Return grill size for 5 ton unit. It has always worked.

Return grill size for 5 ton unit CFM Chart for SQUARE Return Air Grilles. The air supply and return lines (tubes) under the house both say 14" on them. 5 ton unit, depending on the climate. temp split 12* The most common place you will find furnace filters are either in the unit or in the return air ductwork right next to the unit. (1380 s. Her Table 4. Me personally I would lose the filter at the air handler and only use the cheap thin fiberglass at each return filter grille allowing my return ducts to remain clean and will be less restrictive than those thick pleaded cabinet filters assuming that's what's at the unit. Now with your return sizing your static pressure is going to be really high and your not going to be pushing that now. 5-Ton system, that would mean 25X20 2. The outside unit is a 3 ton with a inside air handler of 3. My furnace closet is in the hallway. Calculating the return air duct size is simple. But again, as others have stated, what is between the grille and the plenum has just as much to do with the return air volume as the size of the grille. I only know the size of filter, and it worked fine with a bigger "I think 500 sq inches per ton is the standard. Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! Unit Converter Temperature o C K o F. Can you get that online from Trane? Your return air grille size depends on the size of your AC unit or the measurement of your return air duct. Returns not too bad. 5 Ton Window Ac Front Grill ₹ 1,500/Piece. Download also the calculation in Pdf. Proper sizing of the return air filter grille is required for the furnace to function correctly. I am having new duct work installed as I type. At 350-400 CFM per 12,000 BTUs of heating capacity, there’s enough airflow to circulate heated 400 sq. Sizing an HVAC System. " Does this mean if my unit is a 5 ton unit, there can be up to 5x500=2500 sq. 1600 CFM / 300 FPM = 5. It should either be replaced with a 20" or a second 14" duct should be added. Design the Supply and Return Grille Location. Hello all, this is my first posting so be easy on me. Inside that box which is beside the air handler there is only one opening that lets the air flow under the air handler it is 18" wide x 9" tall opening. We currently have only 338 sq". 05 inches of pressure drop per 100 ft. inches of return filter and makes 0. Basement : 1. in. if possible 6ft. The first until services the LR/DR/Kitchen/Den, all fairly open areas. The last step is to size the return grille and duct to match the total of the supply registers. Air Filter Rack Sizing Air Filter Rack Sizing for efficient operation - Size Gross Return Air filter grille area for 200-sq. Smaller units keep stable temps, dehumidify better, run I have a 5-ton hvac with a 24x24 (576 sq inch) return grille. If you have an existing vent, The size of the return air duct you would be getting for your 5-ton unit depends on if you would want a round or rectangular duct; the timely round return for your 5-ton unit is 2” in diameter, while for a rectangular duct, you What size duct work do I need for a 4 ton unit? You can never have to much return air, as a HVAC contractor you want no less than 144 square inches per ton. 5 ton AC, the furnace manual states there must be a minimum of 250 sq. That being said, a 20x20 will work for a 3 ton unit, it will just get dirty sooner, and it should be a standard fiberglass filter. The stale air return is a 20" x 20" opening in the ceiling. My contractor is insisting that 16" flex is adequate and that I should trust his 50 years of experience. Example: The total of the supply registers in the pressure zone equals 340 The minimum free air return is around 144 square inches per ton. Everything I've read on HVAC forums says I need 1200 CFM for a 3 ton unit and that equates to 18" flex duct. 5 ton unit have less than a 20x20 filter. For example, a 2-ton system might require a return duct with a size of around 16 inches in diameter. The location of the supply and return grille determines how you will run the supply and return duct. that said, what is the minimum minimum plenum size for 4 ton unit; Cookie You're looking for 250-300fpm at a filter grille. in) Grille Size (in) Airflow (cfm) 36: 6 x 6: 38: 64: 8 x 8: The 30"x 20" return grill is standard for a 5 ton system and probably 90%+ of 5 ton units in the valley have 30"x 20" return grills with no problems. I had a 3 ton ac a home and it had a 20 x 14 return grill and and an 18" duct. The basement is a walkout basement. Most common return grill size for 1. also installing two 6,000 btu wall units in finished basement about 500 sq ft. Alternatively, the scale is The total number is determined by the unit size of the AC, heat pump or air conditioner in tons/BTUs. 0 noise. 10 Return air intake (non-engineered systems). 7 inches [18 mm] W. The return grille area will drop it 25% to . 30×30 is your best bet. 2 Return Air Duct Installation Sizes (Based on . size Using 2. The next column is Undersized return air ducts result in the ducts and grills being more noisy than usual and the air conditioner components becoming stressed, thus reducing the lifetime of the unit. The 30"x 20" return grill is standard for a 5 ton system and probably 90%+ of 5 ton units in the valley have 30"x 20" return grills with no problems. It will make for a quiet and very efficient How can I determine if my home has enough return to run a 3-1/2 ton unit correctly? I'm a homeowner with no background in HVAC. 5 tons model #4TEE3F40B1000AA. Size and capacities of air return intakes. The Size Of Your Return Ducts. Static Pressure which is currently . From here, professionals will determine the size of your A return air duct size calculator helps you determine the ideal dimensions based on various factors, including the area of the space and the desired airflow rate. My home originaly had a 2. The size shall be sufficient to return a volume of air There seems to be different data on the correct size duct for return sizing on a 4 ton unit. The distance from the return grille, in the ceiling, to the evap coil opening of 22x26, is approx 10 ft. The most common place you will find furnace filters are either in the unit or in the return air ductwork right next to the unit. ESP 1. size for return plenum. 0 SEER/11. For example, if you are checking a 3 ton system, the airflow required is between 1050 and 1200 CFM. I. In a typical residential house, I have rarely seen one that even has enough room for 5 tons worth of ductwork which is ok because I’ve rarely seen a typical residential house that needs 5 tons worth of AC. The return duct size of 16 inches is insufficient for a 3-ton AC. Using 2. 5 ton heat pump and I am questioning if my return ducts are too small. Now granted stage 1 is running in 3tons and I only see 5 tons when stage 2 kicks in. However, the size of the return platform entry is only 23 x 13 (299 sq inches). 5, 3, 3. Your 5 ton unit has 516. 5, 4, 4. So, for a 5 ton unit you will need 5 X 144 = 720 square inches of filter for this This is the required airflow through the return grille. 5 ton system. 1 inch [3 mm] W. 5 ton system A 12x18 return filter grille is good for about a 1 ton system. At 4 tons standard air flow on a 30x16 you’re looking at ~686fpm face velocity. So what is my return size, 576 sq inches or 299 sq inches?. I was told this by a contractor: 3 ton heat pumps with the new r410a refrigerant recommended size is 18" on the return duct. Otherwise you should expect issues with your system typically in winter time. Below, you will find 3 grille size CFM charts – 1st one for horizontal As David Richardson notes in his article on return grille sizing, the best way to go about sizing a return grille is by looking at your target feet per minute (FPM), which is determined by Manual D to keep the noise down. According to my calculations, the correct interior size should be 10x18 (180 in2. 5, 5, and 6 ton units (CFMs, Your 5-ton unit ac would need a return duct size of 22” diameter for a round duct and 19”×19” or 20”×22” if you want to install a rectangular duct. 5 16 500 2. View Profile Package Units, Furnaces; Geothermal / Water Source Heat Pumps; Specialty Systems; Boilers – Hydronic, It has a 4 ton and 2. The filter is a 6673 Lennox Merv 11 that is 20 x 25 x 5 inches. Also, the manual on that air handler is missing. Should I insist on the 18" flex return? I am going to I am trying to improve air flow for a 5 ton horizontal unit located in the attic. 5 20 800 Not applicable to systems with nominal cooling capacity greater than 2. On Our 2. inches of free air space in the upper portion of the furnace closet door and 6 inches between closet door and front of furnace. The grille size chart tells you what grille size you will need for your HVAC system. A 4 ton unit is a nominal 1600 Cubic feet per minute (installers may set it to 350 cfm per ton for a total of 1400 cfm depending on specific need). (Ton)* Minimum Return Duct Diameter (inch) Minimum Total Return Filter Grille Gross Area (inch) 1. Using the right duct size can significantly enhance the performance of your My opinion is 12" is woefully to small along with a 14x14 grill. Measure the return air grille openings and multiply by . Giving the 2 ton system a 12 inch return to a mixing box then 10" to the return grill, I added another14x 14" return air filter grille with 10" duct back to mixing box , still only 12" to the unit, I had to reduce fan speed to low to prevent it freezing up and suction pressure dropping below minimums. single level home servced by 2 - 3 ton AC unts. Is using an 'on the unit' filter for a system of this capacity appropriate. How much return grill area should this system have? I currently have 423 sq. 5 ton. We are replacing a gas pack that is currently a 2 ton Trane and going with a goodman 2. 0-D: Return Duct What size Filter should I have for a 3 Ton Heat Pump A/C System? I'm getting quotes about putting in a new 3 Ton System & the Tech told me I had to cut out a wall in my Closet (next to Unit) and put in a bigger Air Filter. It should either be replaced with a 20" or a second 14" duct If you are not dissatisfied with the noise you could stick with only one return air grill. inches and sounds like a hurricane. Step 1. Unico supplies factory made components for the complete return air system that includes the return air box with grille and filter, return This is the required airflow through the return grille. Here’s the issue, the return duct that is in the wall is only 24” x 10” x 36”. On 2014-06-18 by Reg. Duct I just had a new 4 ton heat pump with vs air handler installed. Return duct temp was 92 and vent was 72. That is the part number for the indoor coil. First, let's 12" flex at the recommended residential velocity of 600 Ft/min gives almost exactly 500 cfm. 2. Edit or delete it, then start writing! Only difference is #1 (cheaper bid) says return grille size is just fine. The old unit had a odd size filter, like 22 1/4x 22 1/4. 25 DIFFUSER BOX ALUMInUM DIFFUSER AnTI-SWEAT GASKET Model # CFM Stati P reu throw in Feet ne k Size 01-510-22 47 5/8 35 5/8 23 1/4 33 45 4 1/2 18 2 1/4 28 2 1/2 18x28 RETURn TRAnSITIOn (15 TOn AnD I am on the west coast of florida. For a 2. It runs forever during the summer and the house really never heats up well in the For example, a 5 ton unit should have a 30x36 grille(2-18X30 filters). Let's say you have three supply registers, each feeding 150 cfm (cubic feet per minute) of air into a room. 5 ton a/c need a bigger return grille then 18 by 24 filter. But all is good. Straightening the louvers increases free area. Two of the bedrooms, each about 250 sq. Its not so much the return duct, its the filter grill size, thats the restriction, 20 x 25 return grill id say is the min. A common rule of thumb is to aim for approximately 400-450 CFM (cubic feet per minute) of airflow per ton of HVAC capacity. Return air grilles are typically sized based on a face velocity of 500 fpm and a free area of 70%. The rule of thumb for returns is 2 CFM for each square inch of grill. I am curious because the cross-section of the filter box is limited to more In the quest for the ideal return air grille size, a comprehensive set of sizing guidelines and a well-constructed CFM chart become invaluable tools. I am using 160 sq. per ton. The second unit services 3 bedrooms. The duct work and air handlers are in the attic. Thanks! Been a while but I need some help! We are having a 5 ton 2 stage Carrier unit installed in our home. I just want to make sure the contractors who are quoting a replacement unit for me are being straightforward. Is this system shared with one or I currently have a 3 ton with 16 inch metal return duct work. temp split 12* Tighten up the house/ductwork and downsize the HVAC system. ) It should also step down in size after removing the first half of air, correct? I would size the return for that all the way, including an oversized filter rack. 600 fpm is not all that fast so that's why it doesn't "feel" strong. Is this enough return for a 4 ton package unit? I am having a 24 x 30 filter grill installed. I would go higher if you can. Sometimes you can even use the grill cover to cut down and open airflow, but the whole process will be more efficient with dampers. Proper sizing and orientation of grilles, registers, and diffusers may seem like such a simple thing, but it's an area where confusion and mistakes are commonly made. They have a 16” x 32” return grille which isn’t enough cfm for 5ton. 3 [8 mm] to . ft. It is about 12" long, with no step down in size. Each ton of an air conditioning unit’s cooling capacity can cool about 400 The lazy air return options are door undercuts, leaving doors open, and transfer grills installed through or above the doors. If the filter describes the air handler return plenum size there's the answer. Download Free MEP Calculation Excel Sheets, AutoCAD Drawings, Plenum box sizing for fan coil unit (FCU): As per Ashrae I have a Comfortmaker 2. It runs forever during the summer and the house really never heats up well in the It has a 2 ton Skymark HVAC unit that produces 750 CFM for heat and 800 CFM for A/C. The best method for determining system size is to use a Manual J load calculation for the entire home or building. It uses a long list of inputs such as square footage, layout, insulation, window quality, climate and much It is a small single story bungalow with a Ruud 50,000BTU furnace w/ 2 Ton of air. 5-ton: 14: 13 by 12 14 by 1115 by 1017 by 919 by 823 by 728 by 6: 2-ton: 14: 14 by 1315 by 12 17 by 1118 by 1021 by 924 by 828 by 736 by 6: Everything I've read on HVAC forums says I need 1200 CFM for a 3 ton unit and that equates to 18" flex duct. WxH WxH WxH WxH WxH WxH WxH WxH 80 6x6 7x5 9x4 90 7x6 8x5 10x4 100 7 8x6 9x5 11x4 125 7x7 9x6 11x5 13x4 150 8x7 9x6 12x5 15x4 175 8 I'd size the two Return-Air grille racks at least 20X25= 500-sq. in is more than 160. Let me ask you thiswould a 3. My furnace has two 16"x20" return air grilles on the front of it with 2 filters of the how important is the size of the grill? its only about 12x18 for the main return but duct work is 18x8. 1 Submittal-drawings Contents Document Number Title Mini-Mate Component Location DPN004808 Evaporator Unit, 3-ton DPN004179 Evaporator Unit, 4-ton and 5 Plenum box sizing calculations for AHU and FCU . per ton for return air sizing. (30x36)/144*288=2160 max cfm. 5 and 2 ton systems is 12 x 24 filter grille. Return Air System. When using duct mounted filters, Our 2. This Ruud unit was/is located in the attic and was not affected by the I used Hart & Cooley engineering data for the return air grille sizing For the FLEX-DUCT RETURN-AIR SIZING, for your 2 ton condenser I would always use 900 CFM when Original unit was 3 or 3. A single 16" flex duct is good for ~1000 cfm or approximately a 2. So the true answer to the question is not how many square inches but really, What size Filter should I have for a 3 Ton Heat Pump A/C System? I'm getting quotes about putting in a new 3 Ton System & the Tech told me I had to cut out a wall in my Closet (next to Unit) and put in a bigger Air Filter. Situations may arise where you want or need to install the filter at the return air grille. 7=336in² 500fpm or less is suggested on non filter grilles. 02" sp) with (10) feet of 24x12 duct (-. The have had air flow issues and it’s due to their return grille. 0 HSPF @ 1,750 CFM. ins. (9' ceilings) have 2 - 4" x 10" supply The return grill CFM calculator is an essential tool in the field of HVAC, facilitating the accurate measurement of airflow in a given space. as long as 7 outlets per nominal ton (2 outlets per nominal kW) are used and the plenum is acoustically lined or made of fiberglass duct board. My Air Filter is a 25"X16"X1" Is this too small for a 3 Ton Unit. 5 ton has 750 sq. of total Return Air vents/ducts? Thanks for reading if you made it this far and for any advice on the duct/grill size that might work. There's 313*AV048070 and 313*AV048090. Her I currently have, in the attic, a 2" duct board supply trunk, with interior dimensions of 12x20", giving an area of 240 in2. In applications of limited space, the disposable filter may be located in the return duct. My understanding is that you need 500 sq inches for grille size and i'll need a total of 1000 CFM. It worked for 13 years with my old 3 Ton Unit 10 Seer. Probably not. If you are not dissatisfied with the noise you could stick with only one return air grill. A 3-ton AC should have a return duct 18 inches in diameter. of return vent adequate in a heat pump unit with a 20x20 air return filter. Based on a 4 ton, would a 18" round flexible duct be sufficient CFM for a 4 ton unit? The return grill size would be 24x30. the air handler is in the attic and the other big machine is outside. 5 EER/8. Generally: 200 sq. The target FPM from Manual D is 400. Further on, you will also find a very helpful return duct size chart for 1, 1. Was told by a contractor over the phone that based on my s. Chances are, that return grille was sized too small. So 24” x 10” rectangle duct is not big enough to allow the amount of cfm I need for the 5ton unit. 5 to 5. He said that a 20x25 is 1000 CFM and a 4 ton unit requires 1600 CFM. So, draw the supply and The size of a return air duct should generally be based on the HVAC system’s capacity. 5 tons or less than 1. It’s just going to look big lol, some people just don’t RETURn GRILL 2. Reply The total number is determined by the unit size of the AC, heat pump or air conditioner in tons/BTUs. Then, you look at a manufacturer’s return grille performance sheet and pick a grille that satisfies the FPM and your CFM Return air duct size for 1-5 ton ACs is 14” to 22” for round ducts and 13”x12” to 32”x12” for rectangular ducts. The return filter is on the unit between the return plenum and furnace. example: 4ton x 160sq. The unit spec is to run at about 2200 cfm at max cool. 0 tons, or 18,000 to 60,000 BTUs. For a 3-ton AC unit, it's best to have a return grille totaling at least 600 square inches. Minimum Duct Size (Square inches) Minimum Return Size (Square inches) 1 72 200 1 ½ 108 300 2 144 400 2 ½ 180 500 3 216 600 3 ½ 252 700 4 288 800 5 360 1000 M918. in: Home & Kitchen. Manual "D" will dictate duct size. Plenum box sizing calculations for AHU and FCU . 5 ton ho unsure. Thanks! The return grill size matters. It uses a long list of inputs such as square footage, layout, insulation, window quality, climate and much A 5 ton is way over kill for you house. , then the filters vary as to how much more the Return area is reduced & the velocity is increased. I also have 3 air returns and like 30 supply vents. When the return is too small the system is essentially “starving” for air. 02-23-2005, 11:33 PM #2. Use the return air duct size calculator below for accurate dimensions required for your air conditioner or Check the return grille size CFM chart. He told me that all the numbers are suede because of the What size return air grill for a 48000 BTU heating system? 48,000 btus is equal to 4 tons of air flow, 12,000 btus per ton. I heard that a 5-ton hvac needed at least 1,000 My contrator suggests that I add a 14" duct return. Hopefully, you'll have a 3 ton outdoor unit, if it is a 4 We are replacing a gas pack that is currently a 2 ton Trane and going with a goodman 2. I wanted to verify with you guys since the cost of upsizing the ductwork is high in this quote, whether it Recently replaced my old 2. This comes in handy if This means a ductwork size for a 5-ton unit of 2,000 CFM will branch out to deliver 500 CFM to each room. Currently have a three-ton unit. What size return grill do you need for a 15' x 17' downstairs master bedroom Table 4. For a 3-ton AC, a 16-inch return duct is too small. I had read that a 2. you will want Installer is using my existing attic c/a duct work for mitsubishi 3 ton compresser with 2 ton air handler. 5 ton unit needs (400 sq' per ton). 0 18 600 2. Each run might look reasonable and there are registers in all of the rooms, but the main question should be, David explains return grills, return grill whistling. Units with coils should be applied with a minimum of . You shouldn’t have issues with the filter if you open the return up to 36x30. Air-cooled Ductable packaged units by Voltas are available in Table B. Regarding the 3. I would increase the size for sure no matter what even if you put an MFRFG SERIES RETURN FILTER GRILLE SPECIFICATION CHART B A 1-5/8 C MINUS 2-3/4 C 1-5/8 D MINUS 2-3/4 D • Heavy Guage Steel Construction • Concealed Hinges The minimum recommended filter area is 2. I find it hard to believe that its a size problem (you've got enough grille for a 1. We don't know what your supply air cfm is and what your return cfm will be. 5 cubic feet per minute (CMF) per square inch of the filter area. With the increasing emphasis on optimal air circulation in spaces, understanding How Do You Calculate Return Air Duct Size: 3 Step Guide. If only one central return air grill is installed, it shall be of proper size. CFM I have used this formula to size many HVAC systems. The can size at 14x24 is plenty as well. 5 ton unit. Residential systems range from 1. The contractor said he would build frame out of wood and line with sheet metal. For my 2 ton unit (moving 800 cfm), specify a method for determining the size of the transfer grille or door undercut. 25 sq. 5 ton unit with a 3 ton and the 3 ton is cooling the temp great. UNIT Return Air rom All Zones Ultra-Zone™ Zone Control Panel 24vac Power C o nt rl W i g Su ply Air Sensor (required) R D-H I D-H ND-HD Hand Damper Return Air Sensor opti nal) M P Ultra-Zone™ 6ft. So, draw the supply and Tighten up the house/ductwork and downsize the HVAC system. Is the the size of a 14" duct 196 sq inches? Am I additional return ducts were added in the attic to get proper flow, but the plenum was not done right. I have two 20X20 returns the unit will pull from. I have installed supply ducts in the basement. First contractor I spoke with walked thru the home, did a load calculation and came up with three-tons. (In multilevel homes, a central return should be installed on each Hello All, I have 3 ton system in basement , my house is approx. If lowering the static on the return side is more important, I can flip it. Open up the A 16” return duct on a 3. It has always worked. WxH WxH WxH WxH WxH WxH WxH WxH 80 6x6 7x5 9x4 90 7x6 8x5 10x4 100 7 8x6 9x5 11x4 125 7x7 9x6 11x5 13x4 150 8x7 9x6 12x5 15x4 175 8 For ducting, I put the return on the back side so all the duct runs could be straight. So, draw the supply and Installer is using my existing attic c/a duct work for mitsubishi 3 ton compresser with 2 ton air handler. 5. I would increase the size for sure no matter what even if you put an Dark Mode; Light Mode; Menu Log in Determine the size filter needed in square inches The standard in the HVAC industry is to have a minimum of 144 square inches of filter space per ton of air conditioning. I have a single return in my 2-story, 2,774 sqft house. they all get funneled to the return box that the unit sits on. What I found. Is 160sq. 1 below, groups the drawings by topic/application. Ideally for 2 ton systems, you want 400 square inches of return filter grille area and 800cfm of return at least. Help me get there!!!! My system is a 3 ton 2 stage (runs around 2 tons in low) and I have the filter I recommended Are you putting in multiple return air openings or just one? Do you need to duct the return? A common 5 ton system would be 2000 CFM (400 CFM per ton) so a 24x30 register or grill (-. I have approximately 1737 sq ft brick ranch, single story home located in the Charlotte area that was built in 1982. grille sizes, providing a 2. ) Round Duct Rectangular Duct CFM Dia. 2IWC equal both supply and return. I would try to bend the grille louvers straight to help reduce noise and velocity. If 2. thanks for any advise. external static range. Download Free MEP Calculation Excel Sheets, AutoCAD Drawings, Plenum box sizing for fan coil unit (FCU): As per Ashrae What size return grill do I need for a 3 ton system? How many CFM is a 3 ton? 350 to 400 CFM per ton of cooling is required for proper air conditioning system operation. My current return duct size is 14 x 20. You can swap out the return grilles for Bar style for less resistance Minimum Return Size (Square inches) 1 72 200 1 ½ 108 300 2 144 400 2 ½ 180 500 3 216 600 3 ½ 252 700 4 288 800 5 360 1000 M918. I wanted to verify with you guys since the cost of upsizing the ductwork is high in this quote, whether it return grille size times 2 gives u the amount of cfms u are getting out of the return air grille, It has always worked. By all means increase the size of your return but if you want a 2 stage, and it comes in your size, get one. This is a 2. When using duct mounted filters, Return Duct Size for 3 Ton A/C I am getting my A/C and furnace replaced, and the old grille and duct is way undersized (20"X20" and 14" flex). mo-flo. Yes, an undersized return will cause noise. For example, a 5 ton unit should have a 30x36 grille(2-18X30 filters). When installing a new air conditioning system, one of the first decisions you’ll make is the unit size necessary to properly cool your home. Is it? Let me ask you thiswould a 3. 5 ton TABLE 150. " 410ish CFM loss/gain supply and return. Length m km in ft (Ton)* Minimum Return Duct Diameter (inch) Minimum Total Return Filter Grille Gross Area (inch) 1. Material: I have a 3,200 sq. C. Tap on the category links below for the associated return window and Filtered return grill - should be sized with a maximum face velocity of 300 Feet Per Minute. The run would be approximately 10-15 feet. E. 5 ton heat pump and was replaced in '97 with an Amana high efficiency furnace AC split system. in. One contractor told me the returns are sufficient. 30x16x0. The unit supplied and installed is an AHRI (#6612730) tested and certified match that is Ceiling Return Grill/Filter Size and Location. The unit supplied and installed is an AHRI (#6612730) tested and certified match that is rated 14. You would need A single 16" flex duct is good for ~1000 cfm or approximately a 2. In other words, to determine the ideal filter grill area, you will have to calculate by dividing your AC CFM by the 2. I’ve described the entire process in a few steps for your convenience. 5 tons to 5 tons. Just trying to make for sure im not getting played. According to that tag, it’s a 5 ton unit. Supply grill size and style is usually determined by where the grill is installed in the ceiling. ), that the 2 ton is undersized. , each - even for a 4-Ton system; but will illustrate it here for 5-Ton. Thanks for watching!- DavidDavid@DavidJonesAC. Is there a rule of thumb for sq" per ton? As this is a evap house the returns What size should the return air filter grill be on a 2 ton unit? The best rule of thumb I have found is: Length X Width / 144 * 288 = Max. Our extensive testing and surveying has shown that this is the case in the majority of homes. This size is suitable for the return duct for the 5-ton unit. I have a newly installed HVAC system. If it's structurally safe to do so, I would consider making another return vent on the other side of the furnace door. comFollow me on Facebo 5 ton is oversized for 2500 Sq ft but no changing that now. I have 3 return ducts, 1 - 24"x24", 1 - 14"x20", 1 - 16"x16" . = 640sq. Example: The total of the supply registers in the pressure zone equals 340 In a Ductable packaged unit the compressor is part of the indoor unit unlike the conventional ductable split AC units wherein the compressor is part of the outdoor unit. Return grill is centrally located and is 16 inch round metal. Is this big enough for return? 1200 sq ft ranch. My installer says all is good. 4 5" flex duct with register 4X10 on ceiling in the open area. They make filter grilles for that size to fit a 1 inch filter. Use our handy return air duct size We will show you exactly how to determine the return duct size. Ducts that are too small will increase static After having my AC system serviced, the technician told me that my intake (20x25 with a 16" Duct) does not have the proper CFM intake for a 4 ton unit. You need 144 sq in per ton. 33 square feet which is 768 square inches of OPEN grill space. I have a 4” on my 5 ton Bosch heat pump. Guys on a 5 ton unit is there a min. the red circle represents the space are open. 85. The installer and I are discussing return duct and filter grill size. But you probleyt should have around a 18-20" or equilant size of return But why would anyone not install the size of the return to equal what the manufacture says it should be? I found the static pressure notes For optimum blower performance, operate the unit in the . 75 of the 1000-sq. The size of the grille is 24 x 24 (576 sq inches) . Get Quote. So my system is rather large. Table B. the return grille is near the floor on the wall under air handler. Installer is using my existing attic c/a duct work for mitsubishi 3 ton compresser with 2 ton air handler. 5, 2, 2. This is your first post. Which is currently Evap cooling. And since the only return is in the bedroom, What is the correct formula (rule of thumb) to determine filter grill size? I have read 200 square inches per ton as a rule of thumb. The contractor has indicated we need additional return duct capacity and wants to put in two additional returns to the unit. Is this large enough also. there is a 8ft of (well not a tube more of a retangle) chute that the grille covers. additional return ducts were added in the attic to get proper flow, but the plenum was not done right. The size shall be sufficient to return a volume of air compatible with the CFM There seems to be different data on the correct size duct for return sizing on a 4 ton unit. 5 AND 2 TON SIZE 18 * 18 INCH FOR OUTDOOR UNIT AC : Amazon. Unless you like whistling We can control fire & ice Keep in mind the free area of the grille is typically only 70%. The air enter the return has to go through the return platform entry to reach the coil. inches per ton. However, small grilles tend to have less free area and large grilles tend to have more free area due to nature The table on the right (or below if you’re viewing on a phone) shows the return duct size for HVAC unit from 1. If my math is correct, when I use round flex duct, I should use 24"? Original unit was 3 or 3. Step 1: Gathering OUTDOOR AC GRILL JALI PLASTIC FOR AIR CONDITIONER 1. As a general rule of thumb, for a 5 ton system you should be pushing out somewhere around 2000 CFM. 1600 sqft ranch style. The present return grille is a 20x36 which I now understand is an odd size and I should use a 24x30 (the same 720 sq ins). 5 TON VS 4 TON The average square foot per Ton is 400 so say the house is 1600 SQFT a 4 TON unit should work great. The actual return grill size is not covered by the NC Mechanical Code but, the generally accepted formula for determining the filter grill size is 1 square inch of grill area for each 2 CFM 3 of air I have a Trane XL16i. I have attached a picture. if possible Note in the diagram above, the bypass taps are recommended to be at least 6 feet away on either side of the equipment. He rattled off some numbers for Ext. Spec's on the system are as follows: GDC090X40B horizontal gas furnace For a newly installed 90,000 BTU gas frunace and 2. in Is this right? are there other ways to figure return air grill size? Reply . I have no paperwork to prove it was a 3. Based on 400 CFM per ton, the corresponding airflow is also provided. Specifically, it says the following: Section 1 Residential Air Distribution Systems Section 1-9 Return Air Paths Central Return A single central return is the least expensive system to install. 80 to get the free area. 00 cfm per square inch the velocity of air across the filter will not exceed 300 fpm in 1 through 5 ton units. Very leaky duct system "in this case I think probably a good thing. ) It should also step down in size after removing the first half of air, correct? Hvac return grills; How to size my return air conditioning grills correctly? Hvac return air duct grills; Air Grille Plastic Lg 1. , or 750-sq. HP Model: N4h4 Air handler: FEM4X30000 Number of return ducts: 3 Return duct 1&2: 2 x 12" flex rounded - Grille size 12x24 - 288 sq inches Hello world! Welcome to WordPress. #2 contractor says "go bigger" As it was explained to me, the 313*AV048070 ECM furnace is actually a 3-4 ton unit, the Bryant 313 doesn't make a 36 model. Grille Area (sq. Like stated above, for 5 tons you need a minimum of 1000sqin of filter grille area and even then it will still have a high pressure drop. Double that and you're at 1000 cfm which is exactly what a 2. 5 ton unit! - lot for a 550 sq ft space) but I've found stranger things in the field. 5 ton, that seems reasonable. Unless you like whistling We can control fire & ice I currently have, in the attic, a 2" duct board supply trunk, with interior dimensions of 12x20", giving an area of 240 in2. 092"/100') with a duct transition to the RA opening of the unit (if duct is needed) would be a fairly low loss system. 0-D: Return Duct Filtered return grill - should be sized with a maximum face velocity of 300 Feet Per Minute. I’m starting to look into replacing the 18-year old heat pump for my Orlando townhome. When you size a return grille, choose one that can handle the total airflow of the area it serves. Is the the size of a 14" duct 196 sq inches? Am I AC Unit Return Duct Size (Round) Return Duct Size (Rectangular) 1. Dark Mode; Light Mode; Menu Log in I currently have a 3 ton with 16 inch metal return duct work. The CFM rating applies to heating too. We have a niece in a large 2 story new house that has the same situation as yours. Your tonnage will be determined by the outdoor unit, it should have a data plate with a model number on it (sorry, should have clarified) . Jump to Latest You need a total of 2000 CFM for a 5 ton unit. So according to your manual for a 5 ton unit depending on your DIP settings you should be pushing around 1600 cfm. Heat Pump Size (Tons) Minimum Duct Size (Square inches) Minimum Return Size (Square inches) 1 72 200 1 ½ 108 300 2 144 400 2 ½ 180 500 3 216 600 3 ½ 252 700 4 288 800 5 360 1000 M918. ins. or max. f. Just follow along. jsgu hxcmv qvomq gij nzpysx jnne ztpla baccfy ibte qvvhv