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clawrence
07-28-2016, 03:03 PM
I installed a 3ton RUUD RH1T3617STANJA Air Handler with a 2.5ton RA1430AJ1NA Condenser to get 15.5 SEER.

My question is what should be the final Sub-Cool R-410A Charge be set at in degrees at 90 degrees ambient ?

The condenser notes 8 degrees sub-cool 2.5ton My Condenser
and if it was a 3ton sub-cool would be 15 degrees
Just remember this is a 2.5condenser matched to 3ton air handler

I have set the air handler blower speed lower the name plate on air handler said to do this for 2.5tons
It was set at 5 from factory. I have set it to 3

My question is what should be the final Sub-Cool R-410A Charge be set at in degrees at 90 degrees ambient ?

ksefan
07-28-2016, 03:14 PM
8 should be fine, is this your first install?

ksefan
07-28-2016, 03:16 PM
Did you check the indoor static pressure, or just guess on airfow?

clawrence
07-28-2016, 03:18 PM
Yes,
It's I have tech's saying match condenser some saying match air handler
I set it to 10degrees sub-cool unit has a TXV
I take a while for it to settle down.
I did put a sight glass at air handler it flashes too

ksefan
07-28-2016, 04:23 PM
After 15 min runtime what was superheat and subcool?

Poodle Head Mikey
07-28-2016, 04:28 PM
How are and where are you measuring the subcooling?

PHM
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I installed a 3ton RUUD RH1T3617STANJA Air Handler with a 2.5ton RA1430AJ1NA Condenser to get 15.5 SEER.

My question is what should be the final Sub-Cool R-410A Charge be set at in degrees at 90 degrees ambient ?

The condenser notes 8 degrees sub-cool 2.5ton My Condenser
and if it was a 3ton sub-cool would be 15 degrees
Just remember this is a 2.5condenser matched to 3ton air handler

I have set the air handler blower speed lower the name plate on air handler said to do this for 2.5tons
It was set at 5 from factory. I have set it to 3

My question is what should be the final Sub-Cool R-410A Charge be set at in degrees at 90 degrees ambient ?

clawrence
07-28-2016, 04:58 PM
I ran unit for an hour
Took it at liq line king valve.
Temp 6" from valve

beenthere
07-28-2016, 05:00 PM
Have your company send a journeymen tech with you, and go over how to set up equipment.

clawrence
07-28-2016, 05:04 PM
I just want to know if anyone has installed a unit with R-410a on
A unit with a evap coil that is 1/2 ton larger to get higher SEER
And what was your final sub-cool
Degrees

clawrence
07-28-2016, 05:06 PM
Or did you just set sub-cooling to condenser chart?

beenthere
07-28-2016, 05:14 PM
I just want to know if anyone has installed a unit with R-410a on
A unit with a evap coil that is 1/2 ton larger to get higher SEER
And what was your final sub-cool
Degrees

Done 1/2 ton, and 1 ton larger. And as you should know. It varies with the unit. Have a journeymen go out with you.

clawrence
07-28-2016, 05:20 PM
Thank you for no help
I am the tech
Asking question on an open forum please don't help anymore

rsmith46
07-28-2016, 06:21 PM
You have to get the airflow right before you check charge. Do you know how to check total external static pressure and use fan curve chart to get CFM's?
Especially when you use a 3 ton air handler with 2.5 ton condenser, I don't sell Rudd but who matched the equipment to get 15.5 SEER from a 14 SEER condenser?

beenthere
07-28-2016, 06:24 PM
Thank you for no help
I am the tech
Asking question on an open forum please don't help anymore

You may be the tech. But you are not the journeymen tech.

Most of us, have had to have a journeymen tech show us things while we were learning. Never be too proud to ask one of the journeymen techs you work with for help.

rsmith46
07-28-2016, 06:27 PM
Yes,
It's I have tech's saying match condenser some saying match air handler

I did put a sight glass at air handler it flashes too

You said you were the tech, what do you mean the sight glass is flashing too?

You'll be lucky to get 12 SEER out of system if not set up properly.

HVAC_Marc
07-28-2016, 06:27 PM
8, cookie, purple, potato.

clawrence
07-28-2016, 06:40 PM
RUUD matched the system
You can look up Google RUUD RA14
The match is in the submittals to get 15.5 SEER
The fan speed is set from the schematic on the blower wheel to
2 1/2 tons
Air flow is good

clawrence
07-28-2016, 06:42 PM
Sight glass bubbles than go's full
After 1min or 2

clawrence
07-28-2016, 06:45 PM
I am asking this question so to be sure I am getting the 15.5SEER
I am asking if someone has set up a unit like this. Did you set sub-cooling to condenser and add a few degrees to make sure evap is completely saturated

clawrence
07-28-2016, 06:48 PM
Being the TXV is a 3ton

beenthere
07-28-2016, 07:12 PM
First. To begin to actually get the 15.5 SEER. You need to measure the air flow, a bit more accurately, then just feeling how hard it blows out of the registers. At least check the ESP to see if your static is inline with what the air handler specs say it should be. SC doesn't mean much, if the air flow is not close to proper CFM.

Doesn't matter if the TXV is a 2.5, or 3 ton.

rsmith46
07-28-2016, 08:16 PM
Sight glass bubbles than go's full
After 1min or 2

Only means you have some subcooling.

J-P Lajoie
07-28-2016, 10:12 PM
Just take a look to the sub-cooling chart, usually located inside the electrical outdoor unit pannel. If your mesure match with the chart, you should be OK.

hogdog1
07-28-2016, 10:29 PM
forget about the sight glass you arent on that type of system. make sure your static is within range. 8 is fine. a good temp check is important as well as zerod gauges. gl

clawrence
07-29-2016, 07:54 AM
Thank you for helping