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Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 8675
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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We have an old york ducted reverse cycle air conditioner.

Customer Question

Hi,
we have an old york ducted reverse cycle air conditioner.
When on cooling, only the inside fan works, nothing happens with the out door unit.
When on heating, everything works fine.
Its hard to read the model number but I think that it is one of the following:
E102024A78A
E103024A78A
E10B024A78A
Can you please tell me what is wrong, where to get parts etc
Thanks
Submitted: 1 year ago.
Category: HVAC
Expert:  Phil replied 1 year ago.

Hello,

Some trouble shooting will be required.

Please attach a well focused, close up photo of the wiring diagram glued inside of the blower service panel,you can use the paper clipicon at the right end of the toolbar at the top of this dialog box,Include a picture of the thermostat wire connections to the printed circuit board in the same area.

If there is no paper clip icon, look for the '+attach files' link at left of your send button.

I can mark it up with trouble shooting instructions. You will need a multi meter ($30 at a hardware store) and some experience working with appliances, let me know a lot about your skill sets in those regards.

We can go from there.

Customer: replied 1 year ago.
Hi,
I have attached the only wiring diagram that was in the lid of the "control box" in the out door unit.
There is nothing in the unit up in the roof.(no diagram or circuit boards)
I have a multi meter but am not sure exactly how it works other than to test if there is power or not, I dont understand the other functions.
Expert:  Phil replied 1 year ago.

Thanks for the well focused diagram, it is exactly what I needed.

http://screencast.com/t/YFSfPCon93b

Use the multi meter to see if you get a high voltage read across the two wires at the disconnect switch on the outside unit. It is mounted on the unit, or on the wall next to the unit.

If you have power there look for the high pressure safety cut out switch..it is mounted inside the unit, in the electrical controls box... and sometimes you have to remove the sheet metal cover over the area where the power wires enter to unit to get to it.

Most times however there is a 1 inch diameter hole punched into the cabinet of the unit, with the reset button hidden about a half inch inside the hole. Press that button.

If you have the thermostat set on cooling, and it starts, then that was the problem. If you hear just the compressor starting, but the fan on top does not start, then the fan motor needs to be replaced most likely.

If the entire unit starts, including the fan turn the system off at the disconnect switch, then use a hose pressed against the finned condenser coil and blast all of the dirt out from between the fins, make sure you do not get fan motor inside wet.

When it dries out, turn the power on again to the unit, It should be OK for the day.

Then go shopping and buy 3 cans of foaming air conditioner condenser coil cleaner kit... and use it to clean the coil.

Thanks for letting me work with you. When we are finished, if my answer has been polite, professional,and thorough, please click one of the ratings . If you still need help let me know!. Expert is not paid for assisting you until you rate answer. Feel free to follow up for30 days at no additional cost.

We can go from here as necessary.

Customer: replied 1 year ago.
There is power at the switch but I can't find a reset button.
I have attached 3 more photos that will hopefully help.
Just to clarify, you do know that the heating works, it's just the cooling that doesn't?
Expert:  Phil replied 1 year ago.

Hello again

http://screencast.com/t/ClWESbf3pN

Yes I know that it is only the cooling that does not work, however heating can seem to work if the booster heat is on but the heat pump is not running.

Tell me please if the heat pump, outside runs in heating mode, with the fan on top running as well as the compressor. If it does, then I am barking up the wrong tree with the high pressure cut out switch etc.

Next lets do the following tests.

http://screencast.com/t/fP33I6kVPugu

Customer: replied 1 year ago.
in heating mode the compressor and fan on top are both working.
Expert:  Phil replied 1 year ago.

Thanks,

http://screencast.com/t/fP33I6kVPugu

Do the tests described at the hyperlink above.

I posted it earlier, if you are doing this with a cell phone you might not have scrolled down enough to see it.

Let me know about that... we can go from there.

Customer: replied 1 year ago.
Hi,
No reading for anything heating or cooling.
I have tested the multi meter and it is working.
Expert:  Phil replied 1 year ago.

Hello again, sorry I am late, there was somewhat of a medical emergency.

You are getting no 24volts to the thermostat from the indoor unit.. It is either a blown fuse in the 24volt circuit in the indoor unit, a bad transformer, or the furnace not plugged or switched off...98%

chance one of those is the cultrit.. 2% chance that the thermostat is bad.

Please attach a well focused, close up photo of the wiring diagram glued inside the service panel,you can use the paper clip icon at the right end of the toolbar at the top of this dialog box,Include a picture of the thermostat wire connections to the printed circuit board in the same area.

If there is no paper clip-icon, look for the '+attach files' link at left of your send button.

I can mark it up with trouble shooting instructions.

Customer: replied 1 year ago.
I checked the fuse in the screw in thing in the bottom of the box & it is ok.
Expert:  Phil replied 1 year ago.

Hello again,

http://screencast.com/t/hRKYo1Sfjk

It is starting to look like the thermostat is not connecting R, or Y or X to the terminal strip when set in cooling mode. Those tests will tell me a lot about that.

Customer: replied 1 year ago.
Hi,
R-x no reading
R-b approx 23v
X-y no reading
X-g approx 20v
Expert:  Phil replied 1 year ago.

Thanks for the tests, here are more.

http://screencast.com/t/5qADLF4crlMS

Customer: replied 1 year ago.
B-O on both strips 23v approx
B-Y & B-X on both strips no reading
Expert:  Phil replied 1 year ago.

Thanks, ***** ***** jumper out of a paper clip wire and use it to jumper B to Y.. where the thermostat wires land in the air handler... tell me if outside unit comes on or not.

http://screencast.com/t/sB7jz6gkKx

If the outside unit runs, when B to Y are jumpered, then the thermostat is almost certainly bad.

Customer: replied 1 year ago.
Still nothing on outside unit.
Customer: replied 1 year ago.
What do we do next ?
Expert:  Phil replied 1 year ago.

Move the Y terminal on the thermostat to the B terminal as a test only (so that you have two wires on B)

Then go to the outside unit where there thermostat wires connect inside the unit, and measure voltage across all 3 combinations of the 3 wires and tell me which wires if any read 24 volts.

Next locate the contactor (big relay) that sends power to the compressor, locate the 24 volt coil terminals on it, and tell me if you you get 24v across those two terminals or not.

We can go from there.

Customer: replied 1 year ago.
Does the jumper still need to be in place for the next steps?
Expert:  Phil replied 1 year ago.

Yes

Customer: replied 1 year ago.
Hi,
Sorry for the late reply, been flat out at work.
Not sure about what wires are what on the thermostat.
See attached photos.
Expert:  Phil replied 1 year ago.

Hello again,

http://screencast.com/t/IItlMMv4vto

We can go from there

Customer: replied 1 year ago.
Sorry, I thought you could use the one I send before.
Expert:  Phil replied 1 year ago.

Thanks, ***** ***** a great photo... I enlarged it and marked it up for you, but the internet is slow just now it seems so its not downloading very fast.

Set the thermostat for cooling and down to 60F. Follow the thermostat wires to the unit, There are 6 terminals R, B, Y, O, W and X

tell me if you get a 24 volt read between R and B or not If you do get 24v there fit a jumper between R and W, tell me what happens.

Then fit a jumper between R and Y and tell me what happens.

................

If you get results at the terminal strip, repeat these jumper tests at the thermostat terminal strip.

We can go from there

Customer: replied 1 year ago.
i will try this when i get home tonight.
Still no photo, didnt it upload?
Are you in America?
Expert:  Phil replied 1 year ago.

Hello again, your photo uploaded just fine, the service I use to send my mark ups is having problems apparently. I just checked again, its still down.

I am an american currently traveling in central america, the wi fi here is as good as in the US, better in many cases because of the lack of hard wire phones here in the country side. The problem is with the 'Snagit' server in Canada I believe.

Are you having trouble with my verbal instructions? I can elaborate if needed.

Customer: replied 1 year ago.
I'm a bit confused, are we doing something different now or are we still trying to do the same thing or have you given me extra steps ???????
Expert:  Phil replied 1 year ago.

Hello again, no extra steps. Just do the voltage and jumper tests on the thermostat terminal strip shown in the lower left section of the wiring diagram that I described earlier.

Here is a copy of my previous post on that issue:

"Set the thermostat for cooling and down to 60F. Follow the thermostat wires to the unit, There are 6 terminals R, B, Y, O, W and X

tell me if you get a 24 volt read between R and B or not If you do get 24v there fit a jumper between R and W, tell me what happens.

Then fit a jumper between R and Y and tell me what happens.

................

If you get results at the terminal strip, repeat these jumper tests at the thermostat terminal strip."

Let me know how that goes, or if you have any questions about doing those tests.

Customer: replied 1 year ago.
just to clarify,
You want this:
"set the thermostat for cooling and down to 60F. Follow the thermostat wires to the unit, There are 6 terminals R, B, Y, O, W and X
tell me if you get a 24 volt read between R and B or not If you do get 24v there fit a jumper between R and W, tell me what happens.
Then fit a jumper between R and Y and tell me what happens.
If you get results at the terminal strip, repeat these jumper tests at the thermostat terminal strip."You want this done with the jumper in place B-Y in the unit in the roof (indoor unit)
When you say "Follow the thermostat wires to the unit," I assume that you mean the unit in the roof (indoor unit) is that correct?INSTEAD OF THIS:
Move the Y terminal on the thermostat to the B terminal as a test only (so that you have two wires on B)
Then go to the outside unit where there thermostat wires connect inside the unit, and measure voltage across all 3 combinations of the 3 wires and tell me which wires if any read 24 volts.
Next locate the contactor (big relay) that sends power to the compressor, locate the 24 volt coil terminals on it, and tell me if you you get 24v across those two terminals or not.
Expert:  Phil replied 1 year ago.

Hello again.

I am sorry, you had not reported any results from the first set of instructions I gave, so I mistakenly went forward with this last set of instructions.

Here are those instructions again. Tell me what results you get, we can go from there.

Move the Y terminal on the thermostat to the B terminal as a test only (so that you have two wires on B)

Then go to the outside unit where there thermostat wires connect inside the unit, and measure voltage across all 3 combinations of the 3 wires and tell me which wires if any read 24 volts.

Next locate the contactor (big relay) that sends power to the compressor, locate the 24 volt coil terminals on it, and tell me if you you get 24v across those two terminals or not.

INSTEAD OF THIS:Move the Y terminal on the thermostat to the B terminal as a test only (so that you have two wires on B)Then go to the outside unit where there thermostat wires connect inside the unit, and measure voltage across all 3 combinations of the 3 wires and tell me which wires if any read 24 volts.Next locate the contactor (big relay) that sends power to the compressor, locate the 24 volt coil terminals on it, and tell me if you you get 24v across those two terminals or not."

Lets just stick with the results from those tests first, before we move on to my second set of instructions.

Customer: replied 1 year ago.
again, I'm not sure what wires are what on the thermostat.
I thinki t must have been changed/replaced at some point
See attached
Expert:  Phil replied 1 year ago.
Customer: replied 1 year ago.
Is there anything else we can do?
Expert:  Phil replied 1 year ago.

Hello again, given this messed up nature of the wiring and this non standard thermostat that is apparently in place, there is not much that can be done in any sort of reasonable time frame from here.

I will opt out for you, and we can see if anyone else here will take a shot at the problem.

Customer: replied 1 year ago.
Ok, thanks.
Enjoy your travels.
Customer: replied 1 year ago.
Hi,
I've managed to figure out the wires and markings at the thermostat.
Now what do I do?