Samuel Rock

Completing such a calculation has nothing to do with this thread. Marc It has every thing to do with it. As that is what is to be calculated so that you know what the load of the home is. So if the generator can handle the load that work sheet comes out to then you meet the full load requirement and don't need load shedding. However if the gen set can not put that figure out it should have load shedding installed. Sam

I am not worked up... This is just something i would like as many people to understand as possible. And given that many of you would come across this it would be a good chance for you to point it out.. but you have to take what you are looking at for face value.. If you apply other logic like "well it was not installed to run every thing" or "its only important if the city is looking for it" does not null the fact that the unit can still get overloaded. The fact when a generator is installed as a whole house system that is what it supposed to do. If it is installed with a sub panel and only set up to run selected loads then that is what it supposed to do.. If it is installed improper then a Home Inspector is supposed to tell his or her client! Sam

Marc, Look at this load calculation and tell me a 20kw generator will run this house if it looses power in the middle of winter. www.piertopier.us/hvac/general_load_cal.pdf Sam

This is how 99% of ATS get wired. this is cut from the generac manual. At this point you are switching every load in the house! Click to Enlarge 90.62 KB Sam

I just don't know how else to put this, That is why I posted in bold! There is no such thing as an emergency load only when you are transferring all circuits. I meant its right there in black and white.. If a automatic switch is installed the generator must be able to run every thing that is connected to it or have load management installed. It seams the only other people that understand this issue are people on the electrical boards and a hand full of city inspectors.. Here is what i will do let me do a load calculation sheet and show you why you can not run a all electric house on a 20kw gen set and it meet the code requirements with out installing load shedding. I wold expect you to grasp this quick Marc. I never said the generator has to put out 200A.. If your load cal calls for 150A then you need a 38kw gen set 150A*240V=36000W plus 2kw for safety. If you load call calls for 125A then you need 32kw gen set. If no house used over 100A then no one would have 200A and 400A service going to the house. A 20kw gen set is just about the right size for a house with a 100A service. If the generator you selected does not meet 702.4 "2011 code book" Full load rule then it must be the load management rule. If it does not meet nether one then it is installed in non-compliance to the code. This rule is not for the ones that know hay I cant run every thing in the house when I am on generator power.. It is for the idiots that sue McDonalds because the coffee was hot! Sam

How about this. This pdf came from the Baton Rouge Zoning and Planing Dept. It directly sites the code Article from the 2008 NEC. Download Attachment: GeneratorPermitReq.pdf 35.62 KB

The NEC only sees it two ways ARTICLE 701 Legally Required Standby Systems and ARTICLE 702 Optional Standby Systems It is not required by law as this is not a large public building, hospital, nursing home, or other critical care provider! So we know that Article 701 does not apply! So now we know that the property owner chose to install this and it is a WHOLE HOUSE APPLICATION it has a 200A Service Entrance Automatic Transfer Switch and the generator puts out 20kw that is 83A of current. The documentation from the installer states Stand-By Generator. The permit states Stand-By Generator. The manufacture says Photo of Whole Home ATS Click to Enlarge 39.06 KB Photo of Load modules that connect to the above ATS and drop off large loads. Click to Enlarge 41.77 KB Photo of Emergency loads only ATS Click to Enlarge 15.61 KB We know that article 702 covers OPTIONAL STAND-BY SYSTEMS and we know that Article 702.4 of the 2011 NFPA NEC states. So we know it transfers the whole load of the house automatically and it does not have enough power output to handle the whole load there for it must abide by the load management rule. If it does not abide by the load management rule it is installed against code! If it is installed against code the manufacture does not warranty the installation. If it is installed against code the insurance company will not insure it. In the state of Louisiana the contractor is only liable for it for a period of 12 months. So if it fails after this point he don't care! The whole reason why this was even placed in the code book was after hurricane Katerina there was so many issues with insurance companies paying for OPTIONAL STAND-BY generators that was damaged due to over loading. It was addressed and I personally sat through two seminars when reps from Generac, Kohler, Briggs & Stratton, and the insurance companies talked about the issue. They also talked about the installation of GFCI on portable generators to keep the average Joe from making a suicide connection to back feed a home. There is currently cities and parishes that follow the rules to the Tee! Unfortunately mine is not one of them! [:-censore Sam

I wish it was a bribe here, our inspectors work for the parish or for the city. They refuse to inspect for proper generator installation hell some of them just don't inspect they just sign and go! If a generator is grounded its good is how they roll! In St Mary parish we have brand new homes getting built with no AFCI, Smoke detectors, and no outdoor outlets. I can show you HVAC systems with 90%+ furnaces that have no fresh air ducted into the closet. Bathrooms with no fart fans, Kitchens with no GFCI. The list just goes on and on it just relay does, Its like the builders are still in the 80s. A lot of builders here will not hire a electrical contractor to wire a house, The pick up one of the rejects that got run out off from a electrical crew and get them to wire up the house. This still flys in St. Mary, Assumption, Terrebonne, and Lafourche parishes as the builders have licenses that are grandfathered in for this. In assumption parish they do no inspect mobile homes because the parish council says it is a burden on the poor. When the power company shows up as long as you have 4 wires running to the indoor sub panel they will snap the meter in. They do not check for proper blocking, Anchors, Sewage, or Water. I don't think it will go away any time soon in St. Mary or Assumption but Terrebonne made a big step 2 years ago and I was a big driving force behind it. Terrebonne parish no longer issues Electrical, HVAC or Plumbing licenses! You must go get a state license. So it will take a few years to fix but once the grandfathered contractors retire, shutdown, or sell out it will be a lot better. Even if the inspectors don't get better A contractor with a state issued license does better work than 99% of the ones with a local license. I think it purely due to the fact of the structured testing of your trade and business ethics/law. Most of the ones doing the shotty work would not pass the business part of the test not to mention they would not have enough capital in a company to even be able to apply for a state license. This is something I will work on for the rest of my life if need be it is only fair to the people who are purchasing the junk that most of these guys build, repair, or remodel. Sam

That compressor is a scroll, If you had looked at the first letter of the model number on the compressor it would have been a "Z" Look at you photo of the outdoor unit information tag, Do you see where it says metering device? That is telling you it has a TXV on the indoor coil and and a #61 piston on the outdoor coil Click to Enlarge 8.44 KB Click to Enlarge 8.32 KB Sam

Just in case you need it! Mod; removed link, and locked this post as I don't think we can publish the document without consent. If I've got this wrong, someone tell me and I'll unlock it.

Thanks ...................................................................... If it has a whole house transfer switch then it must service the load of the whole house! A whole house ATS comes in 200A or 100A configurations. If it has a E-Panel transfer switch it must be able to run what ever is in that E-Panel. The E-panel ATS comes with A 100A internal switchgear. If it has a 200A indoor GenReady Panel, Then the Generator must carry what ever loads are connected to the E-Panel portion of the GenReady Panel. If none of the requirements are met it is not installed to code, The manufacture recommends it be installed to code. Since the unit is in violation it has no warranty and is considered a safety issue. I would even be willing to say that if they had a 25-30kw generator that was connected to a 200A service entrance ATS and a load calculation per Article 220 I would be ecstatic about it.. If they had a 20kw generator on a 100A ATS I would be fine with it. But the fact is if you have a house that is all electric and the power goes out in the winter what will happen when you have a 20kw or smaller generator and no load management. Indoor heat strip 15kw dryer 5kw lighting load 1kw Stove 2kw water heater 4kw That is 27kw in stuff that is all used at the same time on a normal day. This is not counting pool pumps, hot tubs, any 2nd water heaters, Or all the flat screens. and the genset is already 7kw over loaded. So here is the drill, Its Christmas every one is in the house, its cold as the north pole and some puke hits a power pole and knocks it over. The sand-by comes up and trips the main at the generator that is only 80A. The customer goes outside and checks the unit and resets the breaker, Every thing starts back up and the breaker trips again. They are trying to get Christmas dinner done as the whole family is waiting! The customer goes in the shed finds a bit of wood and shoves in between the breaker handle and the ledge on the generator. This frys the power head and I get called out the following day. I find the wood, and explain to the customer why the generator burnt up. I explain to the customer that even if he had not placed the bit of wood in there that the unit had no warranty as it was installed against the NEC code and the manufactures recommendations. Customer calls me a A-Hole and refuses to pay my bill. This was my first service call I ever had for for Generac! I have been chomping at the bit to set things right ever since. That customer ended up buying a 32kw liquid cool generator as Generac would not warranty his unit that was 3 months old! The same electrician that did not install the first one properly installed the new 32kw. That customer still talks crap abut me until this very day! I was trying to avoid the epic long story and just say that the install was not to code and give the code that it did not meet. But maybe you will get a better picture of what I am trying to paint here. Every generator that is installed in St. Mary parish is installed in non compliance to NEC 702.5. I have been fighting this for 5 years now. Marc Call your local city inspection office and ask them for the generator installation permit package. The installer must do a load calculation per NEC 220 and if a 200A-SE ATS is installed and the generator does not carry the full load of the house then Load Shedding must be installed or the job will fail. Sam

Most things are R-410A now as R-22 was sent out the door a few years ago and R-134 will be replace by YF-1234 soon. R-410A has a better co-efficient for heat pumps, Some are reporting it does not due to good in desert temps when used for comfort cooling. Also scroll compressors are the norm now due to EER ratings. Other than that it is still a cooling medium going through its life cycle. The next big change we will see is Hydrocarbon and CO2 refrigerants, They are using R-600, R-600A and R-290 "N-Butane, Iso-Butane, and Propane" along with R-744 "CO2" in Europe. They have just approved R-290 for use in the states in systems that contain under 1lbs of refrigerant. We had the first run of soda machines come out last year that operate on propane! Looks like we are heading back to the basics! Sam

NEC ARTICLE 702.5 Optional Standby Systems (2) Automatic Transfer Equipment. Where automatic transfer equipment is used, an optional standby system shall comply with (2)(a) or (2)(b). (a)Full Load. The standby source shall be capable of supplying the full load that is transferred by the automatic transfer equipment. (b) Load Management. Where a system is employed that will automatically manage the connected load, the standby source shall have a capacity sufficient to supply the maximum load that will be connected by the load management system So What this says in plain English is if your service from the power company is 200A then your generator needs to be 200A; If the generator is not 200A then you need to have a load management system installed. ............................................................. I know that in my neck of the woods every generator that is installed does not have load management on it. I have been fighting to get the city inspectors to check for this since 2008 when this code went into effect. I have not come across any homes with a generator installed since I have been doing insurance inspections, But this is going to be one of my pet peeves along with the suicide backfeeds! I have been preaching this for years at community meetings and at city council meetings. I always get the same response well it cost me $1800 less to install it without load management and my electrician told me it was optional. If you get close to the big cities ie Baton Rouge, New Orleans, or Lafayette the same electrician that tells customers its optional in my back yard installs load management in his own back yard because he knows the inspectors look for it. I have taken this to state and local enforcement and no joy. I was A Generac and Briggs dealer from 2007 until 2013 and I never sold a generator in my home town because I out right refused to install it against the NCE code. I just could not live with my self if some one was hurt over me attempting to shave a few dollars off the price of a job. ............................................................. Any one have any experience with this in your market? Sam

Click to Enlarge 73.65?KB Scroll on the left and recip on the right. In short the scroll will be tall and skinny and the recip will be short and fat! You can also stop by just about any HVAC store that sells compressors and ask them for a book. You can look up the model number on top the compressor and it will tell you what it is. Copeland Scroll refrigeration compressors (such as ZRxxKA-PFV) are designated by a "Z" in the first position of the model number. Copeland Reciprocating compressors (such as CRxxKA-PFV) are designated by a "C" in the first position of the model number. The second position determines the application range (R = high/medium temperature, S = medium temperature, F = low temperature). The third and fourth positions represent the first two digits of the capacity of the compressor at its standard rating conditions and the fifth position gives the multiplier for the capacity (C = 100, K = 1,000, and M = 10,000). The sixth position designates the compressor's model generation. If there is a seventh position before the dash prior to the electrical designation, it will be an E (Polyol Ester oil) or an L (shipped less oil). If there is nothing in the seventh position, the compressor has mineral oil in it. Electrical designations (such as PFV) are the same as other Copeland? models. If the outdoor unit is frosted up you must get a snickers! once it defrost it will start again. Some heat pumps have a low temp lock out so once the outdoor temp goes below the set point it will not let the refrigeration package go into heat pump mode, but if its frozen up then that means it was just running so just let it go through the defrost cycle. If you are in a cold location then the unit should have a heater in the bottom of the compressor. Ensure the power is on at the disconnect for the outdoor unit for a few hours before you test the unit. The heater warms the oil in the compressor and keeps the refrigerant from getting dissolved into the oil. The reason you do not want the refrigerant to be dissolved into the oil is if the compressor has a oil pump when it starts pumping it will fuzz like a coke and damage the oil pump. Another thing it will do if the refrigerant is dissolved in the oil it will push all the oil out the compressor this is bad for all the rotating parts plus it oil loges the indoor coil and that is kinda a itch to get back to the outdoor unit if the tubing run is poorly designed. Sam

First of all I see no P-Trap. If this unit has negative air flow at the evaporator it must have a P-Trap to keep the sewage gas from getting sucked into the air handler. If the unit is of the Trane/American Standard make TAM7 or TAM5 then it is a positive pressure unit and does not need a P-Trap as its always pushing air down the drain. Either way it needs what is called an AirGap where it ties into the sewage line and depending on what version of the IMC your state uses you may not be able to pipe it to the vent line like that you will need to run the 3/4 line down to a drain level where the vent starts. The air gap cannot be installed by the HVAC contractor it must be installed by a plumber! The first 18ft of the condensate line must be insulated with rubbertex to keep it from sweating if its located in a unconditioned space in the home. If the unit is located in the attic it should have a drip pan below it with a emergency drain line connected to a separate AirGap from the air handler drain. The pan should also have a over flow switch to shut the unit down in the event both drains get clogged so that it don't over flow into the attic. Sam

I need more information about your install, and some photos of the outside of the house to see its basic construction would be nice. I need to know if you have a basement and if it is conditioned. If the basement is conditioned is it part of the cooling system or does it just have a dehumidifier and what is the square footage of your house. Does the house have good insulation and if possible what is the ratting of the insulation. The equipment you have is a possible match depending upon the information from the Manual J load calculation. The indoor air handler is a positive pressure unit with a computer controlled expansion valve or EEV and is rated for 30,000 BTUh the out door unit is a 36,000 BTUh but has a compressor that only puts out 32,000 BTUh. So if the unit has a lot of vertical tubing say 25 feet or more it is going to take away some BTU. Now if the unit is not preforming properly they may not have programmed it right or it may be the wrong size equipment. Sam

No Prob, I am just moving into inspections and I have been poking around here for the past day or so. I will offer all the HVAC help I can as I learn inspection from you guys and gals. Another way if you are just afraid to run the system is to turn the power off to the indoor unit. Open the thermostat and disconnect the Y wire "most of the time its yellow" and connect a Fox and Hound "this is just a toner that makes noise with a portable speaker" you can get it at lowes. put one clip on the yellow wire you disconnected and put the other on the C terminal "C stands for Cyan and a Blue wire Most of the time" then you can take you speaker and go out side and listen for the wailing sound on the small control wire going to the units. Once you locate your unit hook every thing back up. If it were me I would want to run the unit to ensure it is in operating condition. But to each his own I guess. Sam

I have been doing HVAC/R work since I was 10 years old I learned from my two uncles as a kid. I have been certified for 16 years! I am a American Standard Dealer "aka Trane" I can tell you I have ran many units in 30*F weather when we are doing maintenance. I would not sweat it at all. The issue with running a unit in the cold is if it runs to long with to low of a temp across the evaporator "The Cold Coil" you will not produce any superheat on the suction side of the system. If the refrigerant is not superheated that means it did not change from a liquid to a gas. This is real bad for older reciprocating compressors "Ie ones with pistons like a car engine" as the compressor cannot compress the liquid it will bust a reed valve or blow a hole in the piston. When a residential HVAC is shut down the suction side fills with expanded gas that has passed through the expansion device until the pressure is the same on both suction and discharge sides. As long as the line set has at least a 24" vertical rise from the air handler before going down to the condenser you have no issues with oil flooding back. So before you run the risk of flooding back the refrigerant to the compressor you must compress all the refrigerant subcool it in the condenser and pump it to the evaporator. By this time you have heard the unit run and shut it down. Also some units have controls that make the unit stack unneeded refrigerant into the condenser to reduce refrigerant flooding. If you need to run the unit for a longer time say it is only you at the location doing the inspection you can put the heater on and get the indoor temp up to 75*F to 80*F then shut the system down let the blower stage off and turn the AC on. This will give you enough time to go look at the unit and drink a cup of coffee before you need to shut it down. Remember its the air that is going across the evaporator we are concerned with! Now if you have a scroll compressor you have even less to worry about, I have seen people connect residential A/C condensers to walk-in coolers that run all winter with no safety controls and never have an issue. A scroll compressor works by having a dynamic scroll rotate inside a static scroll and does not use a piston so a small portion of liquid can be pushed through the compression stage. In fact some large scrolls have liquid injection in ordered to cool the scrolls down. If the unit is a Heat Pump you can put the unit into heat pump mode and now the out door unit will produce cold air "it becomes the evaporator" and the indoor unit will produce hot air "it will become the condenser". A heat pump has an additional component called a refrigerant accumulator this device ensures that no liquid will get to the compressor to cause damage. Heat pumps are designed to run in 20*F weather and will run until the outdoor coil freezes up then go into defrost and turn on the auxiliary heat system "ie Electric, Gas, or Oil heat" Sam