Please Help me(yet again) - cooling problems

[timdrag]

Ive got a 1350 sqft house and i just had a trane variable speed air handler and an sb13 3 ton unit installed. It replaced a really old Comfortmaker 3 ton

I can not get the house below 74-76 with the new system. The system runs non-stop. I could make the house an ice chest with the Comfortmaker. The Trane tech has been here 3 times and replaced the txv valve, and replaced the refrigerant filter every time with larger and larger filters as well as recharging the system every time. He claims the air coming straight out of the handler is 66 degrees(i dont think it can be) on the 85 degree day that we had today. The installer claims that I should only expect 74 degrees in the house on a 85 degree day. Well then why do I have air conditioning?!

So here are my questions:

1: What temp should the air be coming out of the registers on an 85 degree day?

2: Do I have a bum unit?

3: The installer is trying to tell me that he may need to take out the 3 ton and put in a 3.5 ton(with me paying the difference of course) to properly cool the house. Why did the old 3 ton do a great job compared to this one?

All responses are greatly appreciated.

[andserco]

Because Comfortmaker is better than Trane.......LOL...just kidding..:D

Could you post model numbers of outside unit and indoor....


What is you location?

[bmathews]

I think you need to get the company to send out somebody else. A 3 ton whether be rule of thumb or manual J is plenty and probably too much a/c. The design conditions for hvac systems are 75 degrees inside on a 95 degree day. Do you turn the unit off all day when you leave? What is the temp when you get home if so. Are all the dip switches set correctly on the air handler? The temperature of the air when it is whatever outside really means nothing. The temperature coming out of the registers should be 15-20 degrees colder than the temperature in the house. Usually at least 17-20. It sounds to me like you might have some ductwork issues. Putting a 3.5 ton is frickin' ridiculous and will not solve your problem, it will actually make it worse. You need to get somebody else from their company out to evaluate. Or pay another company out to evaluate if you can't get anything from your installer. Or live with what you have. You might have some recourse through the state licensing agency if you have one in your state.

[timdrag]

Thanks for the responses.

Some answers to your questions:

1- The air coming out of the duct at the registers is 72-74 degree air. Temp in house would be 78 from the start.

2- Model numbers: 2tee3f37a100aa
2tbb3036a1000aa

3- Im in Northern NJ

ps: i do have 5 year parts and labor from Trane so im tempted to demand a new system

[ACFIXR]

Ive got a 1350 sqft house and i just had a trane variable speed air handler and an sb13 3 ton unit installed. It replaced a really old Comfortmaker 3 ton

I can not get the house below 74-76 with the new system. The system runs non-stop. I could make the house an ice chest with the Comfortmaker. The Trane tech has been here 3 times and replaced the txv valve, and replaced the refrigerant filter every time with larger and larger filters as well as recharging the system every time. He claims the air coming straight out of the handler is 66 degrees(i dont think it can be) on the 85 degree day that we had today. The installer claims that I should only expect 74 degrees in the house on a 85 degree day. Well then why do I have air conditioning?!

So here are my questions:

1: What temp should the air be coming out of the registers on an 85 degree day?

2: Do I have a bum unit?

3: The installer is trying to tell me that he may need to take out the 3 ton and put in a 3.5 ton(with me paying the difference of course) to properly cool the house. Why did the old 3 ton do a great job compared to this one?

All responses are greatly appreciated.
never mind.

[udarrell]

The unit is unlikely to be bum; other factors could make its performance BUM.

I believe U say its a 13-SEER, right?
R-22 or R-410A system?
With a TXV the mild outdoor temp won't have much influence on the indoor temp-split unless there is a high humidity -with a high rate of moist air infiltration into your home.

What's the % relative humidity in your home?
Get a humidity gage & keep a record of the humidity & Temps.

High humidity will put a heavy latent load on the evaporator -lowering temp split-indoors, & also raise the temp-spit from the outdoor condenser above the outdoor temp.

Provide me with the SEER-13, right; Humidity in home; split from SA/RA in home, & the temp split off, "a top discharge condenser."

This will provide some data on the system providing some clues for us.

Does the indoor airflow seem as strong as the old system?
Could the Return air be pulling air from a hotter attic or garage, -now?

There are more reasons for it not to have a greater indoor temp-spit than I will list here. *(My Fingers R problem= Typo-corrections!)

Is the evaporator a Rated match with the condenser?

It may have something to do with the install; but I'd rather not go there at this time. Click my name above & U can get in touch with me.

[bmathews]

Thanks for the responses.

Some answers to your questions:

1- The air coming out of the duct at the registers is 72-74 degree air. Temp in house would be 78 from the start.

2- Model numbers: 2tee3f37a100aa
2tbb3036a1000aa

3- Im in Northern NJ

ps: i do have 5 year parts and labor from Trane so im tempted to demand a new system

Demanding a new system will likely get you nowhere. Most of the time, you will not get a new system. They will send a Trane rep out first. Did the installing company recommend any ductwork changes or anything else that you declined? If so, you need to fix those issues. If the ductwork is bad, that will need to be fixed before any new system can even be considered being installed.

[jstjohnz]

Ive got a 1350 sqft house and i just had a trane variable speed air handler and an sb13 3 ton unit installed. It replaced a really old Comfortmaker 3 ton

I can not get the house below 74-76 with the new system. The system runs non-stop. I could make the house an ice chest with the Comfortmaker. The Trane tech has been here 3 times and replaced the txv valve, and replaced the refrigerant filter every time with larger and larger filters as well as recharging the system every time. He claims the air coming straight out of the handler is 66 degrees(i dont think it can be) on the 85 degree day that we had today. The installer claims that I should only expect 74 degrees in the house on a 85 degree day. Well then why do I have air conditioning?!

So here are my questions:

1: What temp should the air be coming out of the registers on an 85 degree day?

2: Do I have a bum unit?

3: The installer is trying to tell me that he may need to take out the 3 ton and put in a 3.5 ton(with me paying the difference of course) to properly cool the house. Why did the old 3 ton do a great job compared to this one?

All responses are greatly appreciated.

1) The air temp from the vents is more dependent on the inside temp than the outside temp. What was the inside temp when you had 66 degrees at the air handler supply side?

2) Something's not right.

3) Adding an extra half-ton isn't going to make much of a difference. They need to figure out what's wrong with the system you have. If the tech is competent he can figure out how many tons of cooling you are actually getting.

You say he replaced the TXV once, what did he do the other times? If the filter-drier is actually clogging up that may be an indication that there's junk in the lines, possibly due to bad installation practices. Did they reuse the old lineset or install new? Is the new unit R22 or R410A?

[meoberry]

Thanks for the responses.

Some answers to your questions:

1- The air coming out of the duct at the registers is 72-74 degree air. Temp in house would be 78 from the start.

2- Model numbers: 2tee3f37a100aa
2tbb3036a1000aa

3- Im in Northern NJ

ps: i do have 5 year parts and labor from Trane so im tempted to demand a new system

First I doubt that Trane will replace unit. They would expect the dealer to properly diagnose poblem which they have not done. You only have a 5 to 8 temp. drop. which would indicate: a heat strip on, pulling outside air into the return, or some type of refrigeration problem. If you have 78* inside air you should have between 58* to 63* air at the top of the coil depending on inside humidity. Your temp drop should be measured at the bottom of the coil or return temp and the top of the coil supply temp. Air temp coming out of the ducts or vents have to many varibles to calculate for a proper temp. drop. But usually I have seen a temp drop from return to duct or vent to be 10* or better. I would be raising cane for the contractor to get someone out there to find and fix problem and maybe calling manufacturer and complaining to them. This wiil put heat on contractor. Its best to contact the wholesaler. I don't know who that would be in your area. Just check local phone book.:eek:

[timdrag]

Thanks again for the replies.

Some answers to your questions:

The interior temp of the house was 78 when they first turned it on. The coolest it got was 74 in the house. External temp was 85 degrees.

Unit is r22

The other visits allegedly were a line flush and new filter/dryer. Im just short of a beer keg sized filter at this point(im exaggerating but it is big)

I was/am willing to do the ductwork. But the old system with the current ductwork would get the house down to 68 no worries on any day.

Humidity in the house is 46%

13 seer unit.

Old system was a 3ton comfortmaker(15 years old) that could make the house 66 if I needed it to on any day.

I think that covers it. If i missed anything I will reply asap. I wish I had the knowledge to speak intelligently to the Trane guy, so im hoping everyone can give me some ideas.

I really need this working correctly.

[timdrag]

Thanks for the response. No heat strip. We have hot water baseboard.

They've admitted to me that the temp drop is less than it should be coming out of the registers.

I guess I can call the wholesaler. The owner is coming by tomorrow and i'll bend his ear. It sounds like from you gentlemen that this is not normal. Im making a list of your responses to present to him.

[udarrell]

Thanks again for the replies.
Some answers to your questions:
The interior temp of the house was 78 when they first turned it on. The coolest it got was 74 in the house. External temp was 85 degrees.

Unit is r22
The other visits allegedly were a line flush and new filter/dryer. Im just short of a beer keg sized filter at this point(im exaggerating but it is big)

I was/am willing to do the ductwork. But the old system with the current ductwork would get the house down to 68 no worries on any day.

Humidity in the house is 46%; 13 seer unit.
Old system was a 3ton comfortmaker(15 years old) that could make the house 66 if I needed it to on any day.

I think that covers it. If i missed anything I will reply asap. I wish I had the knowledge to speak intelligently to the Trane guy, so im hoping everyone can give me some ideas.
I really need this working correctly.
Okay, this is NOT written in Stone & could vary some with your equipment!
These are figures from a Goodman 3-Ton condenser/ 4-Ton evaporator coil, piston metering device; R-22, 13-SEER setup: 75-IDB - 66-IDB= 9-F Split at 46% Relative humidity, WB is about 62.5-F.

Reading chart @ 63-IWB produces a 18-F indoor split @ 1432-CFM. It appears it may be getting around half its indoor design split. At 1116-CFM the split is 19-F & 30,700-BTUH; nominal BTUH always varies with the load, especially the humidity latent load. (This is different equipment!)

At the above figure with Outdoor temp at 85-F, the condenser split with head @190, SCT of 98-F -85= 13-F condenser temp split. It could be as low as 10 or 11-F with a lower indoor CFM at 42% RH.

Now, if the condenser split is considerable above 13-F at around 1400-CFM indoor airflow, probably @1200-CFM or less; then there is hot air entering the E-Coil intake from attic or garage, etc.

If condenser temp-split is a lot lower, then there is insufficient load on the E-Coil or the refrigerant system has a major problem that must be found & remedied.

Okay, what were the superheat & Sub-cooling Temps figures?
If they don't take those readings go to my pages, if necessary giv'em a hard copy, they need that information data because it tells U where the refrigerant is in the system & what it is doing.

TXV sub-cooling should be within+/- 2 degrees of installation instructions
Properly operating unit will be within 3 degrees of the indoor split; within +/- 10-psig of listed high-side pressure.

Condenser AMPS within 3 Amps of the typical value shown; & within 5 degrees of suction pressure listed for those specific conditions - Darrell

[beenthere]

If the air handler is in the attic.
Ask them to check for leaks in the return pulling in attic air.

Ask them to send out a different tech then the one they have been sending.

Ask for them to take refrigerant pressure readings and line temps.
Along with the air handlers enetering and leaving air wetbulb temps.
Ask them what CFM the blower is set for. And what static pressure the system is operating at.

[timdrag]

Thanks to everyone for their insight. As always is the case the "kiss" Principal prevailed. I called the owner of the company and asked him to come over and personally check the system. Told him he would need to provide me with a schedule j proving that I needed a 3.5 ton before I agreed to themes unit and that I wantedvthis one fixed.

After taking all these pressure reading and the like he was stumped. He started crawling around the attic
looking at the air handler and voilà he found the problem.

The aprilaire filter is wider than the air handler intake(roughly 30 percent larger). When his installers fit the aprilaire(2210). To the air handler they didn't seal off the extra 30% of the filter area from the attic. So basically the system was sucking 30% unaidconditioned attic air. This would explain an almost nil temp differential. He's coming back Tuesday to seal the hole properly. There's a piece of cardboard there now as a temp patch and the difference is night and day.

[beenthere]

Ask them to recheck the charge when they fix the air leak properly.

They may have tried adding gas to get it cooler, and have it overcharged now.

[timdrag]

I will. I also know that they mentioned that they had messed with the fan speed so i will ask them to check that too.

[udarrell]

Thanks to everyone for their insight. As always is the case the "kiss" Principal prevailed. I called the owner of the company and asked him to come over and personally check the system. Told him he would need to provide me with a schedule J proving that I needed a 3.5 ton before I agreed to themes unit and that I wanted this one fixed.

After taking all these pressure reading and the like he was stumped.(?) He started crawling around the attic looking at the air handler and voilà he found the problem.

The Aprilaire filter is wider than the air handler intake(roughly 30 percent larger). When his installers fit the aprilaire(2210). To the air handler they didn't seal off the extra 30% of the filter area from the attic. So basically the system was sucking 30% unaidconditioned attic air. This would explain an almost nil temp differential. He's coming back Tuesday to seal the hole properly. There's a piece of cardboard there now as a temp patch and the difference is night and day.

This case is an example of why the Condenser-Temp is so important; for Techs the pressure/temp is easily read on the manifold gage.

It shows U whether the Indoor latent, sensible & airflow CFM load is consistent with the outdoor heat discharge load.

Non-techs can use a TH to check the temp split; compare that to the indoor humidity & temp split & you may need to call a Tech to check the system.

My prior post:

Now, if the (outdoor) condenser split is considerable above 13-F at around 1400-CFM indoor airflow, probably @1200-CFM or less; then there is hot air entering the E-Coil intake from attic or garage, etc.

The condenser temp-split incorporates both the latent humidity condensation heat load & the sensible heatload.

A high indoor humidity will raise the condenser temp split. Then you need to know the indoor airflow CFM to see if the 4-way equation is in balance.

Any time you have the mfg'ers head pressure listing at specific conditions that pressure can easily be converted to the discharge temp of your condenser & comparisons made.

Knowing & using the condenser temp-split is key to identifying where the problems exist, & ought to be read on the gages & used effectively by every Tech!

HO use a TH, You'll then need to call a service Tech to further trouble shoot the entire system & remedy the problems for optimal efficient operation! - Darrell

[Shophound]

Thanks to everyone for their insight. As always is the case the "kiss" Principal prevailed. I called the owner of the company and asked him to come over and personally check the system. Told him he would need to provide me with a schedule j proving that I needed a 3.5 ton before I agreed to themes unit and that I wantedvthis one fixed.

After taking all these pressure reading and the like he was stumped. He started crawling around the attic
looking at the air handler and voilà he found the problem.

The aprilaire filter is wider than the air handler intake(roughly 30 percent larger). When his installers fit the aprilaire(2210). To the air handler they didn't seal off the extra 30% of the filter area from the attic. So basically the system was sucking 30% unaidconditioned attic air. This would explain an almost nil temp differential. He's coming back Tuesday to seal the hole properly. There's a piece of cardboard there now as a temp patch and the difference is night and day.

I'm aghast. Prior to the owner's visit, the tech's solution was to keep increasing the drier size? He kept doing the same thing even if it did NOTHING to improve your situation? The owner then visits and finds the real source of the problem.

I'm with beenthere. Now that the return air leakage will be resolved soon, a recheck of the refrigerant level and system performance is in order. Insist the owner return to do it, since apparently he's a better troubleshooter than his installer or tech.

[meoberry]

This case is an example of why the Condenser-Temp is so important; for Techs the pressure/temp is easily read on the manifold gage.

It shows U whether the Indoor latent, sensible & airflow CFM load is consistent with the outdoor heat discharge load.

Non-techs can use a TH to check the temp split; compare that to the indoor humidity & temp split & you may need to call a Tech to check the system.

My prior post:


The condenser temp-split incorporates both the latent humidity condensation heat load & the sensible heatload.

A high indoor humidity will raise the condenser temp split. Then you need to know the indoor airflow CFM to see if the 4-way equation is in balance.

Any time you have the mfg'ers head pressure listing at specific conditions that pressure can easily be converted to the discharge temp of your condenser & comparisons made.

Knowing & using the condenser temp-split is key to identifying where the problems exist, & ought to be read on the gages & used effectively by every Tech!

HO use a TH, You'll then need to call a service Tech to further trouble shoot the entire system & remedy the problems for optimal efficient operation! - Darrell

All true would be simpler if the tech would have noticed the suction was high and the s/h was too low for inside air temp.:rolleyes:

[catmanacman]

I'm aghast. Prior to the owner's visit, the tech's solution was to keep increasing the drier size? He kept doing the same thing even if it did NOTHING to improve your situation? The owner then visits and finds the real source of the problem.

I'm with beenthere. Now that the return air leakage will be resolved soon, a recheck of the refrigerant level and system performance is in order. Insist the owner return to do it, since apparently he's a better troubleshooter than his installer or tech.

this drier is it in the line outside of the unit or are they replacing the drier inside the unit all Trane units have a drier inside of the outdoor unit and it should be replaced if the system is opened

[Shophound]

this drier is it in the line outside of the unit or are they replacing the drier inside the unit all Trane units have a drier inside of the outdoor unit and it should be replaced if the system is opened

If an additional liquid line drier is installed outside of the condensing unit, good practice would dictate removing the original factory drier inside the unit. The tech has the option of either replacing the original drier like for like, or removing it and installing a liquid line drier. Leaving two driers in the system can restrict refrigerant circulation more than necessary.

[udarrell]

All true would be simpler if the tech would have noticed the suction was high and the s/h was too low for inside air temp.:rolleyes:
I didn't see where Superheat was checked.

It is drawing a lot of hot air from the attic, I think you meant to state that s/h -> Super Heat would be too high. I saw no SH data listed, it would have been a good indicator clue.

For the indoor room Return Air temp & humidity readings, indoor temp-split, if CFM is okay, was way below what mfg'ers data states.

I thought I listed the mfg'ers listed split for that unit, maybe not, anyway a 13-SEER at an Indoor 50% RH or say a 63-IWB 75-IDB you could ball park it at close to 18-F or 19-F. - Darrell