Replacement heaters for industrial equipment are one of the most common procurement tasks in plant maintenance. The heater has failed, the equipment is down (or heading that way), and you need a replacement that fits and works. The speed and accuracy of the quotation you receive depends almost entirely on the quality of the information you provide in your request.
This checklist helps you prepare an RFQ (request for quotation) that gives the supplier everything they need to quote correctly the first time, without multiple rounds of clarification.
Why This Matters
A vague RFQ (“need a cartridge heater, please quote”) forces the supplier to ask a series of follow-up questions: what diameter, what length, what wattage, what voltage, what leads? Each round of questions and answers adds hours or days to the quotation process. In a breakdown situation, that delay is costly.
A complete RFQ gives the supplier the information to identify the right product, check availability or manufacturing requirements, calculate the price and respond with a quotation. One round, one response.
The Checklist
Step 1: Identify the Heater Type
What kind of heater are you replacing?
- [ ] Cartridge heater (cylindrical, fits in a bore)
- [ ] Band heater (wraps around a barrel or cylinder)
- [ ] Immersion heater (sits in a liquid)
- [ ] Coil heater (wound heater, typically for hot runners)
- [ ] Strip heater (flat, bolt-on)
- [ ] Infrared heater (radiant, not contact)
- [ ] Tubular heater (bent tube element)
- [ ] Other (describe)
If you are not sure what type of heater it is, a photo of the failed heater (or the location where it sits in the equipment) is worth more than a guess.
Step 2: Gather Dimensions
Measure the heater itself, or measure the space it fits into:
- [ ] Diameter (for cartridge heaters: both the heater OD and the bore ID)
- [ ] Length (active heating length, overall length)
- [ ] Width (for band heaters, strip heaters)
- [ ] Shape (straight, U-bend, L-shape, coiled)
- [ ] Any cutouts, slots or special features
Use a caliper or micrometer for precise measurements. “About 12 mm” is less useful than “12.05 mm measured with digital caliper.”
Step 3: Record Electrical Specifications
- [ ] Wattage (usually stamped on the heater or on the equipment nameplate)
- [ ] Voltage (check the heater label, the equipment wiring diagram, or the supply circuit)
- [ ] Single-phase or three-phase (for higher-wattage heaters)
If the original heater label is unreadable, check the equipment manual or the machine manufacturer’s parts list.
Step 4: Identify Materials
- [ ] Sheath material (stainless steel, Incoloy, copper, etc.)
- [ ] If it is an immersion heater: what liquid does it sit in?
- [ ] If it is a band heater: mica or ceramic type?
If you cannot identify the material, describe the appearance and the application.
Step 5: Note the Lead and Termination
- [ ] Lead type (fibreglass wire, stainless steel braid, flexible conduit)
- [ ] Lead length (measure from the heater body to the connection point)
- [ ] Connector type (bare leads, terminal box, plug connector, pin terminals)
- [ ] Lead exit position (for band heaters: where does the lead exit relative to the clamping hardware?)
Step 6: Additional Details
- [ ] Internal thermocouple (type, position)
- [ ] Mounting hardware included (clamps, bolts, brackets)
- [ ] Equipment make, model and heater zone (helps the supplier cross-reference)
- [ ] Part number from the original heater (if readable)
- [ ] Quantity needed
- [ ] Urgency (standard lead time or urgent)
Step 7: Attach Supporting Materials
- [ ] Photos of the old heater (show the label, the leads, the overall shape)
- [ ] Photos of the heater location in the equipment
- [ ] Equipment manual pages showing heater specifications
- [ ] Drawing or sketch if available
- [ ] Previous purchase order or quotation reference
A Template You Can Copy
Subject: Replacement heater enquiry
Heater type: [e.g., Cartridge heater] Diameter: [mm] Bore diameter: [mm, if applicable] Length: [mm] Wattage: [W] Voltage: [V] Sheath material: [e.g., SS 304] Lead type: [e.g., fibreglass leads] Lead length: [mm] Thermocouple: [None / Type K at tip] Equipment: [make, model, zone] Quantity: [number] Urgency: [Standard / Urgent]
[Attach photos and drawings]
What Happens After You Submit
A good supplier reviews your RFQ, confirms the specifications internally, and responds with a quotation that includes the product description, unit price, quantity pricing (if applicable), estimated delivery and any terms. If anything is unclear, they ask before quoting, not after.
If you receive a quotation that does not match your RFQ specifications, compare carefully. The supplier may have identified an issue (such as an incompatible watt density for the bore fit) and recommended an alternative. Ask for an explanation of any differences.
Related Reading
-
- Comparing Custom Heater Quotations: what to check once quotations arrive
- FAQ: How do I request a quotation?
- Products overview