Malibu Intermatic Inc. ML121RT Low Voltage 121-Watt Power Pack with Timer - Answered Questions & Fixed issues


Mine is a ML121rt. Lights just went dead one day. Took it apart and found a spider egg in the switch and the contacts slightly fouled. The switch comes apart easily. Cleaned it and hit the contacts with a point file. Good as new. Tools needed: Torx bit, voltmeter, point file.

Malibu... | Answered on Jul 26, 2019 | 170 views


I've done a lot of reading and research on Malibu

No replacement parts for Power pack, or schematic >> Malibulights.com shows replacement lights and replacement power packs
Manual for Malibu 600 Watt power pack

SAVE the pins off old power pack and see if they match pins on new power pack ... because you can't find pins on the internet

When the power pack goes bad or you lose the pins, then you buy another power pack

Things to remember:
Match number of lights to power pack wattage
30 - 20 Watt bulbs => 30 x 20 = 600 Watt power pack
Replace bulbs as soon as they burn out, or other bulbs will burn out quickly, and I think it causes power pack to burn out sooner too.

Up-vote if this helped. Thanks for the feedback.

Malibu... | Answered on Nov 28, 2015 | 485 views


There are two possible problems you could be facing (excluding the transformer going bad) If you have replaced light bulbs with higher wattage ones, you could be drawing too much current through the transformer. (It is common for MR-16 style lightbulbs to be 20w in landscape lights, but 50w for inside lights, and the local hardware store usually only carries the 50w replacement lamps) Each transformer has a specific amount of "watts" it can supply (anywhere from 100w to 1000w) If you exceed the supply wattage of the transformer, the breaker inside the transformer will trip. The quick and easy way to test this is to take a few of the lightbulbs out and see if the breaker will hold.
If you are positive that the total lamp wattage does not exceed the rating of the transformer the second possible problem (but less likely) is that you have a lamp socket or wire connection that is full of water. This water between the two conductors draws current just like a light bulb and can cause an overcurrent fault. This is usually more common if it starts to trip right after a heavy rain when the ground gets saturated with water.

Good Luck!

Malibu... | Answered on Apr 18, 2015 | 1,970 views


Malibu... | Answered on Oct 17, 2014 | 413 views


Timer module not sold separately

http://waterheatertimer.org/Malibu-power-pack-stopped-working.html#troubleshoot

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Malibu... | Answered on Oct 17, 2014 | 537 views


http://waterheatertimer.org/Malibu-power-pack-stopped-working.html#troubleshoot
Plug into cheap wall timer
Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Malibu... | Answered on May 18, 2019 | 678 views


Try it... should work
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html#install
However minimum load for ML121 is 80% load rating.. so 80 watts is ok for 100 watt transformer... 60 watts is low and can cause early failure of transformer.
Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Malibu... | Answered on Oct 17, 2014 | 231 views


Plug into cheap wall timer
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html#troubleshoot

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Malibu... | Answered on Oct 17, 2014 | 1,951 views


Hot transformer is fire hazard... warmish transformer is normal... replace transformer
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Malibu... | Answered on Oct 17, 2014 | 184 views


Malibu... | Answered on Oct 17, 2014 | 32 views


Malibu... | Answered on Oct 17, 2014 | 76 views


Malibu... | Answered on Oct 17, 2014 | 32 views

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