View Full Version : Mitsi Problems

26-05-2004, 08:40 PM
Hi All,
Got a problem with a misubishi/daiya Unit
Model FDCP508HES3 R407 3 phase.

Problems: Outdoor unit not cutting in, fitted gauges only 20 psi each side poss low on gas, do they have LP Switches ?

To test my theroy i put in 150psi of OFN & disconnected the wires from the compressor and switched on to see if the contactor pulled in (It Didn't).
Quick look at the diagram it looks like the A1 of the contactor comes off a relay which switches fom the crank heater to the A1 does this mean the A1 which comes off output 52c on the board only comes on once the crank heater has warmed the pot up. If so how does it tell when its wam enough.
I couldn't find a leak to left the unit under pressure overnight to see how much it drops.

There are wo LED's on the board, one red & one green. Nothing going on the the red but the green one just keeps flashing, as far as i am aware this means the system should be OK.

Just had another thought, The label on the unit say's Mitsubishi/daiya Heavy industries. Does this mean its from a seperate part of the mitsi empire than the one that makes the M Series. Sould have also said the fault codes i was getting was U57 E01, I am assuming this is a general outdoor fault code but cannot see this on any Mitsi list i have got.

Any help would be appreciated.



26-05-2004, 11:40 PM
Raymond, first item... the crankcase heater is energised when the compressor is OFF
second item, I will try and check the Mitsi tech disks for further info.

27-05-2004, 11:03 AM
Mitsubishi Electric and Mitsubishi Heavy Industries are complete different products.
We have better experiences with Electric.

28-05-2004, 09:12 PM
Hi Raymond any joy with the mitsi

Ref the leak I,ve had quite a few problems with R407c as the molecules are smaller than that of ofn.

R407c is R134a 52%
R32 23%
R125 25%

I have not enjoyed working with it and I belief they are phasing it out and replacing it with

R410a R32 50%
R125 50%
This I enjoy working with and have had no problems
So far

The glide is similar with the latter

Regards bernard

29-05-2004, 04:28 PM
Hi Guys,
Havn't been back yet, too busy running around doing stupid jobs for a certain customer. Plan is to go back, check ofn pressure, vac out and regas to see what's happening when in running mode.
Normally just deal with mitsi-elec and don't have too many probs this is he first time i have run into Misi-heavy and so far not impresed



06-06-2004, 06:47 PM

I've had problems in the past with the Heavy Industries kit-if it was Mitsubishi Electric I could be more certain. The best thing might be to speak to the technical support guy at 3D Air who distribute the Heavy Industries (I believe the controls etc are all different from the Electric ones). Let me know if you want his contact details.


06-06-2004, 07:00 PM
Hi Iceman,
All OK, Found v/small leak on main suction flare. vac'd out & regassed and working fine. I must admit, i also prefer Electric to Heavy Industries.



06-06-2004, 07:30 PM
Glad you found the problem. I also had a leak problem with one of their VRF systems at the start of Spring.

06-06-2004, 07:58 PM
hi raymond,

this little gadget is the ultimate connection.
can be open and closed 100's of times and will never leak.

cost less then all the work involved in repairing a leak.

does wonders for your reputation. :)


picture can be seen here http://www.refrigeration-engineer.com/forums/showthread.php?t=1636

12-02-2005, 07:22 PM
for mitsi heavy indust advice get in touch with the uk distributor it is called 3d air i dont have the number ,look in your contractors handbook
they are normally v helpful