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Pics are a bit small for me but looks good from what I see. I have installed a few XL20i's and on one house we had a 3 ton and 2 ton heat pump close together and if the foundation had been much lower the HO would have had a eye full of trane top side louvers out bath room window. They are gigantic regardless of capacity. 3 ton is a few inches taller than 2 ton and has same perimeter dimentions. On the pad note, we always use plastic pads as the "concrete/styrofoam" pads dont look as good and tend to crack/break rather than a plastic flex a bit if ground is not packed/leveled well. Had a few break in half as the irrigation/electricians/plumbers digging trenches before setouts and dont fill in trench enough.

Originally Posted by 54regcab

Only during times when stage 2 kicks in are you getting any benefit from the oversized high end system. A single stage 2.5 ton would have would have worked just as good, and yielded the same electric bills. The only difference is you wouldn't have the reserve capacity to hold the 72 degree setpoint during outdoor design tempatures.

3.7 tons cooling load sounds high for 2400sqft above ground @ 91 outdoor temp. Either somebody fudged/miscalculated the cooling load or you really do have a leaky house. I'm at 800sqft per ton on my own house (2 tons, 1600sqft) and it will keep it 75F indoors when it's 100F outside. Typical 1999 construction, not super tight but not a sieve either. People tend to turn thier thermostats down to 72 to compensate for humidity issues, if the AC is running wide open to hold 72 it's too cold for most people.

I too question the low static values, did you take the readings with a wet coil?

You are assuming that high stage does not run very often, which is not the case on most days after mid-June around here. On milder days the low stage compressor handles the load nicely. A 2.5 ton may have covered the cooling load on many days, but during the heating season I would be using a lot of strip heat. My electricity bills went down a good bit compared to the older 10 SEER single stage 3.5 ton heat pump it replaced (especially during heating season). My goal was to have a system that could maintain the set point during worst case design conditions; that was achieved and I couldn't be more happy with the comfort the system provides really. Some people are fine with having the home rise to 76-78 deg during the hottest days but I am not. A 3 ton 2-stage also would have been undersized considering my heating load. While I understand your suspicions (I am just as against oversizing equipment), I'm confident in the load calc and system design. Static was measured with a wet coil (but clean filter) and is monitored/displayed by the equipment. 1600 cfm with a clean filter - .55" ESP. I replace the 4" filter every 4-5 months or so, before the ESP rises close to the blower's maximum capabilities. Keep in mind if the dehumidification mode is active then the blower will provide 1280 cfm on high stage. Better moisture removal and lower static.

Originally Posted by RyanHughes

3030 sq ft conditioned space (~600 of which being a partially below grade basement). Design temps were 91 deg outdoor for clg (although these past few summers we've had plenty of days above that) and 17 deg outdoor for htg. Indoor design was 70 deg winter and 72/50% summer. Total load was 3.7 tons and total cfm requred per Manual J was 1600 and that's what the system was set up for rather than the 1400 cfm. Luckily the home has a good duct system capable of delivering this much air, didn't need to change much of that except modify the return setup in the basement. Hard balanced system with no manual dampers, but very minor temp differences between rooms -- 2 floor house. Overall system works great summer and winter satisfying the temp/humidity set point and doesn't short cycle. FYI total net capacity of the 4 ton 20i heat pump is closer to 3.8 tons at ARI conditions.

Only during times when stage 2 kicks in are you getting any benefit from the oversized high end system. A single stage 2.5 ton would have would have worked just as good, and yielded the same electric bills. The only difference is you wouldn't have the reserve capacity to hold the 72 degree setpoint during outdoor design tempatures.

3.7 tons cooling load sounds high for 2400sqft above ground @ 91 outdoor temp. Either somebody fudged/miscalculated the cooling load or you really do have a leaky house. I'm at 800sqft per ton on my own house (2 tons, 1600sqft) and it will keep it 75F indoors when it's 100F outside. Typical 1999 construction, not super tight but not a sieve either. People tend to turn thier thermostats down to 72 to compensate for humidity issues, if the AC is running wide open to hold 72 it's too cold for most people.

I too question the low static values, did you take the readings with a wet coil?

Originally Posted by mark beiser

The way the refrigerant lines are run into the air handler would make me want to punch the installer in the nose if I was the service person that ever needs to work on the heat package, especially if It needs to be removed...

Agreed, they should have been run directly out to the left side and up. While there is more room to service them than the picture shows, removing the heater package could be challenging and may require some bending...

Originally Posted by 54regcab

How big is the house and what are your design temps?

3030 sq ft conditioned space (~600 of which being a partially below grade basement). Design temps were 91 deg outdoor for clg (although these past few summers we've had plenty of days above that) and 17 deg outdoor for htg. Indoor design was 70 deg winter and 72/50% summer. Total load was 3.7 tons and total cfm requred per Manual J was 1600 and that's what the system was set up for rather than the 1400 cfm. Luckily the home has a good duct system capable of delivering this much air, didn't need to change much of that except modify the return setup in the basement. Hard balanced system with no manual dampers, but very minor temp differences between rooms -- 2 floor house. Overall system works great summer and winter satisfying the temp/humidity set point and doesn't short cycle. FYI total net capacity of the 4 ton 20i heat pump is closer to 3.8 tons at ARI conditions.

The way the refrigerant lines are run into the air handler would make me want to punch the installer in the nose if I was the service person that ever needs to work on the heat package, especially if It needs to be removed...

How big is the house and what are your design temps?

Originally Posted by tedkidd

Like the bottom/side return setup. Guess that's pretty close to ok:

It'll be interesting to see how much it runs at 4t, or if that's overkill/missed opportunity to get a lower low. You able to see run graphs?

No runtime graphs, but from my experience thus far, when the outdoor temperature is 45 deg or above, the 2 ton compressor handles the heating with long cycles. Lower temperatures, the 4 ton compressor is likely to engage for roughly 8-10 minutes to help out. It hasn't gotten nearly as cold as it can be yet (lows have been mid-upper 30s). So I suspect the 4 ton compressor will be used more often in Jan/Feb when it's real cold. Heat loss was about 45k, give or take, which is the high compressor ARI capacity. 15 kW of electric heat that hasn't needed to be used yet. System was sized by the Manual J results, and the actual capacity of the 4 ton 20i matched the home's load quite closely, but part of me does now think a 3 ton would have performed adequately at least close to design temperatures. I didn't want to go smaller because I wanted to ensure I could maintain 72 all summer and 70 all winter. But seeing the 2-stage operation in action, you realize the low stage compressor, by running its long cycles, really reduces the calls to high stage needed -- even at fairly cool/warm ambient temps. I've been happy with the improved comfort over the previous system it replaced... it'll be interesting to see how it does this winter and next spring/summer (summer use this year was limited).

Originally Posted by RyanHughes

Hyperion air handlers can do side return. Works well when you are limited with verical height. Over 1200 cfm you need to bring in return under the unit too.

Like the bottom/side return setup. Guess that's pretty close to ok:

Total static on high stage (1600 CFM) was around .55" with clean MERV 10 filter (.15 on low - 800 CFM).

It'll be interesting to see how much it runs at 4t, or if that's overkill/missed opportunity to get a lower low. You able to see run graphs?

Thanks La. The basement carpet is a darker green shade, so I guess the air handler does match its surroundings quite nicely.

nice job Ryann.
you can take credit for hiring a company
who takes pride in their work.

maybe a nice cool sage green would be more
of a complimentary color match.

i *personally* must take exception with the color, i don't think the contractor matched the color scheme of your basement correctly. they must be unliscenced/nonunion/daylaborers from home depot. there's ansi regulations regarding color choice, clearly violated here. a real pro like me would never make such a *pft* obvious mistake.

Originally Posted by sarge

The side they put towards the wall is the side that needs room to swing open for cleaning; condensing unit photos. Not cool IMO.

There is plenty of space on all sides of the unit for service and cleaning. We were careful to make sure the service panel (to the left of where the lineset comes in) had plenty of clearance. How much space do you need? Was not going to install the unit in the middle of the side yard, and there wasn't much of an option to move it either. Anyone else want to find something to nitpick about? (Jimmy did make a valid point about the pad with a heavier unit like the 20i -- I do appreciate the feedback. But the unit is fine and stable on the current pad.)

By the way, the panels don't swing open. Not a Lennox. Although I was strongly considering the XP21. Chose the 20i for several reasons, including: 1. preferred the aluminum coil and EEV of the TAM8 over copper coil and generic TXV used in the CBX32MV for years, 2. could do side return with the TAM8 -- height was an issue and the Lennox would have been a tight fit, and 3. wanted the dual Climatuff compressors for better dehumidification and staging. I like the longer runtimes achieved with the 2 ton compressor, whereas with the Lennox or any other unloading scroll system I would be at ~3 ton capacity on low. Manual J called for 3.7 tons/1601 cfm to maintain 72 F db/50% RH. The 4 ton 20i was a great match providing ~46,100 btuh cooling @ 1600 cfm. The system has been working well in both cooling and heating modes so far. I really like the features of the ComfortLink II communicating system: tells you superheat, EEV position (/500 steps), coil temperature, DAT, ESP, blower RPM, and much more...

The side they put towards the wall is the side that needs room to swing open for cleaning; condensing unit photos. Not cool IMO.

We use solid concrete ones on larger heatpumps. Some of the big ones weigh 400lbs.

We have been using the composite plastic pads on most of our installs for 4 years now and have never had one come back smashed or bent in. I think its a good alternative to concrete. I know the guys like it much better! LOL

Originally Posted by treysdad

Just glancing through the pictures, seems like the return is extremely undersized, which makes me wonder how you got such great #'s on the static pressure. I know you said an electrical disconnect was installed, but I did not see it within easy reach of the condenser, or even mounted outside looking at the pictures shown. Also, from what I saw you had a honeywell F100 series 4" media filter installed. The 10 MERV rating is not a true rating, test it after 2 weeks of running. The biggest cause of air condition failure is dirt, so if you put such a good system, why not protect it properly? Just saying. Also, there is no problem with a plastic pad, as long as it is a good style and not a cheap one. It makes it easier to relevel should the ground settle. Lastly, it should be raised off the ground for easy drainage and a minimum of a few inches off the ground, or a minimum of the height of a normal snow fall.

I don't know where you get "extremely undersized" from -- maybe it's hard to see the return in the pictures. The return includes a 20x14 duct serving two central 22x22 return grills upstairs and downstairs (split trunk). A separate 6" flex return was added to the basement on a 12x12 grill. Being such a short, straight run, the 6" flex was providing 200-250 cfm when we tested the entire duct system using a flow hood. Did not want to make the basement too negative. This in addition to the existing 20x14 was fine for 1600 cfm at reasonable static when tested. The system spends most of its time at lower demand airflow anyway.

The disconnect is hard to see, but in pic 7 it's behind the slim duct covering the lineset.

The "MERV 10" filter after about 7 weeks has begun to load up a decent amount (evenly at least). I was considering just replacing it with a MERV 8 filter for a bit less pressure drop. What are you recommending instead of the MERV 10 filter?

Trane Heat pump

Just glancing through the pictures, seems like the return is extremely undersized, which makes me wonder how you got such great #'s on the static pressure. I know you said an electrical disconnect was installed, but I did not see it within easy reach of the condenser, or even mounted outside looking at the pictures shown. Also, from what I saw you had a honeywell F100 series 4" media filter installed. The 10 MERV rating is not a true rating, test it after 2 weeks of running. The biggest cause of air condition failure is dirt, so if you put such a good system, why not protect it properly? Just saying. Also, there is no problem with a plastic pad, as long as it is a good style and not a cheap one. It makes it easier to relevel should the ground settle. Lastly, it should be raised off the ground for easy drainage and a minimum of a few inches off the ground, or a minimum of the height of a normal snow fall.

Cool. I had a Ryan in my class when I went to ACCA.

Was wondering if it was yourself.

The company is actually a member of ACCA, however.