Any HVAC guys in the house ?

[Deleted User]

Been experiencing a problem with my central air conditioning for about the past week or so. There are times where I will notice that the house seems a little warm and I'll check to see if its running. The outside compressor will be running but the inside unit (air handler ??? - forgive my nomenclature) isn't blowing any air. So if I adjust the thermostat up to shut the unit off, I leave it set for a while (about an hour) then cycle it back on it comes back and everything is fine. Any suggestions ? Is something on the way out on the system ? Suggestions welcome. As always thanks in advance. :cool:

chumlie

Check your filters.

disneyjoe7

Sounds like a starter cap in the blower going bad.


Jack of all trades, master of none.

brgman

Does it need a charge?
I must have a small leak in my system that causes it to need a charge each year.It will run but not put out cool air.
After a recharge it's good til next summer.
Thats all i know about it.

Joe08867

Sounds like your low on charge. If the system is low it will accumulate ice on the condenser and that is why you have no air flow.

Get it charged and you should be good to go unless the leak is real bad.

bmbguy

Is the blower still running when thei air stops moving or not? I just had my fan quit on me a few weeks ago -- found a bad solder joint on the fan control board inside the attic unit. Reflowed the joint and it's been good ever since. If that hadn't worked, replacing that board was the next option (the fan/cap combo seemed to work fine when hooked directly to line voltage). Not that difficult to do if that turns out to be the problem.

The relay(s) on that board switch the fan on and off.

Polkie2009

How old is the system and thermostat? Are you sure the blower motor isn't running and that the evaporator coil isn't frosted up so much that it's not allowing any air to blow across the coils, thus not allowing any air to come through your interior air registers? Sometimes this problem can be as simple as a bad blower relay, a connection to it, and as bmbguy mentioned on newer units with motherboards,these joints can go bad too. How old is the thermostat??? The connections on them can go bad also over time. Hopefully this can help.

obieone

1st thing you want to do is ensure you have airflow. If no, then DO NOT run the a/c until you get airflow, you can damage the compressor, and that will get expensive.
If you DO have airflow, then you MIGHT be low on gas....
or you might have a restriction in the liquid line, like a clogged filter-drier, or the screen on the metering device, or a bad TXV, or a bad reversing valve(heat pump), or you might have a dirty evaporator, or.....or...
It could be a lot of things.
Basically, if you have airflow inside the house, and the outdoor fan and compressor are running, you'll have to call a service co.
Sorry.

gdb

X2 on the icing theory.

[Deleted User]

Thanks for the many suggestions. I am going to check the thing over as best as I can this weekend. If things persist I 'll call for service. Had the system off all day yesterday, ran it last night without a hitch. A little frustrating that the behavior isn't consistent. It would make it easier to troubleshoot. :cool:

[Deleted User]

Polkie2009 wrote: »

How old is the system and thermostat? Are you sure the blower motor isn't running and that the evaporator coil isn't frosted up so much that it's not allowing any air to blow across the coils, thus not allowing any air to come through your interior air registers? Sometimes this problem can be as simple as a bad blower relay, a connection to it, and as bmbguy mentioned on newer units with motherboards,these joints can go bad too. How old is the thermostat??? The connections on them can go bad also over time. Hopefully this can help.

The system was installed in 1995. The blower and thermostat are that old. The compressor was replaced in 2001 or 2002. :cool:

brgman

nap wrote: »

Thanks for the many suggestions. I am going to check the thing over as best as I can this weekend. If things persist I 'll call for service. Had the system off all day yesterday, ran it last night without a hitch. A little frustrating that the behavior isn't consistent. It would make it easier to troubleshoot. :cool:

Nap i think you might want to move onthis project as it will be pushin 100 startin tomorrow.
If not for you, do it for the equipment man!

codyc1ark

brgman wrote: »

Nap i think you might want to move onthis project as it will be pushin 100 startin tomorrow.
If not for you, do it for the equipment man!

I think your confused, Nap keeps his 'dwelling' at well over 100 year round. The kids say the devil lives there...

:cheesygrin:

I can speak for the frozen coil, my system was about 3 years old when it developed a pinhole in the coil, lost all fluid, and had to have a new coil and the system recharged. The coil was covered, so I got out for about 600 bones, but it DID take three days for the coil to arrive in the summer. Taking the cover off is very easy if it happens again, just look for the access points and unscrew that baby for inspection, you very well may be having an air flow issue.

[Deleted User]

brgman wrote: »

Nap i think you might want to move onthis project as it will be pushin 100 startin tomorrow.
If not for you, do it for the equipment man!

I hear ya ! Fortunately, I have a couple of window shakers as backup if need be. Maybe I should buy that Dared that is for sale and use it as a coil de-icer ? Nah, just kidding I love my Dared too much for that. :cool:

bmbguy

I think this discussion jinxed me and the board I mentioned back in post #6, because it crapped out again yesterday. Got a replacement board on the way so that I can change it out when I pull it to look at it. For now, I have the fan jury-rigged to another relay to turn on, so at least we're not dying of heatstroke.

Mr. Sharpe

brgman wrote: »

Does it need a charge?
I must have a small leak in my system that causes it to need a charge each year.It will run but not put out cool air.
After a recharge it's good til next summer.
Thats all i know about it.

the guy you are calling is jacking you to get it recharged! get the leak fixed by someone who knows what they're doing. and make sure they're certified in epa, if so then if you don't like how it's running just tell them and they have to fix it for free, if they don't, they're out of business

AudioGenics

I had a clogged condensate drain line that caused intermittent operation
there was alot of " stuff " in the PVC pipe that I used the exhaust output of my vacuum cleaner to push it thru.

something else to check in your investigation.

Now having Power outage ... no AC ... and tree limbs down everywhere !

[Deleted User]

Good point. I checked the pump and that seemed to be working fine. But I guess the possibility exists that the drain line feeding the pump may be clogged. Hmmmmm. :cool:

rpf65

Being an HVAC guy, the first thing I would check is the capacitor. If it is weak, more than 10% out of it's rated range, replace it. While checking the capacitor, look at the back of the motor. See if there is an oil port, it is usually a yellow cap, but could be silver colored. Could simply need a little oil. If you have an air handler (no gas furnace) it may be your thermostat. The thermostat controls the fan operation for most air handlers. Motors can be checked by turning the fan to on at thermostat, covering as much of compartment as possible, and using a clamp type meter.

[Deleted User]

rpf65 wrote: »

Being an HVAC guy, the first thing I would check is the capacitor. If it is weak, more than 10% out of it's rated range, replace it. While checking the capacitor, look at the back of the motor. See if there is an oil port, it is usually a yellow cap, but could be silver colored. Could simply need a little oil. If you have an air handler (no gas furnace) it may be your thermostat. The thermostat controls the fan operation for most air handlers. Motors can be checked by turning the fan to on at thermostat, covering as much of compartment as possible, and using a clamp type meter.

Thanks, will be looking at the cap next. Anything to look at speciffically on the thermostat ? It is a GE model, mechanical type that was installed at the time the system was put in (1995). Yesterday I took the cover off and cleaned it, very dusty. Is there something to check beyond this ? :cool:

obieone

I'd strongly recommend upgrading to a programmable t-stat. Specifically, a Honeywell FocusPro 6000. Prices vary between $55-80 depending on the application.
The only problem is, you'll need a minimum of 5 wires, so you can tie in the common. If not, you'll have to change the batteries.

[Deleted User]

obieone wrote: »

I'd strongly recommend upgrading to a programmable t-stat. Specifically, a Honeywell FocusPro 6000. Prices vary between $55-80 depending on the application.
The only problem is, you'll need a minimum of 5 wires, so you can tie in the common. If not, you'll have to change the batteries.

Noted - I was strongly considering a thermostat change. I'd like to understand what is causing the problem before I do that though. Cheers. :cool:

disneyjoe7

rpf65 wrote: »

Being an HVAC guy, the first thing I would check is the capacitor. If it is weak, more than 10% out of it's rated range, replace it. While checking the capacitor, look at the back of the motor. See if there is an oil port, it is usually a yellow cap, but could be silver colored. Could simply need a little oil. If you have an air handler (no gas furnace) it may be your thermostat. The thermostat controls the fan operation for most air handlers. Motors can be checked by turning the fan to on at thermostat, covering as much of compartment as possible, and using a clamp type meter.

Gee someone agreed with me on Cap Woo Hoo...

rpf65 hope you rock out some also.

rpf65

nap wrote: »

Thanks, will be looking at the cap next. Anything to look at speciffically on the thermostat ? It is a GE model, mechanical type that was installed at the time the system was put in (1995). Yesterday I took the cover off and cleaned it, very dusty. Is there something to check beyond this ? :cool:

Simplest thing to do is eliminate the thermostat. jumper the r and green terminal, and the fan should start. The r terminal is 24 volts/ g terminal is fan. If it sounds like it is struggling to start, and spins freely by hand, probably the cap. Weak caps will kill motors.

rpf65

A lot of alt-rock, but grew up on what is now called clasic. Of course brand new in my day

disneyjoe7

http://www.news-journalonline.com/breakingnews/2012/07/deltona-man-holds-air-conditioner-repairman-at-gunpoint-sheriffs-office-says.html

Making my local news....

brgman

disneyjoe7 wrote: »

http://www.news-journalonline.com/breakingnews/2012/07/deltona-man-holds-air-conditioner-repairman-at-gunpoint-sheriffs-office-says.html

Making my local news....

What kind of gun did you use?

disneyjoe7

Not me, but....

[Deleted User]

disneyjoe7 wrote: »

Gee someone agreed with me on Cap Woo Hoo...

rpf65 hope you rock out some also.

Never discounted your theory, just haven't got fully around to it yet. :cool:

obieone

disneyjoe7 wrote: »

http://www.news-journalonline.com/breakingnews/2012/07/deltona-man-holds-air-conditioner-repairman-at-gunpoint-sheriffs-office-says.html

Making my local news....

And THATS why, I don't do residential. But if I ever have to, I'm carrying. PERIOD.:loneranger:

[Deleted User]

rpf65 wrote: »

Simplest thing to do is eliminate the thermostat. jumper the r and green terminal, and the fan should start. The r terminal is 24 volts/ g terminal is fan. If it sounds like it is struggling to start, and spins freely by hand, probably the cap. Weak caps will kill motors.

Very useful info. I'll keep you posted, again many thanks. :cool: