Air cooled generator operating temperature in Sub-Zero weather.

[90cummins]

Air cooled engines are designed to operate & survive in temperatures exceeding 100 deg F.
My question pertains to extended generator operation in sub-zero temperatures.
Air cooled engines would never get close to operating temperature, particularly air cooled diesels like Yanmar that are designed with large fans to ensure proper operation in high temperature environments.
Diesels generate less heat than gasoline engines particularly when operating at low loads and this could be an issue when relying on a generator in subzero conditions for extended periods.
I ask this question because I just purchased a new L70 Yanmar for my generator that has an extended capacity sump of 3 quarts with a bypass filter installed.
During the initial runs to verify operation and break it in I loaded it to 75% (3kw) and ran it for a couple hours (60 degree ambient) and the block/sump never came close to being hot enough to where you couldn't hold your hand on it.
I'm not concerned about my gasoline generators but this Yanmar is a premium unit that I'm looking to protect from adverse operating conditions. It is an open unit (not enclosed).
I'm thinking an insulated enclosure (for noise and temperature control) that has a thermostatically controlled cooling fan to allow the interior to warm up to an acceptable temperature of 70 to 90 degrees.
This engine is equipped with a low oil pressure shut down system and I could easily add an oil & air over temperature shutdown also.
Any input??

90cummins

 

[3930dave]

That sounds like a workable strategy (dedicated enclosure), provided you account for max Summer operation.

That said, I'd verify what ambient temperature the L70 is rated for by Yanmar, w/o an enclosure. I've never contacted their technical support, but I wouldn't be surprised if you were to get detailed feedback from them concerning low temperature operation w/o a "heating" enclosure - they may already have detailed specs on this, including Min. Low Ambient vs. Rated Load.

Rgds, D.

 

[oldnslo]

Interesting thought, my uncle had two of the air cooled Deutz tractors and used them all year around for hauling manure, grinding feed, etc. in central Minnesota with no problems. These didn't run unattended for extended periods of time though either. I do not know if these had some type of temperature operated gate on the cooling fan or not. The fan itself was belt driven so it ran all the time.

 

[Industrial Toys]

Some friends of mine had a genset, maybe 6.5 KVA from Northern. It was a 3600 RPM job with a crappy generator end. It had a Yanmar single cylinder Diesel, air cooled. Although I am not a fan in any way shape or form of 3600 gensets for emergency standby use, I do very much like Yanmar. Anyway, the set was installed in a dog house with plenty of screening. The exhaust was piped outside.

After only 20 hours or so, the generator end was fried. We don't know what happened. Possibly the exhaust pipe came off as it had only been slid on. What I found remarkable, and is the point of my story, is that while servicing the machine, after replacing the generaor end, I found the foam in the air cleaner melted in spots. That thing must have sucked some real heat! The engine still works fine, it seems.

 

[s219]

You could put a set of auto-control louvers on any enclosure you build, and set them to open at a desired temperature. Greenhouses use them. That would give you the capability to have the enclosure sealed tight in cold weather, but automatically vent as things warmed up.

I have a water cooled diesel (Isuzu 4-cyl engine) and have large vents built into the small 4x8 shed that encloses it. One vent is lined up with the radiator (which pushes air out) and the other is in an opposite corner to serve as an intake. In the event I need to run in very cold weather, I'd simply keep the vents covered up until things got to operating temperature.

 

[90cummins]

I could not find any information pertaining to the detrimental effects of excessive heat or cold, the following quote is all I could find.
(Air temperature affects generator output. Output drops 1% for each 10° temperature rise above 60° F. Very low temperatures may make the engine hard to start. See engine owner’s manual for more information.)

90cummins

 

[Industrial Toys]

Actually, REAL gensets give temp rise in their specs. Others don't even know what they are talking about!

 

[Agvg]

Interesting thought, my uncle had two of the air cooled Deutz tractors and used them all year around for hauling manure, grinding feed, etc. in central Minnesota with no problems. These didn't run unattended for extended

In extreme cold I think they prefers air cooled diesels, nothing that freezes is a big plus.

 

[3930dave]

I could not find any information pertaining to the detrimental effects of excessive heat or cold, the following quote is all I could find.
(Air temperature affects generator output. Output drops 1% for each 10° temperature rise above 60° F. Very low temperatures may make the engine hard to start. See engine owner’s manual for more information.)

90cummins

Starting, Fuel, Oil. Assuming Starting and Fuel (heated filter option ?) are OK, then the only real issue I can see for Cold operation is condensation in the oil. Synthetic assumed for low Temp.

If you can't talk with a factory field applications engineer, then it comes down to Try it and See. Even with gas engined cars, some are much more prone to crankcase condensation than others.

Rgds, D.

 

[Industrial Toys]

I bought a Deutz 3 cyl for my loader mounted snowblower. Havn't finished that project yet, but I got some heater, that burns diesel within the cooling chambers of the motor, since you can't have a coolant heater. I am curious to try it some day, but just thought I might mention it as being quite different.