Liftmaster Maxum Parts
LiftMaster Maxum Parts — JDC, RJDC, JHDC and TDC
Genuine LiftMaster replacement parts and accessories for the Maxum industrial DC door operators. Pick your operator type below, or jump straight to the accessories.
Read your model number off the operator label before ordering. Motors, frames, sprockets, chains and transformers all vary by door weight, duty cycle and supply voltage — the frame letters alone are not enough.
Which Maxum Do I Have?
All four frames run the same 24V DC control platform, so the main board, EMI boards, control box and toroidal transformers are shared. What separates them is how the operator mounts and how you disconnect it from the door.
| Frame | Type | Disconnect | Door weights | Drive output |
|---|---|---|---|---|
| JDC | Jackshaft, no hoist | None — battery backup is included so the door still runs in a power cut | 700 lb | 65:1 gearbox, #50 chain |
| RJDC | Jackshaft with manual release | Pull the sash chain to disconnect. Built left-hand or right-hand and not field-changeable | 700 lb | 65:1 gearbox, #50 chain |
| JHDC | Jackshaft with hoist | Green engage and red disengage ropes, then move the door by hand chain | 700 / 1200 / 2200 lb | 65:1 gearbox, #50 chain |
| TDC | Trolley | Quick-disconnect door arm | 700 / 1200 / 2200 lb | 65:1 gearbox, #48 chain on 700, #41 on 1200 and 2200 |
Jackshaft and Hoist Parts — JDC, RJDC, JHDC
JDC, RJDC, JHDC Maxum Jackshaft & Hoist Parts — motors, gear box and encoder assemblies, main and EMI boards, control box, toroidal transformers, operator frames, hoist chains and ropes, manual release parts.
- JDC7S1BMC
- JDC7S4BMC
- JDC7S1BE
- JDC7S4BE
- RJDC7S1BEL
- RJDC7S4BEL
- RJDC7S1BER
- RJDC7S4BER
- JHDC7S1BMC
- JHDC7S4BMC
- JHDC7S1BE
- JHDC7S4BE
- JHDC12S1BMC
- JHDC12S4BMC
- JHDC12X1BMC
- JHDC12X4BMC
- JHDC12S1BE
- JHDC12S4BE
- JHDC12X1BE
- JHDC12X4BE
- JHDC22X1BMC
- JHDC22X4BMC
Trolley Parts — TDC
TDC Maxum Trolley Operator Parts — trolley, front idler, header bracket, door arm kits, drive sprockets, #41 and #48 door drive chain kits, motors, boards and transformers.
Accessories and Field-Installable Kits
Maxum DC Operator Accessories & Kits — photo eyes, monitored edges, light curtains, wall controls, remotes and receivers, battery backup, heaters, covers, transformer kits, chain guards and sprocket kits.
- CPS-U photo eyes
- LMTBUL thru-beam
- OES optical edges
- DCWALLCTL wall control
- DC7AH battery backup
- COVERDC operator cover
- HTR120NC heater kit
- XF208 / XF600 transformer kits
- Chain guards and tensioners
- Sprocket kits
- Traffic lights and loop detection
- Interlock switches
Maxum Specifications
| Duty cycle | S models 20 cycles per hour. X models 30 cycles per hour on firmware 1.17 and earlier, 100 cycles per hour on firmware 1.21 and later. |
|---|---|
| Battery backup | Included on the JDC, capable but not included on RJDC, JHDC and TDC. About 20 cycles from a full charge within 48 hours of losing AC power. |
| Voltage | 120/240V single and three phase, or 480V three phase, as dedicated model numbers. 208V and 600V sites are handled with a step-down transformer kit. |
| Braking | Dynamic braking on 700, 1200 and 2200. The 2200 adds an electromechanical holding brake. |
| Door speed | About 12 in./sec on sectional doors, 8–9 in./sec on rolling steel. Fine adjustment is in the wall controller menu; larger changes are made by swapping the drive sprocket. |
| Limits | Electronic, set at floor level through the LCD wall controller. |
| Temperature | −4°F to 149°F as standard, or −40°F to 149°F with a heater kit. Indoor use only. |
| In the carton | Every Maxum ships with a CPS-U photo eye and the DCWALLCTL LCD wall controller. |
Reading a Maxum Model Number
The frame letters come first: J = jackshaft, RJ = jackshaft with manual release, JH = jackshaft with hoist, T = trolley. Then DC, then the door weight (7 = 700 lb, 12 = 1200 lb, 22 = 2200 lb), the duty cycle (S = standard, X = extended or continuous), and the voltage (1 = 120/240V single or three phase, 4 = 480V three phase). B means battery-backup capable, E is the 3 inch extended shaft, and MC carries no significance. On the RJDC only, a trailing L or R is the handing.
So a JHDC12X4BE is a hoist jackshaft for a 1200 lb door, continuous duty, 480V three phase, battery-backup capable, with the 3 inch shaft.
Maxum Part Number Formats
| Format | What it is | Example |
|---|---|---|
| K41-0xxx-000 | Maxum service kits — motors, boards, frames, transformers, encoders | K41-0388-000MC main board |
| TDC48-xx / TDC41-xx | Trolley door drive chain kits. The number after the dash is the maximum door height in feet; 48 and 41 are the chain pitch | TDC41-16 fits doors to 16 ft |
| 71-15xxBxxLGH | Operator sprocket kits, by chain size, tooth count and bore | 71-1550B10LGH, 10-tooth, #50, 1 in. bore |
| XF208VACx / XF600VACx | Step-down transformer kits. The trailing 7 or 12 is the operator size | XF208VAC12 for 1200 and 2200 |
| 1910929FTxx | JHDC hoist chain, cut to length in feet | 1910929FT25, 25 ft |
Common Maxum Repairs
| Symptom | Where to look |
|---|---|
| Door stops short, overtravels, or limits drift | Encoder, or the full motor / gear box / encoder assembly — jackshaft and hoist or trolley |
| Nothing happens, no display on the wall controller | Toroidal transformer sized to your door weight and voltage, or the bridge rectifier |
| Operator dead after a storm or line surge | EMI board — there is a separate 480VAC board and 120/240VAC board |
| Motor weak, sparking, or running hot on an X model | Motor brush kit |
| Chain slack, chain jumping the sprocket | Take-up bolt, drive sprocket for your pitch, and a chain kit cut to your door height |
| Door binds or judders along the rail | Trolley, front idler and tracker spacer |
| Hoist chain slips, or the ropes will not disengage | Hoist assembly and engage / disengage ropes |
| Manual release will not re-engage | RJDC manual release subassembly |
| 2200 lb door drifts down when stopped | Brake service kit — 2200 models only |
| Remotes and accessories stopped pairing | Antenna, or the main board |
Frequently Asked
Will parts from my old L5 operator fit a Maxum?
No. The Maxum is a 24V DC platform and shares no drive or control parts with the L5 generation. The one exception is mounting: the HOISTMOUNTMODDC bracket kit lets a JDC, RJDC or JHDC go onto an existing L5 GH mounting pattern.
How do I slow the door down?
Small changes are made in the wall controller menu. For a real reduction, go down a sprocket size. A 12-tooth to 10-tooth swap on a jackshaft or hoist drops speed about 20%, and on a TDC12 the 16-tooth #41 sprocket does the same job.
My building is 208V or 600V. Can I still use a Maxum?
Yes. Maxums are built as 120/240V or 480V units, and a step-down transformer kit handles 208V and 600V sites. Order the kit that matches your operator size.
What comes in the box with a new Maxum?
A CPS-U monitored photo eye and the DCWALLCTL LCD wall controller are included with every unit. Sprockets, track and trolley chain are ordered separately.
Can a Maxum go outside?
No. These operators are rated for indoor use only. With a heater kit fitted they will run down to −40°F, but they still need to be under cover.
Also Available
Complete Maxum DC operators · LiftMaster commercial door operator parts
The LiftMaster Maxum range replaced the earlier L5 commercial line with 24V DC operators offering standard, extended and continuous duty cycles, built-in battery backup capability and myQ Facility compatibility. All four frames share the same control platform, while the drive train, frames and disconnect hardware are specific to each. GateHouse Supplies stocks genuine LiftMaster service parts for every Maxum configuration — JDC and RJDC jackshaft, JHDC hoist and TDC trolley, in 700, 1200 and 2200 lb sizes, on 120/240V single and three phase and 480V three phase. If you are unsure which part fits, have the full model number and serial number from the operator label ready and call us at (866) 965-5599.