Home Air Conditioning Repair/Replacement Question

[Mule3006Elk]

Totally not hunting related but I know there are some smart guys/gals on this forum.

My air conditioner took a dive. Coil leaking inside garage at the furnace.
A/C is 10 years old.

Does it make since to replace the coil only or the entire system?

They, repair shop, recommend replacing the furnace at the same. Furnace as far as I'm aware is working fine.
I don't want to waste money or get scammed.

Question is: coil only, coil and AC unit as a system which seems to make since, OR entire AC system + furnace?

 

[ElkNut1]

That's not a very old unit. Water or refrigerant leaking? Is this a heat pump?

ElkNut

 

[rickjames80]

I agree, if it's only 10 years old I would just fix the issue. Not replace the whole thing. I vote for coil only.

 

[Mule3006Elk]

They did a nitrogen pressure test and identified a leak and recommended replacing the downstairs evaporator coil. He did a bubble test and didn't identify any bubbles on the exposed coil but the nitrogen sensor (went off) in the right lower quadrant of the evaporator coil every time he went in that area. I was watching him the entire time. Pressure went from 330 PSI to 310 PSI in less than an hour. So there is a leak. No definite leak on the AC unit itself (outside) but obviously not excluded.

I am getting a 2nd opinion tomorrow.

Sounds like from the replies so far if the furnace is fine just leave it. I know it's less to replace since it has to be pulled anyway to change the evaporator coil. $2800 for furnace if I do it all at the same time.

 

[GSPHUNTER]

You have to understand life expectancy is 15 years +-. So, how long are you staying put? if some time, I would replace furnace and coil. I work in A/C for 38 .years and I found once a coil springs a leak, it's likely to leak again, metal fatigue, vibration and such. Not always the case but likely. Go with at least 90% furnace. As for the condensing unit, out side unit, Thats your call. Depending on where you live, say the desert, it might be a good idea. High temp. and dry air is hard on outside unit. That being said, cost is always a consideration but, it's no going to be cheaper in 5 years.

 

[Mule3006Elk]

That's not a very old unit. Water or refrigerant leaking? Is this a heat pump?

ElkNut

Downstairs evaporator coil. Grr

 

[GSPHUNTER]

Locating small leaks can be a bitch. 330 to 310 in less than an hour is a fairly small leak. If that were in ten minutes that's another thing. If I suspected a leak in a certain area I would soap suds it and check that area several minutes later. It some times takes that long for a bubble spot to build up. If he suspect leak is in evaporator he can cap off both liquid and suction line at coil tail peace and pressure test just that.

 

[Mule3006Elk]

Locating small leaks can be a bitch. 330 to 310 in less than an hour is a fairly small leak. If that were in ten minutes that's another thing. If I suspected a leak in a certain area I would soap suds it and check that area several minutes later. It some times takes that long for a bubble spot to build up. If he suspect leak is in evaporator he can cap off both liquid and suction line at coil tail peace and pressure test just that.

Thank you for your input. I love this site.
That is absolutely out of my wheelhouse.

I'm a deer in headlights and taking them at face value.
He's not pushy at all and I believe he identified the leak.
Unclear if should replace the entire system (inside/outside). Cost savings in a few years?
If I replace the coil and it last 5-10 years then good call. If the outside unit dives I'll wish I had just replace the system. It's a judgment call of course.
As you know, it cheaper to do it all at once vs. replacing the evaporator coil and outside condenser separately.

 

[GSPHUNTER]

Keep in mind, Trouble shooting a A/C system from miles away on a forum, is far different than hands on. But you already know that.

 

[Mule3006Elk]

Keep in mind, Trouble shooting a A/C system from miles away on a forum, is far different than hands on. But you already know that.

Absolutely Agree.

Is it recommended to replace the evaporator coil (which is bad) along with the outside condenser as one system? This is what they recommended. Few thousand difference in price vs. evaporator coil only. If this is the general recommendation, within the industry, I am fine with that. I don't want to replace the outside condenser, just because the evaporator coil is bad, if it's not necessary or not standard practice within the industry.

I do have a 2nd opinion scheduled for tomorrow which is never a bad idea.

 

[GSPHUNTER]

If you have no reason to believe there is no issue with outside unit then go with your gut. Tech. should be able to preform a standard service check and give you his best opinion based on his findings. Are amp readings well within normal ranges and is discharge pressure normal. That one could be resolved with a good coil cleaning. What ever he does make sure he replaces liquid line drier. Most tech. put drier near outside unit but remember the purpose of the drier is to protect the expansion device from and small particles and moisture which may be in system. I always install them just before evaporate.

 

[JoeDirt]

How old is the furnace? 10 years also?

 

[Mule3006Elk]

How old is the furnace? 10 years also?

Yes

 

[260madman]

Mine just blew refrigerant an hour ago when I went out on the patio to the grill. Big white cloud. This one is going to hurt. 90 degrees right now too so off to Walmart for a window unit to get us through until a someone can get to the house hopefully in a week. Supposed to be 90 for a week also. Should be fun.

 

[GSPHUNTER]

Mine just blew refrigerant an hour ago when I went out on the patio to the grill. Big white cloud. This one is going to hurt. 90 degrees right now too so off to Walmart for a window unit to get us through until a someone can get to the house hopefully in a week. Supposed to be 90 for a week also. Should be fun.

That white cloud was a mix of oil and refrigerant.. Let the A/C tech. know about it when he comes to fix it. Prolly didn't lose enough oil to matter but, one never knows.

 

[GSPHUNTER]

That white cloud was a mix of oil and refrigerant.. Let the A/C tech. know about it when he comes to fix it. Prolly didn't lose enough oil to matter but, one never knows.

My sister live in So. Wisconsin. 92 there today but the humidity was only 18%.

 

[Mule3006Elk]

Mine just blew refrigerant an hour ago when I went out on the patio to the grill. Big white cloud. This one is going to hurt. 90 degrees right now too so off to Walmart for a window unit to get us through until a someone can get to the house hopefully in a week. Supposed to be 90 for a week also. Should be fun.

Sorry to hear that. I feel your pain!

 

[DenverCountryBoy]

How well has the furnace been maintained? Does it get yearly maintenance and monthly filter changes or was this the first time it has been opened in the last decade?

 

[Mule3006Elk]

Just had a 2nd opinion.
Very interesting.
Once it's all said and done I will provide an update.

 

[GSPHUNTER]

Just had a 2nd opinion.
Very interesting.
Once it's all said and done I will provide an update.

Please do. the very interesting comment has me wondering.