Bitzer Compressor
Parts Supplier
4NES · 6FE semi-hermetic reciprocating compressors
What a Bitzer frame code actually names
The Bitzer reciprocating frames named on this page are semi-hermetic, and the frame code stamped on the unit is what tells one from another on a spare-parts request.
4NES · 6FE semi-hermetic frames
The semi-hermetic reciprocating frames met on provision and air-conditioning plants. Valve plates, gasket sets, piston and ring sets and the oil pump items are the usual lines; the refrigerant and the oil charge belong in the request with the type.
Why a semi-hermetic winding fault is not a parts line
On a semi-hermetic machine the motor sits inside the compressor body, so a winding fault is answered as a unit matter rather than as a component one. That is the fork in the request: valve plate, gaskets and rings are parts, a burnt motor is an exchange, and the two are quoted differently.
Reading a Bitzer compressor plate
BITZER was founded by Martin Bitzer in 1934 in Sindelfingen, Germany, where the group is still headquartered. It belongs to no larger group: the parent company, BITZER SE, has a single shareholder, THE SCHAUFLER FOUNDATION, which in BITZER's own words ensures the company's independence and continuity. On board, the frame code and serial number on the unit's own plate — not the plant name — are what identify the specific machine and its spare-parts range. The code stamped on the plate usually runs longer than the bare family name (a typical example is Bitzer 4NES-14), so it is that full string, not just "4NES" or "6FE", that belongs in the request.
A valve plate and a burnt motor are read from the same plate, quoted differently
Every Bitzer reciprocating frame named on this page is semi-hermetic, and that single design choice is what splits every enquiry in two before parts are even named.
Bitzer's 4NES and 6FE reciprocating frames are semi-hermetic: the motor is built inside the compressor housing rather than bolted on as a separate, replaceable unit. That is not a detail buried in the plate reading; it is the fact that decides how a fault is answered. A worn valve plate, a leaking gasket set or a scored piston and ring set are ordinary parts lines, quoted against the frame code and the refrigerant stated in the request.
A burnt or shorted winding is a different conversation. Because the motor lives inside the refrigerant-filled housing, it cannot simply be unbolted from a base frame and sent out the way the separate motor of an open-drive machine can; whether a winding failure is answered by a repair or by an exchange compressor is decided against the frame code, the serial and the electrical data on the plate. A request naming a motor fault is therefore routed as a unit matter from the outset, and stating plainly which of the two a request concerns, a wear part or a winding failure, is what keeps it from bouncing back with a clarifying question.
What a Bitzer reciprocating frame resolves to
Grouped by what a semi-hermetic frame actually opens up to, because the motor stays inside the housing on every one of them.
- Valve plates and reed sets
- Gasket sets for the cylinder head and housing joints
- Piston and ring sets
- Oil pump items
- Terminal-plate and motor-side gaskets, where the housing is opened at that end
- Complete overhaul kits by frame code and serial
- Compressor exchange units, where the motor winding itself has failed
The frame code and the refrigerant are what an inspection needs first on a Bitzer request — naming a wear part or a winding fault plainly is what keeps a mixed list from being answered as one blanket route.
Plate data that makes a Bitzer enquiry quotable
Read the plate on the compressor body itself: a condensing unit or plant often carries a label of its own, and that label need not name the compressor frame. With the items below an enquiry can usually be priced in one pass; without them it comes back with a clarifying question first.
- Frame code — 4NES, 6FE or the equivalent stamped on the plate
- Serial number stamped on the compressor housing
- Refrigerant in service
- Oil charge and oil type
- Whether the fault is a wear part or a suspected winding failure; for a winding failure, add the voltage and frequency printed on the plate
- Photograph of the compressor plate and of the part being requested
Tools for this equipment: the refrigerant number reader for the refrigerant named on the plant and compressor plates. On an air-conditioning plant, the air flow and duct calculator gives the supply air flow for the sensible load of a space and the round or rectangular duct for a chosen velocity.
A gasket set and a burnt motor are not answered alike
Requests naming Bitzer compressor components arrive mixed, and the review differs by what the housing actually separates.
A winding failure on a semi-hermetic frame is not a bolt-on motor change, because the motor sits inside the compressor housing; this line goes to an OEM-route review by default, where a repair or an exchange compressor is weighed against the frame code, the serial and the electrical data on the plate.
Valve plates, gasket sets, piston and ring sets and oil pump items are ordinary wear parts with measurable geometry, and a verified alternative can be reviewed on them where a buyer's approval requirements allow, with dimensional and material documentation checked at RFQ stage. Vessel Core is an independent spare parts supplier and marks the proposed route against each line on the list, so a mixed request naming both a wear part and a motor fault is answered by line, not as one blanket route.
Bitzer compressor parts — questions from the engine room
What does the 4NES or 6FE frame code on a Bitzer compressor actually tell you?
4NES and 6FE are semi-hermetic reciprocating frames met on provision and air-conditioning plants. Valve plates, gasket sets, piston and ring sets and the oil pump items are the usual lines; the refrigerant and the oil charge belong in the request with the type.
Why does a burnt motor cost more than a valve plate on a Bitzer compressor?
On a semi-hermetic machine the motor sits inside the compressor body, so a winding fault is answered as a unit matter rather than as a component one. That is the fork in the request: valve plate, gaskets and rings are parts, a burnt motor is an exchange, and the two are quoted differently.
Is Bitzer part of a larger group?
No. BITZER was founded by Martin Bitzer in 1934 in Sindelfingen, Germany, where the group is still headquartered. The parent company, BITZER SE, has a single shareholder, THE SCHAUFLER FOUNDATION, set up in 2005 by Peter Schaufler and Christiane Schaufler-Münch; BITZER says this ensures the company's independence and continuity.
What should a Bitzer compressor spare-parts RFQ contain?
A workable request lists the frame code (4NES, 6FE or the equivalent stamped on the plate), the serial number, the refrigerant in service and the oil charge, plus whether the fault is a wear part or a suspected winding failure. A photograph of the compressor plate and of the part being requested settles most of the remaining questions in one pass.
Can a Bitzer compressor part be identified without a part number?
Often yes. The decisive evidence is the frame code (4NES, 6FE or the equivalent stamped on the plate), the serial number, the refrigerant in service and a photograph of the removed item beside the nameplate. A part-book page or an earlier order line for the same unit is equally usable as reference.
Is Vessel Core connected to Bitzer?
No, and there is no agreement of any kind. Vessel Core holds no dealership, distribution, representation or partnership agreement with Bitzer, and quoting a component against one of its designations implies no approval by the maker and no claim of interchangeability.
Submit your RFQ now.
Send the frame code and serial from the compressor's own plate, the refrigerant in service and the oil charge, and state whether the request is a wear part or a suspected motor fault. A photograph of the plate and of the part removed covers most of the rest.
