Home Standby Generator

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Julie, just checked with the gas company. They say 220 cf/hr ( which is what my spec's call for ) is not a problem. They just have to change the gas meter. Steve...
 
Ragin Cajun said:
It's been 7 years since I installed it and I don't remember. When I get back to the office (and remember!) I will see if I can find the data.
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Thanks -- that would be useful information to keep stuffed in my head. I hang out in places with very unreliable electrical power in my spare time.

At the very least, you need to get with a mechanical engineer who is familiar with the issues, that's what I did. 225CFM is a LOT of gas.
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Yeah, after clicking the "Submit Reply" button about it I realized how much air that is. In small block V8 terms it's less than 1/3rd of W.O.T. for my car ... which is why it didn't seem like all that much at first. It also makes me wonder just how practical something like that is in a typical residential environment. Harkens back to the discussion about tankless water heaters and their 150A or so appetite for electricity ...
 
sparkync said:
Julie, just checked with the gas company. They say 220 cf/hr ( which is what my spec's call for ) is not a problem. They just have to change the gas meter. Steve...
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Thanks -- and I just re-checked Generac's website. It's 220 cubic feet per HOUR. D'oh!

Urph. Bad Julie, no biscuit ...
 
sparkync said:
Julie, just checked with the gas company. They say 220 cf/hr ( which is what my spec's call for ) is not a problem. They just have to change the gas meter. Steve...
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Does that mean the gas pressure after the regulator and meter are higher than the original? What size line will you need? How far from the meter is the generator? At low pressures, line size and length vs flow are critical.

RC
 
Ragin Cajun said:
It's been 7 years since I installed it and I don't remember. When I get back to the office (and remember!) I will see if I can find the data.

At the very least, you need to get with a mechanical engineer who is familiar with the issues, that's what I did. 225CFM is a LOT of gas.
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I looked into this one time. It seems that the low pressure regulator supplied to most residences will not allow adequate flow for this type of generator. I was told one would probably have to add a regulator just for the generator.
 
Rajin, just check with generator supplier. The solinoids and time delay are built into the unit I'm planning on getting. Thanks.. Steve. Only other problem I see now is trying to get the water heater and a/c unit into the inside panel so I can tie them into the TS.
 
sparkync said:
Rajin, just check with generator supplier. The solinoids and time delay are built into the unit I'm planning on getting. Thanks.. Steve.
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Well, I'm glad to see it's now "included." Wonder if a "poof" brought that about?

Don't know where in the country you live, but I assume you have gas heat so you want to be sure the AHU is on the gen as well.

RC

RC
 
sparkync said:
I was told that there would be a bigger meter installed for the generator and a regulator installed for the furnace. Steve
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I was told my meter was adequate, but the regulator was not. The guy suggested the cheapest solution was to add another regulator downstream of the meter before the existing regulator.

I also was told by someone else that the gas company will not allow a residential installation to have two regulators.

Who knows what the real story is.
 
kbsparky said:
One way to include a water heater on a standby system is configure it for 120 Volts when operating on the generator. That way, you will be heating the water, but at a slower rate, saving valuable capacity for starting loads such the A/C, fridge, freezer, water pump, etc.

A simple DPDT relay can accomplish this task.
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Are you saying that if you run 120V through a 240V element it will work at a slower rate but still heat the water? Wouldn't the amperage increase at the lower voltage?
 
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m73214 said:
Are you saying that if you run 120V through a 240V element it will work at a slower rate but still heat the water? Wouldn't the amperage increase at the lower voltage?
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Don't forget, W = V^2/R, Since the resistance is constant, if you half the voltage, 1/4 the power. Now an inductive load, that's not a constant impedance. Lower the voltage and the current will increase until you burn it up.
 
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