a/c not turning on

Reply

  #1  
Old 06-30-18, 11:24 AM
Member
Thread Starter
Join Date: Aug 2016
Posts: 51
a/c not turning on

this is a rental unit and occupants trashed the place, I suspect the ac has been out for many months

nothing happens when i turn on the ac at the thermostat, no noise, nothing
doesn't trip the breaker or anything (i reset the breaker also)

not sure what steps to take first, i just gathered a bunch of pictures for now

the ac was purchased new at the end of 2010/ start of 2011

https://drive.google.com/open?id=1fH...3ID2vkaoGmRcWt
https://drive.google.com/open?id=1Xf...lG1z19OUVHhs3s
https://drive.google.com/open?id=1jA..._kAA5Z_08EbyQK
https://drive.google.com/open?id=1_E...QUQv4CuQJ8Pmb2
https://drive.google.com/open?id=1NA...wR23h99qATWjid
 
Sponsored Links
  #2  
Old 06-30-18, 11:44 AM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,225
Is the low voltage wire even connected to this unit?
 
  #3  
Old 06-30-18, 02:50 PM
Member
Thread Starter
Join Date: Aug 2016
Posts: 51
I don't even know what a low voltage wire is, I will probably just get a HVAC person to come and check it out.
 
  #4  
Old 06-30-18, 06:31 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,225
I believe it shown in AC4 JPEG.
 
  #5  
Old 06-30-18, 07:31 PM
Member
Join Date: Oct 2016
Posts: 652
I see an aftermarket high pressure cutout control that’s been bypassed, but the other pictures don’t show anything.
You’ll need some tools and a meter to troubleshoot. Do you have those things?
I don’t see a control wire going into the unit either.
 
  #6  
Old 06-30-18, 09:36 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,225


The yellow arrow is pointing to the most likely location of your control wire.

It usually looks more like this but your wire is in a plastic conduit...




It will usually connect to the condenser with a couple of orange wire nuts...


Turn off the thermostat before trying to reconnect the 2 wires or you might pop a fuse in the indoor unit. Usually 3 amp for gas furnaces and 5 amp for air handlers.

 
  #7  
Old 07-02-18, 10:22 AM
Member
Thread Starter
Join Date: Aug 2016
Posts: 51
Here is a pic of the run capacity and the control wire?

https://drive.google.com/file/d/15_9...w?usp=drivesdk
Name:  acbox.jpg
Views: 56
Size:  79.7 KB
 

Last edited by PJmax; 07-02-18 at 11:13 AM. Reason: added labeled pic from link
  #8  
Old 07-02-18, 11:16 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: NJ - USA
Posts: 43,771
The two connections I circled in red are the 24vac that activates the contactor. As mentioned.... I don't see any protection devices, like hi/lo pressure switches, connected.

I also only see one single capacitor. Is there a second one elsewhere on that unit ?
The connection I circled in white looks to be a connection that would normally be on a capacitor.

You may be in need of some "hands-on" professional help there.
 
  #9  
Old 07-02-18, 06:50 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,225
Looks like a dual cap on my ipad. Red is Com, Yellow is Hem and brown is fan.

I have seen some serious issues when the low voltage wire is run in the same whip as the high voltage wire.

Water got inside of the whip and shorted the high voltage with the low voltage.
I had to replace the contactor, the thermostat and the furnace control board.

I hope this is a very different issue.
 
  #10  
Old 07-03-18, 01:40 PM
Member
Thread Starter
Join Date: Aug 2016
Posts: 51
had the HVAC tech come and check it out. he got the unit running from inside the garage but could not get it working from the main thermostat.

the previous tenant was running something very illegal, there were new vents in the garage, and wiring that led to what most likely used to be an alternative thermostat

hvac tech seemed really honest and stated that the whole unit would need to be replaced because:

1. it was very old, likely from 1986 when the house was built, the flue (vent?) inside the garage needed to be replaced and they don't make them anymore. he said it would be dangerous to operate, in case there was a leak, the house would intake carbon monoxide (dioxide?)

2. the evaporator coil is corroded.

3. the condenser is almost 8 years old and uses R-22 refrigerant while may not be a problem now, won't be available to use in the near future.

he also stated that other a/c companies may offer to fix it, but he couldn't do it because he wouldn't be able to sleep at night.

it is mounted to the garage's ceiling, not a freestanding ac/heating system.

any thoughts? do i just trust this guy or get a 2nd opinion?

there was no charge for the service call, and he was out there for around an hour.
 
  #11  
Old 07-03-18, 03:56 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: NJ - USA
Posts: 43,771
Looks the furnace was from 1986 but the A/C was either replaced or installed at a later date if it was only 8 years old.

Condenser 8 years old and R-22 are not issues.
A corroded evaporator, and I guess leaking, is a problem.

Should you trust the guy...... probably but you should get a second estimate to replace existing equipment.
 
  #12  
Old 07-03-18, 04:24 PM
Member
Join Date: Oct 2016
Posts: 652
So what did he find was keeping the unit from running?
 
  #13  
Old 07-03-18, 04:34 PM
Member
Thread Starter
Join Date: Aug 2016
Posts: 51
I think it was just the thermostat not wired up to the house

But yeah, I will get another estimate. If they can fix it and it's safe, I will go that route.

I think he manually turned it on using the wiring from the thermostat that used to be in the garage
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'