Heat pump not cooling like it use to

[Patricio]

Our heat pump is not cooling so hot, A-coil is clean, feels cold, filters are new, changed regularly, condensor is cleaned regularly, condensor fan is running, exhaust is warm not hot. Unit is not cooling like before. Question: Does it need a freon fix? Or something else.

13 year Lenox in South Texas. Our summer is coming fast, already in the daytime 90's. Momma likes it cool.

[RegUS_PatOff]

model number ?

[jumptrout]

At that age most likely a refrigerant leak.

Pressure gauges should read 69psi on the low side.

Charge it up to get you by while shopping for a replacement unit.

WARNING: R-22 refrigerant quadrupled in price in January. A refrigerant top off will not be inexpensive.

[Bullstok]

Pressure gauges should read 69psi on the low side.

Say huh?

[jumptrout]

Say huh?

Unless it is a R-410a system,then low side would be about 125 psi.

[RegUS_PatOff]

model number ?

[jumptrout]

This temperature pressure chart will help explain.

Look for a 40 degree evaporator temperature then reference the psi for R22 or R410a.

Exact pressures are 68.6 and 118.9 respectively.

Edited May 6, 2012 by jumptrout
spell

[Bullstok]

Ok, that is a refrigeration saturation chart... So is this a txv or a piston? r22? And no checking evaporator air flow (cfm), evaporator temp drop (delta t), evaporator inlet wet bulb, condenser inlet dry bulb temp, super heat (if piston), sub cool (if txv)? At least a few of these are necessary for proper charging. Also on a heat pump there is a reversing valve that needs to be changing over correctly and not half stuck.

then there is this:

model number ?

Edited May 6, 2012 by Bullstok

[jumptrout]

I would have suggested those checks to him if he were a technician and not a home owner and probably without gauges as well.

But then,if he was a technician he probably would not be seeking help on a DIY forum.

[jumptrout]

P.S. Carrier introduced R410a equipment in 1996. No other company used it until 2000.

[Bullstok]

No offense - just suggesting it's complicated. I get people that suggest all sorts of ways to "charge" systems when I'm at work. The only way a homeowner is going to do anything is by temps anyhow. If the evap is freezing up or such. FWIW: I would guess if it is running correctly on a 90 deg ambient temp day, it would be around 95 to 105 low side and 215 to 225 high side.

Anyhow, if it is not very humid, most any air source split a/c should be giving a 20 degree drop to the air temperature in the house. The more humid it is, the less temp difference you will see. If it snot in that range it might be leaking refrigerant. If the indoor coil is freezing or you see ice on the large line outside the house, you got trouble. Start looking for oil residue on the service ports and such- mainly any fittings on the lines that are threaded together (indoor next to the coil there is usually a fitting or two as well). These are your first bet if you are gonna fix anything without proper equipment. Usually if there is a refrigerant leak there is a oil leak. Get out your dawn dishsoap (or buy some big blu - i'm not getting into that discussion again ) and start smearing it on and looking for bubbles.

Edited May 6, 2012 by Bullstok

[jumptrout]

No offense taken Bullstok ikko ikki. It is that since I have been in this business 15 years before you were born grasshopper,I was trying to give Patricio something he might work with.

I will humbly bow out now from this inquiry.

[Patricio]

Thanks for everybody's help. No I am not an Heat Pump Tech, just a lowly appliance repairman. I don't have the gauges, but I understand cooling & heating theory Unit is not freezing up & is cooling, just not like it did last fall. I have helped AC techs in the past. I figured I had a leak in the system. I have a oil section between to sweat-ed joints one & half foot apart just outside the unit on the uninsulated small line. Did not think to soap the line, but that makes since, that's how I check LP & Natural gas lines for gas appliances. Have a tech coming on Monday. Just wanted to be up on his service call. Will post a model Number on next post.

Unit is well maintained and is comfortable now, but temps are not falling below 78 inside. Probably needs to be topped off. I do Have a capacitor on the blowing Unit that is rusted beyond recognition (South Texas Coastal Bend humidity everything tries to rust) but it is energizing the fan just fine.

[Bullstok]

I have been in this business 15 years before you were born

Sweet, how were the systems with R1a? Hand crank air conditioning would be a pain in the ass.

Edited May 6, 2012 by Bullstok

[Patricio]

Lenox model # HP26-036-7P serial # 5801C 46984 HCFC - 22 Factory charge 9 pds - 8 ozs Design Pressure 278 psig - High ... 144 psig - Low

All lines to outside unit solder connections Evaporator & insulated line cool not cold. No icing. Unit cycles fine Just not cold only cool.

[kdog]

Hand crank air conditioning would be a pain in the ass.

We had Gilligan back then ...........

[Bullstok]

I figured I had a leak in the system. I have a oil section between to sweat-ed joints one & half foot apart just outside the unit on the uninsulated small line.

Make sure the condenser has not settled recently for some reason. Or been knocked around by someones riding lawn mower If it is sinking (being washed out from underneath or some such thing) you could end up doing this all over again later. You don't want the pipes holding up one side of the unit. Eees bad for them.

Edited May 7, 2012 by Bullstok

[RegUS_PatOff]

We had Gilligan back then ...........

if she would have played her cards right,

it could have been "Mary Ann's Island"

[Patricio]

OK I was correct, Freon leak at soldered joint. To Weld over leak & replace 3 pounds of freon $800 does that sound reasonable? This is an established company, they installed the system 13 years ago. Input please.

[Bullstok]

My input: thirteen years ago they did some sh@&?y brazing (unless it really is regular solder, I ran into that once. Not very smart.) Other than that, I don't get involved in price wars.

Edited May 8, 2012 by Bullstok

[Patricio]

No price War just a honest opinion. Brazing is not hard, I have done a lot of it. The cost of Brazing a splice, putting 3 pounds of Freon into system, confirming correct pressure, & checking the capacitors to see if they are getting weak for $800. Is AC work that expensive cause of the price of Freon? Should I go To our Trade School & for AC repair & take up a new profession (everybody has AC in South Texas, job security) Is $800 reasonable or way off. That is my Question.

[Bullstok]

I dont mean it like that. What other people charge is none of my business. I do not tell customers that the competition is wrong. I give my honest opinion after doing a proper diagnosis and let them decide. At face value that price sounds high. But there are 50 million variables that I don't know that could be leading to that price. Unless I have seen it myself, I like to keep my feet out of my mouth. You could live in the center of the desert for all I know. Out in real life, I prefer to sell by not selling. There are plenty others willing to go on and on about how great their cheeseburger is.

Anyhow... So let's say that what you said was my proper diagnosis:

Pull remaining freon into condenser. Purge system with nitrogen. Braze leaking joint(s). Pressurize with nitrogen (or skip). Vac system down. Confirm no more leaks. Release condenser charge. Run system. Charge properly (verify air flow and such). Check electrical, capacitor, amp draw on all 3 motors, etc.

Guessing 3 to 4 hours or so labor depending on exactlly how bad it is. Let's say $150 to 200.

Guessing $200 to 300 material depending on how low on freon. Braze rod, acetylene, nitrogen, misc.

Service call fee (varies by company) say $70

So around $500 assuming no other issues.

Oh wait... $300 union fee. Just kidding, please no cement shoes for me. Thx.

Edited May 8, 2012 by Bullstok

[Daveb1972]

Leaks are often just not worth fixing here in NY. with the average life expectancy of a condenser at 10-15 years, (the engineers tell us 10 years) your unit is already well within that range. I'd get a replacement quote first (2-3 of them in fact) and see if you can slip into something a little more efficient. That said, a propper repair can get you a few more good years.

BUT BEWARE, money inversted in this repair can be wasted if next year the comp goes, or another leak is found....etc. Also some companies will tell you they can change the condensing unit and reuse the evaporator, I'd be reall leery of that as well. The new systems are allmost all R410a which has much higher pressure durring operation, and the coils are matched to the condensor, so to get correct cooling and efficiency, they need to be correctly matched. The line set can sometimes be reused, if all of the connections are brazed (due to the higher pressures).

Some techs use "hard solder" or "Stay Brite 8" solder, which is supposed to be stronger than standard solder, but I prefer braze, make sure he purges with N2 and verifies fix with an actual vaccume (micron)guage (the manifold set gauge doesnt count!) I've seen vereren techs use the sound of the vaccume pump to determine if the system is propperly evacuated.Some times they will reccomend fixed metering instead of TXV, dont do it!

The pricing sounds about right for that type of repair, but I'd wanna be sure all of the leaks have been found. What did the Tech use to find the leak? was the evap checked as well? Chances are all of the joints in this system are soldered, and may exibit the same issue soon too.

When shopping for a quote, look for the major players; Carrier/Bryant, Lennox, Trane. I'd skip the Goodmans, Kenmore, Tappan, Kelvinator, etc....but thats my prefference.

[Shootist]

If you have an obvious freon leak on an exterior solder joint it would be foolish NOT to fix it. $800 is overpriced. Call around and you may get it as low as $300 if you get a cash discount. You're talking 30-45 minutes worth of work. I'm kind of curious how they we're able to determine exactly how much freon that was going to be added.

Once the leak is fixed it doesn't matter the cost of R-22 as you wont need any.....for a while.