American Standard 5 ton unit and Hardstart Device on generator

[jbgreig]

I have an American Standard Allegiance 12 5 ton Air Conditioner. The model number is 2A7A2060A1000AA and the date of manufacture is 01/2003.

I am trying to determine if it has a hardstart kit on it or not. Some people have told me that all ACs newer than 5 years come pre-installed with a hard start device.

I have a 16KW Generac Generator (their new model 5244) that it claims is "Central Air Certified" for a 5 ton unit. It did indeed start the unit, but it seemed to struggle a bit (lights dimmed quite a bit, took a couple of tries to get it started).

I have seen some info that a Kickstart hardstart device will allow for better starting when voltage is low and is useful when used with a generator.

I open the outside unit and found the following: A round silver GE Capacitor with the following info: 27L322 80uf 440VAC +06 .06% 50/60Hz Protected P969 T10000AFC DIELEKTROL VI 0240 D137452P39 It is about 6" long 2.5" in diameter

Not sure if this is a start capacitor or a run capacitor. The only other thing I found wired in (other than the contactor) is a gray cylinder slightly bigger than a D cell battery.

I intend to have a HVAC contractor come out and install the Kickstart device if it is of benefit, but I would rather not pay for the service charge (I live in a rural area) for someone to ome out and tell me it will do no good. Any suggestions as to what I have and whether or not the Kickstart will help? I'm kind of out of my element here.

Thanks in advance for any suggestions.

Brad

[sacstinkytiger]

Hi Brad,

I read somewhere on the internet what you want to do is to have 1.25 times the AMPACITY of the HVAC unit. .

"Sizing and Use of Generators on HVAC Units" The Comfort Zone September 2002 by Maury Tiernan

FYI our Onan RS20000 will start a 26 AMPACITY carrier HVAC unit. But I think our unit is not as large as 5 tons like yours, maybe only 1.5 tonns. I think you need to be careful because running HVAC units at below standard volts can cause extra heat, and hence possible damage. If your Genset breaker is tripping, then that may be a sign of a problem.

warmest regards, Mike.

[Oscar_Lives]

snippage>

snippage>

Brad, I think your AC has the dildo option. There was another thread here a week or so ago about these kind of AC units.

It is probably best for you not to f*ck with it any further.

[aka-SBM]

That would be.....wrong.

[Robert Gammon]

Hard start kits are NEVER installed on a new AC. The purpose of such a kit is to give extra energy to a compressor that is aging, has more internal friction.

A service call by a reputable HVAC contractor will install such a capacitor ONLY when it is needed, ie. an old unit that fails to start sometimes, particularly when the unit is hot and you attempt a restart within an hour after it shuts down.

[Geoman]

Incorrect. The reason they arent normaly installed is stricly cost. The factory trys to design a system which will allow equalization of pressures so they don't require a hard start kit to overcome starting against a high head. A cap tube, FCCV valve, a bleed txv will all allow equalization of pressures between the low and high side, that coupled with a time delay thermostat will allow the factory to save money in material and labor.

Incorrect again. Its once again cost or when needed.

On my home I have them installed, but I can't justify putting $150 on a customers unit that isn't having problems and they have the required criteria mentioned above .

I was surprised that Noons systems come with them. I was under the impression that a scroll unit equalizes when its turned off.

Rich

[Geoman]

Personally, I would not feel comfortable with the generator sized even that close. Inrush amps for starting can be up to ten times the normal amount of power required to start an air conditioner. I'm not saying to get a generator that is ten times larger than what the amperage labled on the AC, but I would at least consider a unit at least 1.5 bigger.

Also, I would make sure the unit has the proper start components, NOT THE ELECTRONIC hard start kits but a REAL relay and a REAL start capacitor that is specific to this unit. To be sure get the one from the factory who made air conditioner. I would also make sure you have a time delay start component, your thermostat may have that built in.

Rich

PS, the start relay is a black plastic and probably has a small bleed resistor across the terminals.

[Robert Gammon]

Then we are talking about two VERY different things.

I had a 1982 vintage unit on this house that was having some problems with Hot starts. We spent a night in a motel as a result. When the contractor came, he installed a second larger capacitor to give the motor additional inrush current when it started up.

This worked for a while, but when 4 adults were present in the summertime, the unit could not dissipate the heat in the house, so we HAD to escape to a mall to be comfy if son and family visited. that triggered, eventually, a complete replacement for a 12 SEER unit at $7K for AC and furnace.

[DIDO]

This capacitor is running capacitor would hard start kit help yes it would, howmuch? salid state start kits are very esey to use, it have two wires and it gets hookup accros the running cap. in addition if you can get good circutry tech. you can add small line cotactor for condenser fan and add time delay on to compressors line contactor permiting condenser fan to get up to full RPM beforr compressor cuts in this would gave you tremondus advantage on start up, condenser fan motors can drow considarable amount of power until they get up to rated RPM. good luck from Dido

[dmurphy0552]

Actually this is not correct. hard starts are installed on the better models and especially heat pumps due to their high pressure starts in winter.

[Robert Gammon]

We're talking again, about TWO very different problems.

1. Pressure differentials across the compressor that make a difficult start. This can occur on units of any size, of any age. We can agree that some mfg's on some models do provide for a hard start condition related to pressure differentials across the compressor.

1. Older compressors will have higher internal friction due to wear. Pressures in the system are nominal, exactly what they should be. These compressors may not be scroll compressors although scroll is currently a leading compressor design. A HOT start, i.e. a restart of the compressor after an extended run time, before the compressor has time to cool down, may result in a failed compressor start. Adding an extra start capacitor ONLY, will be a stop gap measure that will allow the system to run for a few more years before replacement is required. It is arguable that this is also a hard start due to a pressure differential, however the solution is far simpler and less expensive than the hard start kit that some are discussing here.

[Geoman]

We are not talking about two different things. You said they are NEVER installed unless there are problems, everyone here responded saying that you are mistaken. I went further to explain why they are not traditionally installed at the factory, which is cost. The factories will put them on some models, but not all.

Make no mistake about this, every, and I mean EVERY compressor that is single phase WILL work better and possibly last longer with a properly sized start capacitor and start relay. But to say they are only put on when there are problems is totally incorrect.

Also, your statement about the unit not cooling with four adults is possibly a different subject. If the unit started and ran and the unit would not keep up then it wasn't a hard start problem, it was most likely due to a failing compressor or the charge was off and your compressor was cooking due to no refrigerant cooling.

Rich

[Geoman]

[Colbyt]

I have a hunch that Turtle is in Orleans working his butt off and raking in the jack.

Far to busy to spend any time with us.

I do miss his style.

Colbyt

[Robert Gammon]

The coolant level was checked and was in spec. Pressures were checked and in spec. Start capacitor was checked and was within spec.

Compressor had proper start relay and start capacitor. It worked fine for 18 years. It was reaching END OF LIFE. Compressor got hot started and failed to start. Sevice tech added a extra amount of start capacitance and the unti continued to run, abeit with increasingly poor results and high expense (at the end, the monthly electricity bill more than DOUBLED over usual summertime values)

[DIDO]

Is no use talking to selfish ignorant morons I am talking to those that have brain of elephant and mine of a slug you know who you are, but if you think that you will stop me from posting you are not born yet sweet dreams from Dido

[Jake]

That was my impression as well. Help us out here, Steve?

Jake

[Noon-Air]

All 6 of the systems I have installed in the last 3 weeks, including the one today *ALL* came from the factory with scroll compressors and hard start kits installed along with factory installed filter/driers, low and high pressure switches, mufflers, 5 minute delay on break timers, and a bunch of other stuff. The model numbers on the heat pumps were (1)RPNK-024JAZ, (3)RPNK-036JAZ, (1)RPNK-048JAZ, and on the A/C condenser was (1)RAND-048JAZ. I have 2 more systems lined up for next week.

FWIW, Scrolls don't equalize pressures. Most manufacturers install hard start kits on heat pumps and a/c condensers that have a very high probability of being used on a coil that has an expansion valve on it.

[Jake]

Steve,

From Copeland's website technote on "Compliant Scrolls"...

Single Phase Starting Characteristics:

No start assist devices are ever required, even if a system uses non-bleed expansion valves. Due to the inherent design of the Compliant Scroll, the internal compression components always start unloaded even if the system pressures are not balanced.

I don't doubt that the systems you installed had hard starts...

I just want to know why?

Why wouldn't they just employ bleed TXV's and the standard anti-restart relay?

Just curious...

Jake

[Harry Cox]

Here's a clue :

Nobody gives a flying f*ck but perhaps you...

...AND...

*IF* you go off a posting with some f****ng bullshit moronic crap then whatever results you get back in return is yours alone to deal with....

Curious, has anyone mentioned "Jew haters" lately ???