I have bought and got installed 3 multi point water heaters. 

The entire 3 only give Luke warm water. 

1 is about 3 metres of pipe 

2 is about the same 

3rd is about half a metre. 

They are Panasonic and 6000kw

Any body have any idea's please 

 

Should be a dial to select wattage, yah?  

What's the model numbers?

DH-6GMA. YES HAVE IT SET TO HI

I can't believe all 3 can be faulty, so we need to look at the installation.

 

Can you check the supply voltage at the heater when it is operating?

 

Do your lights do "interesting" things when the heater starts?

 

Have you verified that any internal RCD/ELCB is reset?

 

2 hours ago, ellathai said:

DH-6GMA. YES HAVE IT SET TO HI

According to the specs and the picture that I can find on the net it has a built in ECLB switch on the lower left corner.  As Crossy said you might try resetting the switches.  I have two  Sharp units that did not work when I installed them.  It turned out to be that the ECLB switch was tripped on both units.  You can not tell from looking at the switch as it is spring loaded as is always flush with the front of the unit, but when pushed they reset and the units have worked fine since.

 

The picture also shows a light on the front, is it on.  My Sharp unit has two lights, one that shows that it has power, the other that shows that the heater is on.  With the ELCB tripped, the power light remains on but the heater light never comes on.

Panasonic DH-6GM4 (DH-6GM4T/W-T) 

220V 3500/6000 watt,

3 L/m (minimum water pressure required: 0.2 Kg / sq.)