hot liquid and suction lines

[djs]

probably an easy answer but i cant see why both the liquid and suction lines are hot.
this is on a 9kw highwall split unit, air off 47 air on 20
500psi on heat
but not really performing well ,as in it doest kick up to high fan, and no its not oversized.

any ideas

[ktm]

U sure your compressor is pumping?

[djs]

yes hence 500psi

[djs]

also sounds like is boiling in the indoor unit

[monkey spanners]

Filters and coil clean? Fan blade/blower wheel clean?

Where are you taking your temperature measurements? Just wondering as the interconecting pipe work will be hot during heating mode. I expect the liquid line is in fact an expansion line.

[chemi-cool]

500 psi sounds like you use air as refrigerant.

Evacuate and recharge.

Check that 4 way valve performs OK.

[monkey spanners]

500 psi sounds like you use air as refrigerant.

Evacuate and recharge.

Check that 4 way valve performs OK.

Like Chemi says thats a high pressure, what refrigerant is it using? I hope the system is on R410A with pressures like that!

[nike123]

probably an easy answer but i cant see why both the liquid and suction lines are hot.
this is on a 9kw highwall split unit, air off 47 air on 20
500psi on heat
but not really performing well ,as in it doest kick up to high fan, and no its not oversized.

any ideas

What is unit make and model? What is outdoor temperature?

On high wall split system in heating mode both lines are part of condenser and therefore both should be hot.
One hotter than another (one little below of compressor discharge temperature and other little below condenser saturation temperature).

Recover and weigh charge. It is best to evaluate performance by observing temperature difference and air flow before recovery and evacuation.

Δt of 27°C at indoor heat exchanger is sligtly high and could point to problem with insufficient air flow. Maybe fan speed is not on high, or filter and heat exchanger is dirty, or fan condenser is faulty, etc...

If you have lines longer than unit is charged for, you need to calculate additional amount of refrigerant and see if it is added or not.
Than charge correct amount and see if unit is performing OK by measuring air flow and air in and out temperature difference.

[nike123]

500 psi sounds like you use air as refrigerant.

Evacuate and recharge.

Check that 4 way valve performs OK.
Chemi, it could be R410a.
500 PSI is 34.5 Bar which is 57°C CST which looks to me perfectly OK.

[chemi-cool]

You can be on the right side, lets wait and see.

Meanwhile you can enjoy the Chinese drivers....:rolleyes:

http://www.youtube.com/watch_popup?v=QESfEd180rQ

[nike123]

Meanwhile you can enjoy the Chinese drivers....:rolleyes:



At least they are driving pretty slow.:D

[djs]

thanks for all replys ,it is on 410A so i expect around 500psi, the pipe is only 3mtrs so the supplied charge should be ok.
imthinking i might move the themostat from the unit to the opposite wall.
the unit is a mitsubishi ge80