Question about Whirlwind FH-778 Air Conditioner

1 Answer

5 ton split LG UNIT brand new about 1 year old.

The lowside pressure is listed 90-100psi. i clean the condenser and the evaporator coil and filter. check the oms reading on the compressor which is ok. i notice the compressor is so hot. i grab me 2 bags of ice to cool down the compressor. then i start the unit and pressure went down to 70 then i goes back to 90-100 range. my partner told me it might be the compressor is not pumping well or it overheated. Can you help me out?

Posted by on


1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Master
  • 2,359 Answers

Look up the term BLACK DEATH.

90-100 psi is very high on the low side.

Without spending too much time,I would pull a vacuum to -28 inch of mercury and let it sit over night.

Monitor the manifold garage for leak. (rise of inch of mercury)

My bet is the low quality LG compressor's worn out metal part is in the condenser.

Blockage will increase the low side PSI.

You can buy HVAC blow out can/chemical to clean line before you vac and fill the refrigerant.

Please let me know what's you founding is on reply.

Posted on Jul 11, 2010


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Carrier split heat pump leaking condensate at right side of air handler and left side of outside condenser. Have had recharged once since new, unit is 1 plus years old

it sounds like coil may need leveled or drain cleaned out and if needed more refrigerant system has a leak and needs to be found and repaired. Is everything new (tubing,evaporator,and heat pump)?if so leak should be at a welded joint may be under insulation

Oct 29, 2013 | Heating & Cooling

2 Answers

Hi,Ice on the suction and discharge line in LG split a/c. Please help me to clear this issue. Thanks.

Check and clean condenser coils with good coil cleaner
Put exterior fan on it to veify it.

If this was helpful please rate me.
Leo Ponder Appliance-Tyler,Texas

Aug 22, 2010 | Goodman CKL30AR30 Air Conditioner

2 Answers

Im not getting enough cold air in my house to keep it cool during the day my air runs 24/7 but it remains hot the only time it cools down is at night

Hi, I will give you some things you can do as far as some service on this unit. What happens, is when the ambient temperature rises, so does the internal freon pressures in the system which in turn, causes the unit to work much harder and at a 95f degree ambient temperature, most all residential units loose up to 45 to 50% of there efficiency!! This is a fact. Then you walk into a shopping center and its over 100 plus outside and a nice 72degrees inside, so you start wondering why my unit is not that cool. Well, being a A/C, Heating, & Refrigeration Contractor for 33 years, I know what goes on. Most all home units as I say are made to work good up to about 95 degrees ambient. This is for a 2 to 5 ton unit. 1 ton of cooling is 12,000 btu's, while on the roof of these shopping centers and strip malls they have 15, 25, 75, and even higher tonnage units!! So back to yours, I just wanted you to learn a little about the size and tonnage of a unit. You can do this first. It's showing you have a complete package unit, all in one not a split. I don't know when the last time you had it serviced but, take your garden hose, kill the power to the unit first. Go to the unit and the wrap around coil give it a good washing out. They make a coil cleaner but you have to be a contractor to buy it. Water will be fine. This should be done once a year in the Spring. Careful not to bend the aluminum fins flat on this coil, but do clean it very well. Dirt is drawn in by the condenser fan motor on top. Start washing from the fan area out first, and go around the outside and wash in. Do this until you see no more dirt, as this is very important. This keeps the high head pressures down to normal in your system, and if its dirty you can lower this high side pressure up to 100 p.s.i. The unit is made for outdoors, so don't worry about getting it wet. Try not to spray water on the main electrical box of course. Keep your filter cleaned or changed as this is also very important. Here is a rule of thumb I will tell you about air conditioning temperature you will know. If you can, pick you up a dial or digital type pocket thermometer at a hardware store, and take these readings at the supply air vents,1 or 2 of them and record it, and at the return air which is where the air returns back through your air filter. This is called your temperature split, or TD (temperature difference). If your unit is running properly as far as freon charge and so on, it should be between 18f to 25f degree difference!! Any higher or lower indicates a problem, low on freon, compressor valves are weak, plugged evaporator coil or dirty filter, many things, dirty condenser coil. Check this before you wash out your coil and let it run and dry out first, and recheck to see what you have. Your unit runs 24/7 trying to capture the load and can't keep up. May be do to age, or just needs some TLCare. So again, the TD check, lets say your supply air coming in is 58*F. Your return should be close to 76*F to 83*f, a 18 to 25*F degree difference. 18*F to 20*F would be awesome, but this is the rule of thumb we use. If it's 105* outside, you will be lucky to have a indoor temperature of 80*F!! A 25* difference. If after recording all of your temperatures and noting them, cleaning the condenser coil and making sure the filter is clean, after the unit runs for 1/2 an hour, recheck the sa&r/a and see what you have. If the coil was very dirty, this may have solved your problem. If after all of this, you may need to have your freon level checked, lets hope not. I have a feeling that it is in need of a good service. Please keep me posted on this, and I am sorry for such a long answer, but I just wanted to share some things with you to remember. Please get back to me to let me know the out come and please rate me kindly as I know you will.
A/C, Heating, & Refrigeration Contractor

Jul 29, 2010 | Intertherm P3RA-048K Air Conditioner

1 Answer

Air conditioner is tripping after one hour

clean filter and Evap coil and condensing coil. also some units have a gfi breaker at the plug witch some times go bad

Apr 08, 2010 | Samsung AW1203B Air Conditioner

1 Answer

Conia 3 HP, 5 yr old air con/ condensation from wall unit


Nov 30, 2009 | Heating & Cooling

2 Answers

LG 3phase ducted CH02 fault (internal pipe thermistor error)- every day. When it comes up the air con shuts off, and takes a few hours to clear itself. Very annoying. I notice though it comes up less if i...

have u checked your low pressure and high pressure when compressor is on. Remember the compressor has a thermal protection switch if the compressor has too much freon the A.C will work for a while turn off, then turn then off and on. Are the air filters for the evaporator clean, is the blower fan blowing the correct way. How long ago did the evaporator coil got cleaned. With a properly cleaned filter and evaporator coil you can now check for pressures. Use your ammeter and check how much the compressor is pulling and compared it to the name plate. How much tons your A.C. If you give me how much tons and low and high readings I might help you diagnose the problem. Make sure the evaporator is clean blower blowing correct way condenser cleaned and condenser fan rotating the correct way

Jul 24, 2009 | Heating & Cooling

1 Answer

I have LG 1.5 Ton split ac-2 year old never serviced,now cooling reduced. May we self service the same.

The only service you can do is change filters clean the dran and wash off the outside coils. Sorry Rsuty

Jun 13, 2009 | LG Heating & Cooling

1 Answer

Extremely long time to get cool air with 5 ton 13 seer goodman heat pump which is 3 years old.

Check your filter. Make sure it is clean. Make sure the outdoor unit is operational. (power on). Clean your condenser coil with a garden hose. If possible check your evaporator coil. If it is dirty clean it. Your furnace (or air handler) blower speed should be set on high. All of your registers (supply & return) should be open and unobstructed. Check for proper thermostat settings. If none of this information solves your problem , then your units charge needs to be checked. You could be over or undercharged with freon.
Good luck......

May 06, 2009 | Goodman Heating & Cooling

3 Answers

Compressor will not start.

Usually short cycling means that High side pressure is getting to high (due to not working condenser fan, or dirty condenser coil), or low side pressure is getting too low (might have low level of freon or restriction in sealed system). low side would drop dramatically if indoor blower is not running, so if air is not circulating thru evaporator coil, coil will freeze up and low side would be much lower then normal. Here is video how I found issue with package AC not coming on. Thermostat call for cool, but condenser would not come on, indoor blower runs ok.

Nov 02, 2008 | Ruud UAMB Air Conditioner

2 Answers

Carrier air handler tonnage?

That is a fairly large difference. It is usually ok to have the inside evap. coil and blower up to 1 ton larger than the outside condenser. That will make the unit slightly more efficient as well as less likely to freeze up on low airflow situations. It is not recommended to install a new condenser on an old evap coil. There has been a lot of changes to the design of the coils in the last little while. For example a 10 year old 2 ton coil may only have 3 cubic feet of volume but a new 2 ton coil may have 4 cubit feet of volume.

There are many factors that may have infulenced the decision on what size condenser to install. Many of which can only be done by visiting the home and doing alot of work, checking the duct sizing bioth supply and return, inspecting the insulation and windows of the home etc. etc. Most of the time that never gets done. You can blame the contractor for not doing a complete check, but at the same time you can blame the customer because many contractors that are that good loose the job to a cheaper bid that did not no any of the research. It is a catch 22 for everyone involved.

There is ALOT more to sizing equipment that many people think, sadly that also includes many HVAC contractors. Way too many people use "rule of thumbs" or flat out "guess".

Sorry for the rant but your queston can only be answered by a good well educated HVAC contractor visiting your home. That type of a contractor is getting hard to find these days in such a price competetive world.

Oct 14, 2008 | Carrier Heating & Cooling

Not finding what you are looking for?
Heating & Cooling Logo

103 people viewed this question

Ask a Question

Usually answered in minutes!

Top Whirlwind Heating & Cooling Experts


Level 2 Expert

388 Answers

Dennis Boxerman

Level 3 Expert

1266 Answers

Bill Long

Level 3 Expert

588 Answers

Are you a Whirlwind Heating and Cooling Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides