It's hot in my house. No wait, it's cool now. No wait...

[Thomas]

Our AC system is on the fritz and I am hoping someone can tell me if we need a new one. We live in Florida and with a newborn, we would like control of the temperature in the house.

We have an outdoor AC unit and an indoor blower unit. The indoor blower is for the AC as well as the Heater. Within the past year, I have replaced the fan motor and the capacitor (?) both on the outside unit.

It was a little warm in the house this afternoon and the AC/blower did not seem to want to shut off. So I went out and removed the panel on the outdoor AC unit. All the wires were still wires and the capacitor was right where I left it. I replaced the panel and turned the unit back on. The fan on the outdoor unit was blowing hot air (that's good), the non-insulated pipe was hot and the insulated pipe was cold (that's good, too). When I got back inside, there was cool air coming from the vents. The unit still doesn't want to shut off and it never really gets to the temperature setting on the thermostat.

It seems like this happens frequently, I just don't go out and check it everytime.

We would very much like an AC system that cooled the house reliably. Is this something you can help me fix or do I need to call someone to the house and pay the price$$.

[roger g]

It sounds like everything "appears" to be working. Make sure that the filter is always kept clean. Sometimes a lot of dirt gets passed the filter and clogs the underside of the evaporator (the cold thing inside the furnace). You might have to clen that. Though if the coil was dirty you would probably see frost on the cold pipe as it leaves the furnace..
For a quick test, take a temperature of the room then take the temperature of the cold air coming out of your ductwork. If everything is working pretty good you should be about 20 degrees cooler coming out of the vent. So if yoour room temp is 90F then hopefully the cold air should be 70F. If the room temp is 80F then the cold air should be 60F. A 20 degree difference is pretty good.



roger

[rabadger]

Please answer the following questions

1. At what temp did you have the thermostat set on.
2. What was the temp outside.
3. What was the temp inside.
4. Are the filters clean.
5. What large town are you close to in Florida
6. What town do you live in.
7. How did it work last year.


I need questions 5 nad 6 answered to look up the design temp for cooling.

[Thomas]

1. At what temp did you have the thermostat set on.
75F

2. What was the temp outside.
>90F

3. What was the temp inside.
~85F

4. Are the filters clean.
Yes.

5. What large town are you close to in Florida
We live in Pensacola

6. What town do you live in.
Pensacola

7. How did it work last year.
About the same.

If we set the T stat lower, the unit seems to run forever and it never really gets any cooler. The power bill just goes up!

I have not checked the temp of the room versus vent air but will do that soon.

Thanks for the input. And if it comes down to needing a service for it, what is the best way to choose a contractor?

Thomas

[rabadger]

You have a outdoor design temp of 92 degrees. This means that the unit should be running a lot. At 92 degrees the unit should be running almost all day and keep the indoor temp at 72. Thats your 20 degree difference between outdoor and indoor temperatures.

As roger g stated you should be getting an approx 20 degree temp difference between the return air temp in the home and the supply air temp out of the closest register to the unit. You need to perform a couple more quick checks. You can call me if you like. 219-548-7270.

It sounds like you will be needing service.

[roger g]

Dang! I get lucky sometimes, most of the times I just wing it.:)



roger

[giddonah]

Dang! I get lucky sometimes, most of the times I just wing it.:)

Have you seen "Gross Anatomy"?

Dr. Woodruff: Are you guessing?
Joe Slovak: Am I right?
Woodruff: Yes
Slovak: Then I'm not guessing.

[roger g]

clap, clap, clap, very good.


roger

[Thomas]

Okay...The air coming out of the vents is definitely cold! The air filter is clean. I replaced the old mercury switch T-stat with a digital one this past weekend. The outside unit works as described earlier.

It feels nice in the house (78F humidity 55 - 60%). The problem is that the unit turns off before reaching the set temp, stays off for < 1 minute and kicks on again. I dont think this is good for the A/C.

I am puzzled. It feels great in the house, but in order to stop the A/C from going on and off, we have to control it manually. I was hoping a new T-stat would fix this.

Any ideas or is it time to call someone?

Thanks again,
Thomas

[rabadger]

How often does it cycle lile that? Off for a minute than on again. Sounds like a safety device is opening then has a auto reset. If a service tech comes out it will have to cycle like that when he is on site. Or you could get lucky and he will be able to figure it out by taking pressure and temperature, and electrical readings. 55-60 persent humidity seams high. you should be able to get 50% humidity if the unit is sized correctly. But it has to stay on to reach that level.

[Thomas]

After a phone conversation with Richard and a visit from a local service tech, the unit did work for another couple of weeks. The service tech replaced a capacitor (not the one I put in) and gave me a few tips on maintenance. The consensus is that we will be needing a new unit; there is a refrigerant leak, the coils have probably never been cleaned and the unit is ~15 years old.

I know a lot of people who have purchased a Heat Pump and swear by them. However, my father-in-law, whose opinion I highly respect, doesn't like them as much. I know that in the extreme cold (<25F) they do not work as well as a furnance, and to counter this, a back-up furnance is often purchased as well. Considering we live in Pensacola, FL, can you give me your input of Heat Pumps versus "normal" HVAC systems?

Also, I am having a local company as well as SEARS give me estimates on full system replacements. Any suggestions on makes, brands, etc?

This site is great for the 'break-it-yourselfers' like me!

Thomas