Onan Generator Heat

[sportsman_500]

On my Raptor 3612 the generator compartment is designed probably like every other one out there. Over the weekend we were running the genny almost non-stop. On Friday night I was checking a few things and noticed the generator compartment door was very hot to the point where you almost could not touch it. When I opened the door I found that the inside liner had deformed from the heat and on the lower right hand corner of the generator there is a horseshoe shaped opening. Super hot air was blasting out of that opening onto the inside of the compartment door. Has anyone else experienced this? Is that hole on the right lower supposed to be blocked off? or is it part of the generator cooling system?





Edited Images to fit the page.

[hvac]

I had just changed oil. Real easy. Oil filter was very tight from factory. Used onan filter and filter cap to socket. Recommend it as not much to grab on to.

[hvac]

Muffler and air flow.

[hvac]

Drain and oil filter access

[hvac]

This is how ATC does it.

[Onan]

Those vents are what we call 'mouseholes'. They are used as tailpipe exits for installations mounted in a flat bottom compartment/box. If your generator 's mount does not have a 'floor' underneath it these holes may not need to be covered. However, there is no downside to covering them. In certain installs they can cause heavy recirculation of the hot air.

Bottom line, cover them, it may gain you a few degrees of cooling.

[Y-Guy]

I'd agree but I think it really depends on the install in the RV. My guess is that some block the bottom venting and thus need more front/read venting. But I'm no expert and I didn't stay in a Holiday Inn Express either. 😛

[lincster]

So I have my trailer home today doing some stuff.
Ran genny for a while.
I held a kleenex up to that hole that everyone is saying to cover with tape. Kleenex barely moves.
I took my thermal gun across my door, side ways, temp variance of about 5F.

Take it for what it's worth, but I don't think adding that tape does a whole lot.
I still think how the OPs is mounted is the majority of the issue.
But maybe it is the door material?

[ford_truck_guy]

I get to the tracks at noon on Friday, start the generator and run it to Sunday, or Monday depending on which day the race is.. No issues here..

[dedmiston]

The longest I ever ran mine was 60 hours straight, in triple digits. I was chaperoning one of my kids, volunteering to sweep up trash with a high school group at NASCAR in Fontana over Labor Day weekend.

I had to drive out to buy more gas, but I never shut it down and never turned off the A.C.

Everyone hated that weekend and the school didn't return again. I think NASCAR even moved the event to another time of year.

[hvac]

dannko wrote:

hvac wrote:
Our ATC 28 front bedroom has same size 5.5 mounted on the tongue. They enclosed it with a metal cover but its not internal to the coach. So far no issues.

This is one FEATURE I really like. No worries whatsoever about exhaust and heat. Though even like a conventional rv I was thinking if I get an ATC I would add a radiator fan somewhere in the box to aid in airflow. In Texas on 100 degree days, more air movement is needed.

HVAC how about inside noise, do you think it's less than a coach mounted generator?

We did run it for 5 hrs in outdoor temps in mid 90s and no issues. The 5.5 is a smooth running twin, and the mounting alongside the integrity of the coach really isolates the unit. Its impressive how well it all comes together. Not sure a fan is needed. Possibly heavier weight oil if in continuous extreme heat.

[wing-shooter]

We have a 2017 onan in TH 5th wheel and we had upper 90's this weekend. It was running so hot the floor inside above it was hot. I opened the compartment door about 2 inches and that seemed to help I do not have the tape on the front either.

Should I expect it to run cooler in hot temps? First built in for me.

[lincster]

Very odd about the tape.



This is how my genny has looked since the day I bought it 12 years ago.
Never an issue with heat.

[sportsman_500]

y-guy wrote:
The area that is tapes off is the air outlet, so without that tape the hot air is being pushed to the door. Get some heat tape and recover it.

Yep. Onan tech support told me the same thing after looking at that diagram. Thanks for the info. It is taped off and I ran the genny over the weekend without any issues.

[Y-Guy]

The area that is tapes off is the air outlet, so without that tape the hot air is being pushed to the door. Get some heat tape and recover it.