Kw rating4-ton tempstar


  #1  
Old 09-12-08, 06:20 PM
S
Member
Thread Starter
Join Date: Sep 2008
Posts: 5
Upvotes: 0
Received 0 Upvotes on 0 Posts
Kw rating4-ton tempstar

I need to install a stand-by whole house generator for elderly parents home who live in Gulf Coast of Mississippi.

I need to get a general idea of what the KW demand for a 4-ton tempstar. The unit is 5 years old and I can't read the spec plate.

Any general ideas from professionals
 
  #2  
Old 09-13-08, 05:02 AM
M
Member
Join Date: Jan 2008
Location: Tennessee
Posts: 438
Upvotes: 0
Received 0 Upvotes on 0 Posts
Air Conditioning Repair

The information plate won't help you anyway as you can install various heat kits in a unit so you will need to look at the heat kit itself but you are probably looking at somewhere either side of 15 kw.
 
  #3  
Old 09-13-08, 10:59 AM
Jarredsdad's Avatar
Member
Join Date: Oct 2002
Location: Troy, VA
Posts: 1,392
Upvotes: 0
Received 0 Upvotes on 0 Posts
I don't think I would worry about A/C if the power was out. More, refrig, lights, tv. And here, my well pump.

But, that's Me and doesn't answer your question.

What you'll need is a volt/ohm meter and an amp meter.

For each elec appliance you expect to run on the generator you'll need voltage and amperage readings.

Amps X Volts = Watts.

So if I have a 208/230 volt A/C rated at 20 amps (just picking numbers), I'm looking at 4160 and 4600 Watts respectfully.

Using real world numbers, say the unit is found to have 221 volts supplied and actually draws 13.2 amps in steady state operation (after say 10 min run time). This is 2917 Watts or 3 Kw, add a little fudge every time.

To make it even more tricky, you also have to worry about Inrush, or the starting amps when the unit turns on.

Using the above example, with 221 volts supplied, say when the units contactor first pulls in the amps spike to (pick) 39.7 amps. That's 8773.7 or 9 Kw just to get the thing running.

You will need a generator that can handle that sudden spike and provide the current to get it running. And that's just the outdoor unit.

As Mike pointed out you could have 5, 7.5, 10, 15, or even 20Kw heat strips in the airhandler.

You need to decide what you want to run off of the generator. Add all Kw's up, add a few helpings of fudge and go from there.

Maybe easier to find a standby generator company to evaluate if you truly want to run the entire house on a generator.
 
  #4  
Old 09-13-08, 05:37 PM
S
Member
Thread Starter
Join Date: Sep 2008
Posts: 5
Upvotes: 0
Received 0 Upvotes on 0 Posts
Why A/C is important

Elderly parents and scorching heat with saturating humidity during hurricane season along with medical equipment. If it were just a few hours or a day with out electricity I would just use a 12,000 btu & maybe 6000 kw portable. Unfortunatly these storms can cause so much damage to infrastructure it can be weeks w/out power. Gasoline often is unobtainable and large quantities are difficult to store and maintain.

Additionally, their home has never lost access to natural gas during even the worst storm so that fuel appears to be the best alternative and most dependable.
 
  #5  
Old 09-14-08, 06:29 AM
G
Member
Join Date: Dec 2006
Location: south carolina usa
Posts: 165
Upvotes: 0
Received 0 Upvotes on 0 Posts
Due to age and physical considerations, You may be interested in this site.
http://www.briggsandstratton.com/eng...rator_systems/
These units are available in diesel and Have automatic transfer switches built in. They will have approx 20% standby capability which will tackle your motor starting loads.
Your parents would only notice a blink before power was restored.
This may be more pricey than you cared to spend, but would offer ultimate protection for them.
 
  #6  
Old 09-14-08, 10:57 AM
G
Member
Join Date: Dec 2006
Location: south carolina usa
Posts: 165
Upvotes: 0
Received 0 Upvotes on 0 Posts
The following site will give step by step instructions on selecting the gen to meet your individual needs.
http://www.homegeneratorsystems.com/buying_guide/se
 
  #7  
Old 09-18-08, 06:34 PM
S
Member
Thread Starter
Join Date: Sep 2008
Posts: 5
Upvotes: 0
Received 0 Upvotes on 0 Posts
Well done

Thank you, It should have been so obvious
 
  #8  
Old 09-18-08, 07:06 PM
Jarredsdad's Avatar
Member
Join Date: Oct 2002
Location: Troy, VA
Posts: 1,392
Upvotes: 0
Received 0 Upvotes on 0 Posts
Sometimes yes, sometimes no.

Here you have a bunch of brothers and sisters to offer opinions and input to help make the best decision You can make.

Be strong, go forward.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: