Heat Pumps and Electric Heating - Heat pump won't cool, fan doesn't run sometimes
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rfmann
08-28-09, 07:41 AM
I had a new 2400ft2 house built last year, (2) brand new 3 ton heat pumps installed, one for the main floor and one for the upstairs.
The one for the main level has been working great, no issue there.
However, the one for the upstairs has been giving me heartburn since day one.
A little history, last summer I had the Heat pump installers (a no name lowest-bid company that the contractor of our house hired) come out to the house about a dozen times because it was not cooling to the same capacity of the other one.
The upstairs would only put out semi-cool, semi humid air. The first time out they replaced the compressor, that did not fix it. The next time they came out, they said it had too much coolant, they let some out and left it worked fine for a day or two, the next time they came out, they said it needed coolant, they put some in it and it worked fine for a day or two, this it has too much and it has too little coolant escapade went on every week for the until the end of cooling season.
I figured that there is more than they are telling me and that they knew what it is but have chosen to string us along until the warranty ran out, to relieve them of costly warranty work.
Guess what, the warranty is up. Fast forward to today. The temperature have been tolerable for the most part so we decided to deal with the don't cooling as much as it should for the time being until we can afford to get it fixed.
Well we had a couple of 90 degree days and that is when the thing just goes nuts and it gets rather miserable upstairs. Hot and Sticky and Humid. The line out side at the heat pump that should be cold and sweaty remains ambient temperature and dry as a bone.
Again, all summer all I heard was it has too much coolant or it has too little coolant. If it was holding too much then it pretty much tells me that it must not be leaking out, right?
It also has a new thermostat. So a new compressor, new thermostat, based on what I've been told all summer I am assuming no leaks in the lines, what else could be going wrong here. There is a second issue that is going on, every once in awhile the fan decides it just doesn't want to come on even though the heat pump outside is running full force, so needless to say inside never cools down so the heat pump never shuts off.
You cut the heat pump off. I assume maybe a relay could be sticking. If anyone has any information that can help me, I would greatly appreciate it. I am an industrial controls electrical engineer by profession, so I can understand anything electrical and mechanical that you have offer.
I am just unfamiliar with the science of Heat pump designs is all. With out schematics I don't see the whole picture, but I am sure that if I got to poking around in it. It would all start to make sense to me. So feel free to get technical, I will be able to understand. Thanks, Ray
The one for the main level has been working great, no issue there.
However, the one for the upstairs has been giving me heartburn since day one.
A little history, last summer I had the Heat pump installers (a no name lowest-bid company that the contractor of our house hired) come out to the house about a dozen times because it was not cooling to the same capacity of the other one.
The upstairs would only put out semi-cool, semi humid air. The first time out they replaced the compressor, that did not fix it. The next time they came out, they said it had too much coolant, they let some out and left it worked fine for a day or two, the next time they came out, they said it needed coolant, they put some in it and it worked fine for a day or two, this it has too much and it has too little coolant escapade went on every week for the until the end of cooling season.
I figured that there is more than they are telling me and that they knew what it is but have chosen to string us along until the warranty ran out, to relieve them of costly warranty work.
Guess what, the warranty is up. Fast forward to today. The temperature have been tolerable for the most part so we decided to deal with the don't cooling as much as it should for the time being until we can afford to get it fixed.
Well we had a couple of 90 degree days and that is when the thing just goes nuts and it gets rather miserable upstairs. Hot and Sticky and Humid. The line out side at the heat pump that should be cold and sweaty remains ambient temperature and dry as a bone.
Again, all summer all I heard was it has too much coolant or it has too little coolant. If it was holding too much then it pretty much tells me that it must not be leaking out, right?
It also has a new thermostat. So a new compressor, new thermostat, based on what I've been told all summer I am assuming no leaks in the lines, what else could be going wrong here. There is a second issue that is going on, every once in awhile the fan decides it just doesn't want to come on even though the heat pump outside is running full force, so needless to say inside never cools down so the heat pump never shuts off.
You cut the heat pump off. I assume maybe a relay could be sticking. If anyone has any information that can help me, I would greatly appreciate it. I am an industrial controls electrical engineer by profession, so I can understand anything electrical and mechanical that you have offer.
I am just unfamiliar with the science of Heat pump designs is all. With out schematics I don't see the whole picture, but I am sure that if I got to poking around in it. It would all start to make sense to me. So feel free to get technical, I will be able to understand. Thanks, Ray
Jay11J
08-29-09, 07:47 PM
Something is going on here.
But, first thing I'd like to know is what is the make and model #'s of both indoor unit and outdoor unit.
My guts says something is not matching.
But, first thing I'd like to know is what is the make and model #'s of both indoor unit and outdoor unit.
My guts says something is not matching.
rfmann
09-07-09, 07:34 AM
Sorry for taking so long to respond.
BTW, Please forgive me for giving wrong ifo on the size of the heatpump.
Correction: I actually have 2.5 Ton Units and not 3 Ton
The outside unit is a Gibson JT5BU-030KA
The in attic handler unit is a Gibson GB5BM-030K-A.
I noticed that the line at the air handler in the attic is cold and sweety, however, at the heat pump outside, it is dry and ambient temp.
Also we have noticed that the fan not coming on is usually on the hottest of days, we simply cycle on and off and all is well for a day or so.
BTW, Please forgive me for giving wrong ifo on the size of the heatpump.
Correction: I actually have 2.5 Ton Units and not 3 Ton
The outside unit is a Gibson JT5BU-030KA
The in attic handler unit is a Gibson GB5BM-030K-A.
I noticed that the line at the air handler in the attic is cold and sweety, however, at the heat pump outside, it is dry and ambient temp.
Also we have noticed that the fan not coming on is usually on the hottest of days, we simply cycle on and off and all is well for a day or so.
Jay11J
09-07-09, 07:09 PM
Ok, everything seems to match between the two units.
Do you know if the tech had looked at the charging chart? (or superheat)
How long of a run is there between the Air handler and unit outside?
What fan are we talking about? Inside or outside?
Do you know if the tech had looked at the charging chart? (or superheat)
How long of a run is there between the Air handler and unit outside?
What fan are we talking about? Inside or outside?
rfmann
09-08-09, 06:23 PM
I do remember hearing the tech say something about Superheat. He explained it all to me but I can't remember all the details but he did seem satified with the readout.
The airhandler is about 35-40ft over and about 20-25ft up from the outside unit.
Could the air handler be too far away. The house is about 40 x 27 The heatpump is on the right side of the house at basement floor level. The air handler is on the opposite end of the house all the way up in the attic.
FYI, there is a finished bonus room above garage that this airhandler also services. And there is a return vent in that room.
The subject fan is the Air Handling fan inside the house. Still tends to want to stick in the off position until I cycle off and then back on, then it starts running....My thoughts are possibly a relay sticking here.
The airhandler is about 35-40ft over and about 20-25ft up from the outside unit.
Could the air handler be too far away. The house is about 40 x 27 The heatpump is on the right side of the house at basement floor level. The air handler is on the opposite end of the house all the way up in the attic.
FYI, there is a finished bonus room above garage that this airhandler also services. And there is a return vent in that room.
The subject fan is the Air Handling fan inside the house. Still tends to want to stick in the off position until I cycle off and then back on, then it starts running....My thoughts are possibly a relay sticking here.