mystery problem please help

[floridatech100]

Hi i am a tech in florida and i have recently ran into a unit that is just pushing me to the limits trying to fix it. Its a 4 ton carrier 13 seer straight cool (just changed by me ) previously it had a 4 ton coleman any who we changed it due to a freon leak and its age. Well now that its changed the customer keeps calling and saying it cools at night/mourning but not in the heat of the day. i have been there during the hottest parts of the day and it indeed can not keep up the temp just keeps rising. I did a split test yesterday and it had a 19-20 degree split, yet it wont come down in temp when its 95ish out. My first quess was its undersized but she said the 4 ton colman use to be very good at keeping up also this is your adverage doublewide so i would think its plenty. Any ideas? Thanks

Also on a side note.. has anyone else noticed a rash of problems with carrier/bryant/paynes blower wheels on 5ton package systems? I started noting that the wheels would fall apart back in the day with the 10 seer zp models and the problem still seems to be there with the new 13 seer designs (only on te 5 tons) Note:we always make sure there is 14 inch duct for both return and supply..

[skippedover]

Did you do a load analysis on the home before the new sytem was spec'd? If you did a load analysis and then chose the replacement unit using Manual 'S', you shouldn't be having any problem unless there's a mechanical issue. You've not supplied any info regarding suction/head pressures, pressure reducing device, superheat, subcooling numbers, static pressures, compressor amps. Get a little more technical and you might get some good answers but just a TD across the indoor coil isn't nearly enough.

[smokin68]

Check your airflow first, then check the system's charge, it could be anything. Doubt it's undersized....windows open or something silly like furniture blocking returns/supplies?

[ARPA]

floridatech100:

Welcome to what is IMO one of the best teachers you are going to have in this field!

HVAC-TALK.

But, there are rules, and one of those is no DIY, not saying you are or not, but you are posting as a regular member and in an open forum, residential where tech things can not be posted.

Read up on how to become a pro member, it's FREE!

[the dangling wrangler]

If it's a mobile home look closely at your duct work. Seen a few with broken , leaky , and in general , garbage ducting. I guess this could apply to a real house also. I've happened across some brand new units with intermittent problems with contactors not pulling in right also. Don't forget to look at the supply grills . Maybe open them up a bit with needle nose pliers.

[allstar08]

If it's a mobile home look closely at your duct work. Seen a few with broken , leaky , and in general , garbage ducting. I guess this could apply to a real house also. I've happened across some brand new units with intermittent problems with contactors not pulling in right also. Don't forget to look at the supply grills . Maybe open them up a bit with needle nose pliers.

Ditto.. look at the crossover if it is a double.

[the dangling wrangler]

About those blower wheels. Yes , I've had many just "blow apart" That's when Carrier fell out of favor with me. and what does Carrier give you for a replacement? The same dad -gum wheel. Go figure. You should hear the sound they make before they self destruct.

[CHEVY04]

can someone give me some info on becoming a pro memeber

[the dangling wrangler]

Yes, you ought to try it , it's grrrrreat. You need to apply to one of the mods.They can tell you more. Try the contact us at the bottom of every page . (You do know the secret hand shake, right??)