016 / EPC3008 / EPC3004
  • Not on the list? Send it anyway. B-sides welcome. That's what we're here for.

Send us your part number

Tell us what you've got. We'll get back to you with a match within one business day.

Below the form: Prefer to talk? Call 1-877-ENTHERM (1-877-368-4376) or email sales@entherm.com. Ask us about pre-configuration.

Small print: Crossovers are recommendations based on manufacturer retrofit guides and the information you provide. Replacements may differ in fit, wiring or features, and we'll point out any differences. Always confirm that safety and limit devices are in place when retrofitting.

FAQ

  • Will it fit my existing panel cutout? Usually, yes. We match the DIN size first. Watlow's guides map 1/32, 1/16, 1/8 and 1/4 DIN legacy models to the same DIN size in EZ-ZONE PM, and Eurotherm's EPC3000 comes in the same 1/16, 1/8 and 1/4 DIN sizes as the 2200/2400 series.
  • Will the wiring be the same? Not always. Watlow's guides note wiring and programming differences on some crossovers, and we'll tell you exactly what changes.
  • Can you match my communications? Tell us what you use today. EPC3000 offers Modbus RTU/TCP, EtherNet/IP, BACnet and EIA-485, and Watlow's PM family has several comms options. We'll match yours or suggest the closest fit.
  • Can you set it up before it ships? Ask us about pre-configuration.

Your old controller had a great run, like a high score nobody could beat. Let's get you to the next level. Find my match

Sourced crossover quick reference

Legend: ✅ = stated in the manufacturer's own document · ⚠️ = inferred or uncertain, confirm before publishing

Legacy model Status Manufacturer's recommended replacement Confidence / notes Source
Watlow Series SD (1/32, 1/16, 1/8V, 1/8H, 1/4 DIN) Retired; Watlow retrofit guide published EZ-ZONE PM, same DIN size (PM3/PM6/PM8/PM9/PM4). Example: SD3C-HCAA-AAAA → PM3C1CA-AAAAAAC ✅ Guide says replacements "will differ in fit and form," with notes on relay and comms differences [W1]
Watlow Series 93 (1/16 DIN) Retired PM PLUS (e.g., 93AA-1CA0-00GG → PM6C1CA-BAAAPWP) or PM LEGACY Express (PM6C1CA-BAAAHWP) ✅ Guide notes "wiring & programming differences" [W2]
Watlow Series 96 (1/16 DIN) Retired EZ-ZONE PM, 1/16 DIN (e.g., 96A0-CAAA-00GG → PM6C1CA-AAAADAA) ✅ Note: "Check output location" [W3]
Watlow Series 97 (1/16 DIN, control + limit) Retired EZ-ZONE PM integrated limit, 1/16 DIN (e.g., 97A0-DAAA-00GG → PM6L1AJ-AAAAAAA) ✅ Notes on relay differences and limit on output 2 [W4]
Watlow Series 935 (1/32 DIN) Retired EZ-ZONE PM 1/32 DIN (e.g., 935A-1CC0-000G → PM3T1CC-AAAAAAA) ✅ Note: "No remote" [W5]
Watlow Series 965 (1/16 DIN) Retired EZ-ZONE PM Express or PM Standard, 1/16 DIN ✅ Guide lists both. ⚠️ PM Express itself is now discontinued, and Watlow points to PM PLUS [W6][W10]
Watlow Series 981/982 (1/8H DIN) Retired EZ-ZONE PM 1/8H DIN (PM9…) ✅ (981 guide checked; 982 assumed similar ⚠️) [W7]
Watlow Series 988 (1/8V DIN) Retired EZ-ZONE PM 1/8V DIN (e.g., 988A-10BA-AAGG → PM8C2AK-…) ✅ Note: 3-cycle time base, check suppressor on inductive loads [W8]
Watlow Series 989 (1/8H DIN) Retired EZ-ZONE PM 1/8H DIN (e.g., 989A-10BA-AAGG → PM9C2AK-…) ✅ [W9]
Watlow Series F4 (F4S/F4D) ramping controller Retired F4T base plus flex modules (e.g., F4SH-CAA0-01AA → F4T1A2EAA1A1AAA + modules) ✅ Notes on wiring, programming and comms differences, and no event board support [W11]
Watlow EZ-ZONE PM (all DIN sizes) Watlow: "PM PLUS is intended to replace the EZ-ZONE PM… expect obsolescence" PM PLUS (same pinouts and settings per Watlow FAQ). Jan 2026 guides map PM4 (1/4 DIN) to PM PLUS ✅ So the full path for old 9xx/SD units is legacy → EZ-ZONE PM part → PM PLUS equivalent. ⚠️ Confirm PM PLUS availability for each DIN size [W10][W12]
Watlow EZ-ZONE PM Express Discontinued (Watlow product page) PM PLUS ✅ [W13]
Eurotherm 2204e / 2208e / 2216e Discontinued (Eurotherm obsolescence list) EPC3000 range: EPC3004 (1/4), EPC3008 (1/8), EPC3016 (1/16) ✅ Eurotherm: "EPC3000 … is the recommended upgrade or replacement for Eurotherm 2200 and 2400" in the same DIN sizes. ⚠️ Mapping by DIN size is ours. Confirm I/O per order code [E1][E2][E3]
Eurotherm 2404 / 2408 / 2416 Discontinued (some variants still available: 2404F/2408F Profibus, 2408i) EPC3004 / EPC3008 / EPC3016 ✅ Eurotherm 2400 page: "suggested replacement, the EPC3000." ⚠️ Profibus and DeviceNet variants: check comms (EPC3000 lists BACnet, EIA-485, EtherNet/IP, Modbus RTU/TCP, with no Profibus listed) [E1][E2][E4]
Eurotherm 2116 / 2132 (2100 series) 2116: End of Service; 2132: Discontinued Not specified. Eurotherm says "contact technical support" ⚠️ A 3200 (3216) or EPC3016 is a plausible match by specs, but that's unverified. EPC2000 is DIN-rail/surface mount, so it isn't a panel drop-in [E1][E5]
Eurotherm 808 / 815 / 818 series End of Service Not specified. Eurotherm says "contact technical support" ⚠️ Crossed case by case on specs only [E1]
Eurotherm 3216L Discontinued Not specified ⚠️ The standard 3216 is still listed as current in the 3200 range [E1][E6]

Sources

  • [W1] Watlow Series SD Retrofit Guide (incl. embedded "Series SD Source.pdf"): https://www.watlow.com/-/media/documents/retrofit-guides/series-sd-retrofit-guide-03042015.ashx
  • [W2] Watlow Series 93 Retrofit Guide (PM PLUS / PM LEGACY): https://www.watlow.com/-/media/documents/retrofit-guides/series-93-retrofit-guide-08182021.ashx
  • [W3] Watlow Series 96 Retrofit Guide: https://www.watlow.com/-/media/documents/retrofit-guides/series-96-retrofit-guide-070714.ashx
  • [W4] Watlow Series 97 Retrofit Guide: https://www.watlow.com/-/media/documents/retrofit-guides/series-97-retrofit-guide-03272012.ashx
  • [W5] Watlow Series 935 Retrofit Guide: https://www.watlow.com/-/media/documents/retrofit-guides/series-935-retrofit-guide-10162014.ashx
  • [W6] Watlow Series 965 Retrofit Guide: https://www.watlow.com/-/media/documents/retrofit-guides/series-965-retrofit-guide-04152013.ashx
  • [W7] Watlow Series 981 Retrofit Guide: https://www.watlow.com/-/media/documents/retrofit-guides/series-981-retrofit-guide-090311.ashx
  • [W8] Watlow Series 988A Retrofit Guide: https://www.watlow.com/-/media/documents/retrofit-guides/series-988a-retrofit-guide-090111.ashx
  • [W9] Watlow Series 989A Retrofit Guide: https://www.watlow.com/-/media/documents/retrofit-guides/series-989a-retrofit-guide-090111.ashx
  • [W10] Watlow PM PLUS FAQ: https://www.watlow.com/-/media/documents/specification-sheets/pm-plus-faq-1119.ashx
  • [W11] Watlow Series F4 to F4T Retrofit Guide: https://www.watlow.com/-/media/documents/retrofit-guides/series-f4-to-f4t-retrofit-guide.ashx
  • [W12] Watlow EZ-ZONE PM4C → PM PLUS Retrofit Guide (Jan 2026): https://www.watlow.com/-/media/documents/retrofit-guides/pm4c-retrofit-01072026-1.ashx
  • [W13] Watlow "DISCONTINUED: EZ-ZONE PM Express": https://www.watlow.com/products/controllers/Integrated-Multi-Function-Controllers/EZ-ZONE-PM-Express
  • Watlow Retrofit Guides index (75 guides, incl. 800-series, 92/94/942/945, PD, V4, MicroDIN): https://www.watlow.com/resources-and-support/technical-library/retrofit-guides
  • [E1] Eurotherm Discontinued and Obsolete Products list: https://www.eurotherm.com/en/support/discontinued-and-obsolete-eurotherm-products/
  • [E2] Eurotherm EPC3000 page ("recommended upgrade or replacement for Eurotherm 2200 and 2400"): https://www.eurotherm.com/products/temperature-controllers/single-loop-temperature-controllers/epc3000-programmable-controllers/
  • [E3] Eurotherm (IT) "Sostituzione dei Regolatori Serie 2200e e 2400" (same 1/4, 1/8, 1/16 DIN sizes): https://www.eurotherm.com/it/temperature-control-it/sostituzione-dei-regolatori-serie-2200e-e-2400/
  • [E4] Eurotherm 2400 page ("Most variants … no longer available … suggested replacement, the EPC3000"): https://www.eurotherm.com/us/products/temperature-controllers-us/single-loop-temperature-controllers-us/2400-temperature-controller-programmer/
  • [E5] Eurotherm EPC2000 page (DIN rail and surface mounting): https://www.eurotherm.com/en/products/temperature-controllers-en/single-loop-temperature-controllers-en/epc2000-programmable-controllers/
  • [E6] Eurotherm 3200 page: https://www.eurotherm.com/en/products/temperature-controllers-en/single-loop-temperature-controllers-en/3200-temperature-process-controller/