View Single Post
  #15   Report Post  
Posted to rec.crafts.metalworking,alt.home.repair
Pete C. Pete C. is offline
external usenet poster
 
Posts: 6,746
Default Generators, nat gas: Noise?


"Bruce L. Bergman (munged human readable)" wrote:


trim

I'm thinking of keeping mine inside (theft, consideration of neighbors) --

Inside is a bad idea unless you build it into a sealed externally vented
space with CO detectors adjacent.


This was discussed here a couple months ago. Someone
posted the requirements for indoor generators for their
location, ie fireproofing, venting, detection, etc and it was so
tough that for all practical purposes
you could forget about it for a typical residential application.
Don't know what other locations codes are, but I'd
suspect it isn't going to be easy. But before going down
the in-house road, I would check the local codes.


If you want to see for yourself, call your local Phone Company and
go get a tour of their generator room, that one has to meet the local
building codes. It's complicated, but not beyond a resourceful RCM'er
to set up.

It's in a fireproof room (5/8" 2-hour Drywall) with 2-Hour rated doors
and automatic closers, etc - Just like your garage at home.

They have large vent grilles on the exterior wall, low and high, for
cross ventilation. Just like your garage at home, but bigger and
there are exhaust fans to make sure.

There is usually an exterior door so the Firemen have a way in without
letting the fire into the building, Just like...

There is an exhaust pipe leading outside to get rid of it up high - on
the wall or roof, away from other air intakes. Just like... if you
installed an exhaust hose system to work on your cars inside in the
winter.

There are fire sprinklers, just like you can install in a house if you
choose to - and they're starting to require them in new homes.

And several fire extinguishers rated for the use and sized for the
fuel load, and all the people working there get periodic live-fire
training to use them effectively. You can get your local Fire Station
to teach your family and friends the basics, then they hand you a
charged extinguisher, light off a quart of gasoline in a steel pan,
and say "Here, your turn!" and you find out how to do it for real.

The fuel source is piped in remotely to a 5 or 10 Gallon Day Tank next
to the generator, and a bare minimum of other flammables are stored in
that room, so a fire in the generator goes "Pfft!" and out - it
doesn't have a lot of fuel to take out the whole house. You do the
same thing, the Gasoline cans are in a separate "Flammables" locker
either outside (I have a steel shed) or clear on the other end of the
garage.

They have a way to route cooling air straight into the radiator and/or
a way to route hot cooling air out. Or they have the radiator remote
mounted on the roof.


Most of our DCs have the generators outside the building in a separate
area surrounded by high concrete walls and open at the top for
ventilation in addition to large louvered panels on the walls. Fuel
(diesel) is in separate underground tanks or above ground CONVAULTs.
Some of the city DCs do have in basement or on roof generators, but
where there is room the separate building / enclosure is less expensive.


is it generally straightforward to hose-clamp a metal flex hose to a
tailpipe? IS there a tailpipe on the small units to clamp to?

Go look at the display unit in any 'Depot or Lowe's. I believe there is
a stub of tailpipe sticking out of the housing.


The ones I've looked at have an oval flange with two screws holding
the USFS Approved Spark Screen over the exhaust outlet - making a
flange that fits or getting a spare from the maker, then adapting it
to connect flexible metal exhaust hose to a rigid exhaust pipe headed
(up or out) is your RCM Skills Test.


It's usually a dual setup, and the hole in the middle of the oval flange
is usually an NPT thread, 3/4" or 1" usually.


Any experience with these types of units, brands? Recommendations?

The home standby units are intended for just that, home standby. They
are not remotely close in construction to the commercial grade units
even in the sizes where the residential and commercial models overlap in
rated capacity. They will do the job, but will not last through very
many long outages, especially if loaded near capacity. If they are sized
to run perhaps half load, are well maintained and typical outages are
only a few hours duration they are fine. If you are in a rural area and
days long outages are common invest in a commercial grade unit.


A neighbor here had a $7K Generac that was about 5 years old. It ran
for 4 hours during the hurricane in August, then quit. Company that
installed it told him it was shot and not worth fixing.


Company that installed it should have their butts sued off for
forgetting to put in the motor oil...

Even the cheapest should be good for 1,000 to 2,500 hours if treated
halfway decent.


Agreed. If it only ran 4hr, it had not been maintained properly, or had
an awful lot of run time in those 5 years.


If I were looking for emergency power, I'd go with one of the
portable units. There are some that are available that run on
nat gas. Or there are kits available to make most of them into
either permanent nat gas or even tri-fuel units that can use
gasoline, nat gas, or propane. One of those together with
an inlet and lockout breaker arrangement from Interlockit
is what I would use. You can have the inlet installed outside,
nat gas line available and just move the generator there
when needed. And if that generator fails, you can buy a
whole new one for a fraction of the price of the standby
units. The generator is also available for other use if
needed. I could put the above together for $1000



A portable tri-fuel generator with a outdoor inlet connection to an
interlock kit, and a nat. gas quick connect with shutoff valve at the
outdoor location is an excellent option for a technically competent
homeowner. The tri-fuel gives an extra level of backup in the somewhat
unusual but not unheard of event of gas service interruption at the same
time as power interruption.

A permanently installed standby unit with automatic exerciser and
automatic transfer switch is still a better option for a non technically
competent homeowner, particularly for cases where there is life support
equipment needed by a resident (should have a UPS as well).


You do get what you pay for. If I was going through that much trouble
to install it in a house, I'd be looking for a fairly recent
Commercial model permanent mount diesel plant.

The Contractor model portables are built down to a price, not up to a
service specification they have to meet or exceed. Sometimes you can
get a good deal on a refurbished Commercial unit for a song.


With the hinky economy I bet you could get a good deal on a used top
grade (Multiquip WhisperWatt, Agrecko (sP?) etc.) towable silenced
diesel generator that you have to look at the meters on to tell if it's
running (yes, they are that quiet).