Split air conditioning help

Skyfire · 30 Jul 2006 at 05:53

Hi,

I bought a 12,000 BTU split air con. unit for a small bedroom with no windows or heat sources, it has two pipes, in the manual, it says connect the pipes, evacuate the air by letting a little gas out (done!). Now the air is evacuated, as instructed, the valves are fully open, I have checked for leaks. and everything checks out. However, although it is a little cool, it is not very cool and where the indoor unit pipes are, the pipes have huge blocks of ice around them even with insulation, what do you think could be the matter? My supplier reckons I've let all the gas out of the outdoor unit and says I will need to get someone out to recharge it, but I think this is carp coz there is defo no leaks, and it is cooling, but not much?

Mickey_D · 30 Jul 2006 at 07:38

Was there anything about removing shipping stuff?

If BOTH lines running from the indoor unit to the outdoor are forming ice block I would have to say that there is no heat transferring happening in the indoor unit.

Pop the cover(s) off the indoor unit and check for any styrofoam blocks/forms inside that are restricting the airflow in there.

Failing that, check to make sure the damper is open......

RJC · 30 Jul 2006 at 09:42

Were the pipes quick coupler connections or did you need to screw the pipe work on using a spanner.

Also check that the valves are fully open by the condenser unit.

If the unit was short gas the liquid line would only be frosty / cold, as by the time it reaches the indoor unit all the liquid would have evaporated and he suction line would be warm (larger pipe).

As both lines are cold like Mickey_D said there is no heat transfer.

Whats the discharge air like coming out of the condenser unit outside, is this warm, also check to see if the condenser fan is running.

Is this a heatpump unit, if so try it in heating mode for a short while, assuming your is cool enough

.

Rob

EDIT: Is it possible to post some pictures.

fatty1 · 30 Jul 2006 at 11:04

Looks like you are short on gas I have heard these units are ok unless you have one that may have leaked some gas ??

Skyfire · 30 Jul 2006 at 12:43

RJC said:
Were the pipes quick coupler connections or did you need to screw the pipe work on using a spanner.

Also check that the valves are fully open by the condenser unit.

If the unit was short gas the liquid line would only be frosty / cold, as by the time it reaches the indoor unit all the liquid would have evaporated and he suction line would be warm (larger pipe).

As both lines are cold like Mickey_D said there is no heat transfer.

Whats the discharge air like coming out of the condenser unit outside, is this warm, also check to see if the condenser fan is running.

Is this a heatpump unit, if so try it in heating mode for a short while, assuming your is cool enough .

Rob

EDIT: Is it possible to post some pictures.

Thanks for the great suggestions, unfortunately I do not have a camera but it is a Toyo a/c. I have checked for pipe kinks and for packaging and everything is fine, the vents are not blocked. I do not know what the damper is so cannot check if it is open or closed? Both lines have ice blocks but only because the small refrigerant line ice block is bridging the other larger pipe when it grows. The larger pipe is slightly warm to the touch in cooling mode. The pipes were screwed on tight using a spanner?

The refrigerant line is very cool in cool mode, so cool in fact, my fingers stick to it like glue. The outdoor unit is expelling mildly warm air, all the fans are running at full whack. I tried in heating mode for a short while as suggested and the larger line was very very warm, the air coming out of the indoor unit was just mildly warm. I tested the low gas theory by expelling a little air but only refrigerant came out at high pressure so I think there is lots of gas?

RJC · 30 Jul 2006 at 14:40

Skyfire said:
Thanks for the great suggestions, unfortunately I do not have a camera but it is a Toyo a/c. I have checked for pipe kinks and for packaging and everything is fine, the vents are not blocked. I do not know what the damper is so cannot check if it is open or closed? Both lines have ice blocks but only because the small refrigerant line ice block is bridging the other larger pipe when it grows. The larger pipe is slightly warm to the touch in cooling mode. The pipes were screwed on tight using a spanner? The refrigerant line is very cool in cool mode, so cool in fact, my fingers stick to it like glue. The outdoor unit is expelling mildly warm air, all the fans are running at full whack. I tried in heating mode for a short while as suggested and the larger line was very very warm, the air coming out of the indoor unit was just mildly warm. I tested the low gas theory by expelling a little air but only refrigerant came out at high pressure so I think there is lots of gas?

Hi,

I think the problem is low charge, basicaly the refrigerant is boiling off in the line (thats why your fingers are sticking to the line), by the time it reached the indoor unit only a small amount of liquid is left, ie 95% vapor 5% liquid.

Out of curisoty how long did you purge the lines for.

Rob

Skyfire · 30 Jul 2006 at 21:20

RJC said:
Hi,

I think the problem is low charge, basicaly the refrigerant is boiling off in the line (thats why your fingers are sticking to the line), by the time it reached the indoor unit only a small amount of liquid is left, ie 95% vapor 5% liquid.

Out of curisoty how long did you purge the lines for.

Rob

Ahh I see, this sounds plausible. I opened the refrigerant for 6-7 seconds then purged the air with all the valves closed. This was then repeated, the pipes are 2 metres long so say 15 seconds total

RJC · 30 Jul 2006 at 21:45

Skyfire said:
Ahh I see, this sounds plausible. I opened the refrigerant for 6-7 seconds then purged the air with all the valves closed. This was then repeated, the pipes are 2 metres long so say 15 seconds total

Unfortunately due to the small amount of refrigerant smaller splits hold that 15 seconds can lose most of the charge, a call to a local fridge engineer to recharge is in order im afraid.

Rob

Mickey_D · 30 Jul 2006 at 23:35

Totally OT, but RJC what is that in your sig?!?!?

RJC · 30 Jul 2006 at 23:58

Mickey_D said:
Totally OT, but RJC what is that in your sig?!?!?

Screw compressor out of a air cooled chiller.

Mickey_D · 31 Jul 2006 at 00:04

Very odd. Never seen anything like that before......

Skyfire · 31 Jul 2006 at 02:28

RJC said:
Unfortunately due to the small amount of refrigerant smaller splits hold that 15 seconds can lose most of the charge, a call to a local fridge engineer to recharge is in order im afraid.

Rob

Ta m8