allseason Posted January 31, 2012 Report Posted January 31, 2012 I inspected a house last Thursday, outdoor temps around 20-30 degrees. Unable to test A/C systems due to cold. Today the buyer says wants to run the units tomorrow, temps today in northern NJ around 50-55. Tomorrow will be the same. The seller has given permission to test the systems. Will there be any risk to damaging the comp/cond units or foaming the oil? Still seems too cool out. My feeling has been over 60 for at least three days.
Nolan Kienitz Posted January 31, 2012 Report Posted January 31, 2012 My local HVAC guys and manufacturers have always "strongly suggested" not running them when ambient air temp is below 60-degrees. If it were me I would "not" be running them.
Neal Lewis Posted January 31, 2012 Report Posted January 31, 2012 Why three days? The A/C at my house has been operated at temperatures under 50 degrees several times without any problem, so far. Scroll compressor.
hausdok Posted January 31, 2012 Report Posted January 31, 2012 I'd refuse to do it. If you go out there, run the system and it breaks down immediately or even later on they'll blame you and say you should have known better. Have the client insist that the seller call an HVAC tech to see if an HVAC tech is willing to do it. If an HVAC tech is willing to do it and screws it up he'll be the one holding the bag, not you. There isn't enough margin in this business to risk wiping out all of the profit from an inspection by doing something foolhardy just to be the nice guy. ONE TEAM - ONE FIGHT!!! Mike
allseason Posted January 31, 2012 Author Report Posted January 31, 2012 I'd refuse to do it. If you go out there, run the system and it breaks down immediately or even later on they'll blame you and say you should have known better. Have the client insist that the seller call an HVAC tech to see if an HVAC tech is willing to do it. If an HVAC tech is willing to do it and screws it up he'll be the one holding the bag, not you. There isn't enough margin in this business to risk wiping out all of the profit from an inspection by doing something foolhardy just to be the nice guy. ONE TEAM - ONE FIGHT!!! Mike Well said, I agree. What I have heard locally is not to run the system unless there has been three or more days of temps 60-65.
Bill Kibbel Posted January 31, 2012 Report Posted January 31, 2012 If it's a scroll compressor, I wouldn't be concerned. If it's piston, I would not operate it unless above 6o degrees or at/above the manufacturers warning. Some manufacturers state 65 degrees.
Marc Posted January 31, 2012 Report Posted January 31, 2012 I inspected a house last Thursday, outdoor temps around 20-30 degrees. Unable to test A/C systems due to cold. Today the buyer says wants to run the units tomorrow, temps today in northern NJ around 50-55. Tomorrow will be the same. The seller has given permission to test the systems. Will there be any risk to damaging the comp/cond units or foaming the oil? Still seems too cool out. My feeling has been over 60 for at least three days. You bet there's danger there. At those temperatures, liquid refrigerant might well end up at the compressor suction where it can damage the reed valves in the compressor because there's not enough heat to evaporate all of it at the evaporator coil. The liquid exits the condenser at a much lower temp in winter than summer. Compressors are intended for gases only. I don't test under 60 degrees ambient. I ain't buying someone a new compressor. As for Scrolls, Bill may be right but I wouldn't risk it. Why test in the winter? It's not a valid test since winter ambient temps are far outside the design values. Marc
allseason Posted January 31, 2012 Author Report Posted January 31, 2012 I've already let them know that I am not willing to take the chance and used Mike's recommendation that the seller can make good. The buyer wanted me to put in the need for a $10k escrow to cover the three units if they should fail (installed 2002) to provide adequate cooling when needed. I told them that that is the attorney's job. They informed me that the attorney told them to tell me to put that in the final report. I said no.
hausdok Posted February 1, 2012 Report Posted February 1, 2012 I've already let them know that I am not willing to take the chance and used Mike's recommendation that the seller can make good. The buyer wanted me to put in the need for a $10k escrow to cover the three units if they should fail (installed 2002) to provide adequate cooling when needed. I told them that that is the attorney's job. They informed me that the attorney told them to tell me to put that in the final report. I said no. I'm glad you told them no. I won't test AC systems under 60?F and when temps are that low I exclude any AC system in writing in the report. Why would I then want to somehow enmesh myself in the negotiating end of the transaction by putting something in my report that says they should put money in escrow when I don't give a rat's ass who pays for what when once I've completed my inspection? It seems that real estate professionals, banks, insurance companies and attorneys are constantly trying to define our responsibilities for us and are abdicating their own. If they want you to do the attorney's job, tell 'em that you'll have to use the attorney's billing scheme and make sure you charge them for that phone call. ONE TEAM - ONE FIGHT!!! Mike
John Dirks Jr Posted February 1, 2012 Report Posted February 1, 2012 How does one distinguish between a scroll and piston compressor?
Marc Posted February 1, 2012 Report Posted February 1, 2012 If you can't see any markings that identify it as scroll, take a look at the compressor. Scrolls are taller and slimmer like nephews and nieces, piston units are short and fat, like in-laws. Marc
John Dirks Jr Posted February 1, 2012 Report Posted February 1, 2012 If you can't see any markings that identify it as scroll, take a look at the compressor. Scrolls are taller and slimmer like nephews and nieces, piston units are short and fat, like in-laws. Marc Hehehe...I can relate to that.
Tim Maxwell Posted February 1, 2012 Report Posted February 1, 2012 If you were to run it and something goes wrong I bet your E & O will not protect you...... I just say no almost all winter long. Most buyers understand it once you explain it to them.
hausdok Posted February 1, 2012 Report Posted February 1, 2012 We made it real simple here: WAC 308-408C-130(2)(e) Air conditioning systems The inspector is not required to operate cooling system components if the exterior temperature is below sixty degrees Fahrenheit or when other circumstances are not conducive to safe operation or when doing so might damage the equipment. ONE TEAM - ONE FIGHT!!! Mike
Charlie R Posted February 2, 2012 Report Posted February 2, 2012 What do you do with a heat pump, same rule? Don't run in cooling mode under 60-65, what about a limit for running in the heat mode?
Marc Posted February 2, 2012 Report Posted February 2, 2012 What do you do with a heat pump, same rule? Don't run in cooling mode under 60-65, what about a limit for running in the heat mode? Test it in heat mode if it's the winter season, in cool mode if it's summer. If ambient temps are 60 to 65, test it in either mode. Marc
Scottpat Posted February 2, 2012 Report Posted February 2, 2012 If you were to run it and something goes wrong I bet your E & O will not protect you...... I just say no almost all winter long. Most buyers understand it once you explain it to them. Correct, E&O would not cover it. But, your GL insurance would kick in for the coverage. G&L takes care of things you break and E&O takes care of the things you miss or your client thinks you missed!
Charlie R Posted February 2, 2012 Report Posted February 2, 2012 Thanks Marc, that's pretty much what I do, I was just curious if there is a specific temperature above which manufacturers recommend you don't use the heat mode, and why.
Tim Maxwell Posted February 3, 2012 Report Posted February 3, 2012 If you were to run it and something goes wrong I bet your E & O will not protect you...... I just say no almost all winter long. Most buyers understand it once you explain it to them. Correct, E&O would not cover it. But, your GL insurance would kick in for the coverage. G&L takes care of things you break and E&O takes care of the things you miss or your client thinks you missed! Right, I had that wrong. But what I was thinking is that the GL may not cover it if they were to investigate a little and found out you ran the system when you were not supposed to.
HVACMASTER Posted March 15, 2012 Report Posted March 15, 2012 Im curious, how do you guys "check" ac units? A good tech can test ac as low as 55 ambient using superheat and subcooling methods and i prefer digital gauges, while monitoring refrigerant state. But units shouldnt be operated "normally" or for extended periodsnof time below 60 ambient to avoid liquid slugging
Marc Posted March 15, 2012 Report Posted March 15, 2012 Im curious, how do you guys "check" ac units? A good tech can test ac as low as 55 ambient using superheat and subcooling methods and i prefer digital gauges, while monitoring refrigerant state. But units shouldnt be operated "normally" or for extended periodsnof time below 60 ambient to avoid liquid slugging Home inspectors generally don't connect gauges to the refrigerant system. If something happens such as a valve stem starts leaking, we're not equipped to fix it. Marc
Denray Posted March 19, 2012 Report Posted March 19, 2012 What is the problem with running a HP in heat mode in the summer?
Marc Posted March 20, 2012 Report Posted March 20, 2012 What is the problem with running a HP in heat mode in the summer? High head temperatures. It burns the valves. Marc
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