[jasonhomeowner]

I am sure that this information has been covered, I just cant find it. My HVAC company installed a new system in my home. I asked for a 15 seer goodman 3ton unit. we agreed on the price and his team came out in a few days. They installed outdoor unit model ssz140361ba, and indoor unit avptc313714aa. Those are the model numbers from the units themselves, however the AHRI certificate of product ratings show slightly different numbers ssz140361a and avptc313714a. The energy star rating says that the outdoor unit is a 14 seer unit. I was told by the company that the unit was variable speed and had a txv and this qualifies it as a 15 seer...... now the questions.
Does the slight variation of the model numbers make a difference?
Why does my unit say its 14 seer when i asked for 15 seer?
Does variable speed blower and txv make an increased seer?
If so, how can i tell if my unit is indeed a variable speed blower and includes a txv?
Who is AHRI and what is the benefit to the homeowner to have a certificate of product ratings anyhow?

 

[2old2rock]

Not familiar with those model numbers, but yes, a txv and VS blower can up the seer.

 

[BaldLoonie]

AHRI certifies the efficiency and performance of a SYSTEM. You have to look beyond the 1 component, in this case, the outdoor unit. As a system, with the indoor unit in the equation, you have a 15 SEER, 13 EER, 9 HSPF nice efficient system. The AHRI certificate is used to tell what you are getting. Normally needed with a utility rebate or back in the days with tax credits.

The AVPTC is a top of the line air handler with variable speed blower and factory installed TXV. Those components are what turn the "14 SEER" outdoor unit into a 15 SEER system.

 

[tipsrfine]

What SEER number is marked on the equipment doesn't mean much at all if it isn't connected to a duct system that is sized & designed correctly. And charged correctly. Do some googling on what the odds are your ductwork is going to allow your new equipment to even reach 80% of its efficiency rating; some numbers put your odds at 1 in 10. I'd be more concerned about being lied to, or kept in the dark, on that issue.

 

[jasonhomeowner]

What SEER number is marked on the equipment doesn't mean much at all if it isn't connected to a duct system that is sized & designed correctly. And charged correctly. Do some googling on what the odds are your ductwork is going to allow your new equipment to even reach 80% of its efficiency rating; some numbers put your odds at 1 in 10. I'd be more concerned about being lied to, or kept in the dark, on that issue.

with that thought in mind. we did increase the size of the unit from 2.5 to 3 ton. Understand our house was purchased new from a builder that did everything bare minimum. after purchasing our home we turned the garage into a bedroom adding 250 sq feet under air. When we made that addition we had an hvac contractor come out and add a vent to the garage bedroom. that contractor told us that it was likely that our unit would not cool as well and was undersized. Turns out all of the contractors agreed with that one and said our original unit was slightly undersized and a 3 ton would be better, but any higher and we run the risk of "short cycling" whatever that is. With the instillation of the new unit we increased the size of the return and added more two more vents, one to the "Garage bedroom" and one to the main living area of the house.

 

[tipsrfine]

with that thought in mind. we did increase the size of the unit from 2.5 to 3 ton. Understand our house was purchased new from a builder that did everything bare minimum. after purchasing our home we turned the garage into a bedroom adding 250 sq feet under air. When we made that addition we had an hvac contractor come out and add a vent to the garage bedroom. that contractor told us that it was likely that our unit would not cool as well and was undersized. Turns out all of the contractors agreed with that one and said our original unit was slightly undersized and a 3 ton would be better, but any higher and we run the risk of "short cycling" whatever that is. With the instillation of the new unit we increased the size of the return and added more two more vents, one to the "Garage bedroom" and one to the main living area of the house.

I mostly made my comment for the benfit of any other homeowner reading this thread because people get misled about all the talk of "equipment" efficiency ratings, but there is often no mention in the thread that the "equipment" is only as good as the duct system it is attached to. You mentioned the builder "...did everything bare minimum"; wouldn't you agree that your homes "envelope" is bare minimum? When all you have is a hammer, everything looks like a nail. Bumping up the a/c by a half ton is one solution, improving your homes envelope is a better solution and, depending on what you did to improve it, could have resulting in you bumping DOWN by a half ton. I'm not making any specific comment you your particular situation, and you may very well be fine. Just trying to help.

 

[udarrell]

Turns out all of the contractors agreed with that one and said our original unit was slightly undersized and a 3 ton would be better, but any higher and we run the risk of "short cycling" whatever that is.

With the instillation of the new unit we increased the size of the return and added two more vents, one to the "Garage bedroom" and one to the main living area of the house.

Adding ducts & supply diffusers could help deliver the needed CFM for the 3-Ton system.

Depending on the climate you live in; you could also check the delivered airflow CFM & set it for 350-CFM per ton or, 1050-CFM.
What state & large city do you live in, or near?

How much filter area does it have & what type filter are you using?
Hope not a one inch deep pleated filter.

Installing a cycles per hour or SWING temp room thermostat can allow you to adjust the length of runtimes to reduce short-cycling with differing outdoor temp conditions. ACE Hardware has a good low cost temp-differential SWING adjustable TH.

 

[jasonhomeowner]

Adding ducts & supply diffusers could help deliver the needed CFM for the 3-Ton system.

Depending on the climate you live in; you could also check the delivered airflow CFM & set it for 350-CFM per ton or, 1050-CFM.
What state & large city do you live in, or near?

How much filter area does it have & what type filter are you using?
Hope not a one inch deep pleated filter.

Installing a cycles per hour or SWING temp room thermostat can allow you to adjust the length of runtimes to reduce short-cycling with differing outdoor temp conditions. ACE Hardware has a good low cost temp-differential SWING adjustable TH.

I live Near Daytona Beach FL. We are using a media filter for allergy reasons. filter measures approx 22x24x5 inches thick.
We are using a Honeywell TH3000 thermostat that appears to not cycle per hour setting on it.

 

[wahoo]

According to Goodmanmfg.com site your new system is truly rated at 15 SEER, 13 EER, 8.9 HSPF, AHRI #4432057 so you truly did get the efficiency they quoted you. The change to this variable speed unit raises the SEER rating to 15 from 14. As to the "cycles per hour" thermostat, please remember you may have (more than likely will have), more variation in the indoor temperature (and comfort) if you go to this type of thermostat. As long as you are happy with the system I'd stay with whatever the contractor installed. If you change the thermostat, you'll be responsible for whatever happens after that. Good job!:.02:

 

[jasonhomeowner]

utergreet:Thanks to you all for your reassurances. I am sure that everyone here knows what kind of investment a new unit is, so i was understandably apprehensive when i did not understand everything. I have a new question... slightly more technical in nature. When I changed the garage to a bedroom i turned the indoor unit area into a closet. (wish i had a picture) The old unit was a tiny little rheem that took up almost no space. The new unit with the 5 inch air cleaner on it was too tall so they dismantled the box underneath the old unit. The young man that rebuilt the box underneath used the concrete floor as the bottom of the new box and placed fiberboard around the walls and then used a very thick plywood for the top. However the concrete floor has the chase tube coming out of it which was full of mud and moisture. he also did not seal the fiberboard (tape and mastic? around the edges) so now i wonder if my return is pulling air from my walls and up to my attic?(behind the fiberboard was only my insulation and the studs) i also am concerned about a mud moisture filled pvc tube being part of my circuit of air. am i crazy or did what i say make sense?

 

[wahoo]

Get a few tubes of Airseal #11 duct sealer and seal this all up. This stuff is great sealer and made to seal joints and seams. I'd use it to seal the chase tube also. Since it is in the return, you could also use simple latex/silicone caulking you can find at any hardware store. :.02:

 

[jasonhomeowner]

Thanks Wahoo... Update i contacted the contractor and voiced my concerns. The contractor came out the same day to see what i was talking about. He apologized for the lack of attention to detail. He sent his employees that afternoon and they sealed both the chase and the "box". I am very happy with the level of customer service i have gotten so far. I live in west volusia county FL and if anyone is looking for a fair company in that area with great customer service i would be happy to recommend them to you.

Pros about the company i used.
They tried their best to explain everything during the bidding phase.
They answered all of my questions that i asked them.
The price was fair, and was inclusive of a labor warranty.
The customer service after the install was great.
During the install the owner of the company came out and played a board game with my son.
over all its hard to be happy when you spend so much money but they have made it bearable.
The company i used is but feel free to shoot me an email.