Central Air and 15kW Genset

[rgroves]

    I am in the process of finding a heat pump to install.
 

One of the things i dislike the most about this old farmhouse is the air source electric heat pump. The folks who we bought the house from installed it to replace an oil furnace.
It is an electricity hog, relies on pure resistance heat when the outside temperatures are coldest, and the air coming out of it feels barely warmer than a draft. 
I will replace it with radiant floors from a water heater this year.

Just my fwiw

Russell

[pigseye]

I like the 2 pulley idea.  Gives me something to think about.  But even with two pulleys, I'll still be spinning a 15kw gen head.  But at least the engine won't be working so hard during the non AC months.

[GuyFawkes]

or use one pulley and an epicyclic (sun and planet) gearbox for the two ratios

[pigseye]

Hi Guy,
You're talking over my head so I need to do a llittle mroe research.

On a slightly related topic, has anyone ever used a CVT to maintain rpm consistency? 

thanks,
Pigseye

[oldnslow]

I'm hunting for a souce to cannibalize a planetary gear set cheap and heavy enough to do the 2speed job direct from the crankshaft. Easier and cheapest (?) is the two pulley thing.  I am going to try this with a 10/1 at 650 and 1000rpm. My Engine and head are on the way. Still digesting the threads with BHP/Torque discussions. It's not just an RPM change but there is an increase from 1472cc in the 6/1 to 1579cc in the 10/1. Not sure how torque will be affected at 650. Not trying to hijack this thread, sorry; I like the dual pulley idea but the planetary gearset is just too cool.

[pigseye]

Hi Oldandslow,
I appreciate your comments so don't worry about hijacking.  when you say cannabilize a planetary gear set up, what would you take the gears from?  Motorcycle?

thanks,
pigseye

[oldnslow]

Hi Pigseye, don't have a definitive answer really. I was thinking more like an automatic truck/bus transmission? I think components from  motorcycle wouldn't be heavy enough to take the torque off a listeroid crank but understand where you're coming from. Never came across a (scrap) planetary gearbox "by itself" ie not built into something else.

If you look way way back to the Model T, the whole transmission was just one planetary and you pushed on pedals that worked bands to hold each part for hi/lo/reverse. Neat.  Other gearboxes would work too as would hydraulics. Alot of heavy equipment is using fluid drive these days with variable displacement axial piston pumps, etc. very cool but Expensive.

Vbelts were the right choice in the "startomatic" days. The serpentine belt seems like the logical progression from the vbelt. Still relatively cheap and effecient (enough) today IMHO. Since I plan to run my 10/1 "Ricer" at two speeds, I was looking at an alternative to "one belt/two pulleys". Just a mental excercise at this point. I just like the design of a planetary and the two-speed capability. It's more elegant a solution.

[pigseye]

Oldnslow,
It's a very interesting mental exercise.  Now that I think about it, I'm sure you are right, motorcycle would not be strong enough.

What about an auto transmission from a front wheel drive minivan?  I remember 5 to 10 years ago or so, they were putting small 4 cyuclinders in minivans and the engines were burning up and then the vans were thrown out.  I would be there are tons of front wheel drive transmissions from those old vans in scrap yards.

Is that what you're thinkings?
Pigseye

[oldnslow]

Yep, automatics are in the scrap cheap for sure. To better get a grasp on what a planetary gearset is all about try this link:
 
 http://auto.howstuffworks.com/automatic-transmission3.htm
 
Run the animation to visualize exactly what happens.  Driving the Sun gear you can hold the planet carrier and get output from the ring at 3.4:1. Drive the sun and hold the ring and you get output from the carrier at 2.4:1 in the opposite direction. Both situations you are increasing speed but at different rates and direction.

Auto transmissions were designed to reduce rpm and increase torque. We want to increase rpm to 1800 (in many cases.)
 

[pigseye]

Wow, auto trannys complicated.

thanks for the link.  It explains alot.

Pigseye