[hardwired]

I need to replace my 3ton Coleman twin Speed bristol that died at the end of the season last year. This unit covers 1900 sq ft upper level where the kitchen, living space and bedrooms are. Currently two zones are split 1200 sqft and 700sq ft (above garage). Load calc was 3.5Ton but contractor went with the 3Ton Coleman as no 3.5ton 2-stage at the time. Boston area.

The Air Handler is an ADP variable speed located in the attic and the coil had a TXV with a system design SEER of 12.5-13. The performance in summer hot days in upper 80's during the day could not keep it near 70F(upper 70's). We run the AC from May thru October to keep the pollen out with asthma and allergies. The two stage seemed to make sense for May/June, Sept/Oct.

As I understand the coil will need to also be replaced in the ADP along with the new outside condenser. Installer said can use an ADP coil to match or swap with one from condenser manufacturer - any opinions on which would be better?

I am also thinking to add a solar powered attic fan to reduce the attic temps in the summer. Ducts are insulated and Air Handler is factory insulated inside the cabinet.

Should I go with a 4-ton 2-stage or just go with a 3.5 ton single? Looking at 16SEER units. Nervous that another 3ton 2-stage will not be enough to handle the mid-summer load.
There seems to be some debate about whether the two stage will save you much. My electric rate is 18.5cents/KWhr.

How many amps can I expect the Copeland 2-stage scroll to pull in Hi/Low for a 4ton unit vs the single speed Copeland for 3.5ton?

 

[ID10T]

Coming from a good ole boy from Louisiana with high temps and high humidity. Both of my calculations, without doing a manual j has a range from 3.8 to 4.75 tons. Looking at the information you wrote, and my data, you should have a 4-ton system. Always make attic ventilation a priorty when your duct work is up there. You must have adequate eave venting too.

 

[hardwired]

Id,

Is that 3.8 to 4.75 ton estimate for Boston or Lousiana?

 

[ID10T]

Id,

Is that 3.8 to 4.75 ton estimate for Boston or Lousiana?

LOL, man you are waaaay up there! I actually have family in Rhode Island and in Connecticut! The 3.8 tons would be you, its a tad over 3 1/2 tons. The difference between tonnages are 12,000 btu's and 400 cfm's of air. If upgrading to a 16 seer, and its a variable speed blower motor, I would go with the 3 1/2 ton personally!

 

[George2]

I need to replace my 3ton Coleman twin Speed bristol that died at the end of the season last year. This unit covers 1900 sq ft upper level where the kitchen, living space and bedrooms are. Currently two zones are split 1200 sqft and 700sq ft (above garage). Load calc was 3.5Ton but contractor went with the 3Ton Coleman as no 3.5ton 2-stage at the time. Boston area.

The Air Handler is an ADP variable speed located in the attic and the coil had a TXV with a system design SEER of 12.5-13. The performance in summer hot days in upper 80's during the day could not keep it near 70F(upper 70's). We run the AC from May thru October to keep the pollen out with asthma and allergies. The two stage seemed to make sense for May/June, Sept/Oct.

As I understand the coil will need to also be replaced in the ADP along with the new outside condenser. Installer said can use an ADP coil to match or swap with one from condenser manufacturer - any opinions on which would be better?

I am also thinking to add a solar powered attic fan to reduce the attic temps in the summer. Ducts are insulated and Air Handler is factory insulated inside the cabinet.

Should I go with a 4-ton 2-stage or just go with a 3.5 ton single? Looking at 16SEER units. Nervous that another 3ton 2-stage will not be enough to handle the mid-summer load.
There seems to be some debate about whether the two stage will save you much. My electric rate is 18.5cents/KWhr.

How many amps can I expect the Copeland 2-stage scroll to pull in Hi/Low for a 4ton unit vs the single speed Copeland for 3.5ton?

If I'm reading correctly, you have a 2 zone system that's on (one) airhandler and 3 ton A/C.

The advantage of a 2 stage A/C with zoning is that it will run on low stage when doing the small zone, thus it's quieter.

A 4 ton is going to be too much for so many reason.

It sounds like you're border line. Can you insulate better? Maybe some awnings? Better attic ventilation.

What kind of house do you have? 2-story, raised ranch or split-foyer?

 

[hardwired]

George, that's correct. One air handler in the attic feeding two zones. It's a raised ranch with walkout basement. There's a separate system for downstairs.

It's R38 in the attic ceiling already. Half the upstairs is cathedral ceiling so I can't add insulation there. I do plan to add the solar fan in the attic.

The install cost isn't that much more between the 2-stage and single. I already have the Aprilaire 2-stage controls for the present system in place.

My electric bill is killing me. Whats the output of a Copeland compressor used in 4 ton two stage? How many amps do they pull in low vs high? I can choose between Goodman and York affinity. The York is more money.

 

[acwizard]

The question that I have is, how are you heating this space . Is the unit in question a heat pump.

 

[beenthere]

Has anyone determined why the compressor failed?

Good chance that your duct system/zone system may be the cause.

Putting a 3.5 or 4 ton on it, will probably kill make for a short compressor life on the larger units also.

Are you sure that the compressor isn't still in warranty?

 

[hardwired]

Not exactly sure why the Coleman failed but it wasn't cooling and I had it serviced. The tech found a pinhole leak on a pipe that went to the compressor. The unit was fixed and then several months later it would only run in 1st stage. It would keep trying to turn on 2nd stage but the compressor wouldn't turn on 2nd. Turning off for awhile would get it running again but then would happen again.

The tech changed caps and some components which didn't help. Eventually it would not even start in 1st. There may be a kit he could try but thinks the compressor is probably gone. Replacing the compressor is very expensive.

 

[hardwired]

The Coleman was installed summer of 2005. I can't find the warranty page. homeowner info says it's Unitary Products Group HATC-F036S. Compressor is Bristol TS.

Anyone know if the compressor is still in warranty?

As far as ductwork I know it was supposed to be sized for at least 3.5 tons with calc and was also going to be oversized to handle the zoning. How could the duct be checked.

 

[beenthere]

Your local dealer can run the serial number and find out if its under warranty, Can't remember anymore if they came with a 10 year warranty, or if a special package had to be bought to get the 10 year compressor warranty.

A static pressure check can tell if the duct work is sized right for it, or a larger unit.

 

[George2]

Has anyone determined why the compressor failed?

Good chance that your duct system/zone system may be the cause.

Putting a 3.5 or 4 ton on it, will probably kill make for a short compressor life on the larger units also.

Are you sure that the compressor isn't still in warranty?

I agree with B. T. If you have a 3 ton now, the chances of having large enough ductwork for a 3.5 or 4 ton are slim.

Is there a way of giving us supply (run) sizes and return air sizes? Pictures are always nice.

Check on the warranty, so many are 10 yr. anymore.

 

[ID10T]

Coleman units come with a 5 year compressor warranty, they only started enhancing the warranties this year, I believe. Coleman, Luxaire and York are all owned by Johnson Controls, Inc. Coleman and York should still be running the same warranties, thanks to Goodman leading the way in the Warranty race. I have NEVER been a fan of Bristol compressors, and it just being a "Bristol"
is reason enough for failure. I would agree with "beenthere" finding the cause is smart business, a zoning system that does not operate correctly or bypass correctly, will definitely short live the compressor.

 

[beenthere]

Coleman units come with a 5 year compressor warranty, they only started enhancing the warranties this year, I believe. Coleman, Luxaire and York are all owned by Johnson Controls, Inc. Coleman and York should still be running the same warranties, thanks to Goodman leading the way in the Warranty race. I have NEVER been a fan of Bristol compressors, and it just being a "Bristol"
is reason enough for failure. I would agree with "beenthere" finding the cause is smart business, a zoning system that does not operate correctly or bypass correctly, will definitely short live the compressor.

The 10 year compressor warranty has been available since they came out with their first 2 stage systems. Which were the Bristol compressor units back in 2004 or 2005. And have had the lifetime compressor warranty since at least 2006 or 2007 on certain upper end complete packages/systems.