Trying a new idea for the exhaust on my 802a

[Summerpaws]

Someone mentioned my lack of an exhaust system on my last post. It was a valid point. Carbon monoxide is nothing to joke about. I had plumbed an 1 1/4 black iron pipe from the generator, out the side of my enclosure. I removed the pipe when I took off the covers for my testing. I did not have a flexible pipe in it and I was going to fit one. Being an engineer, and one that thinks outside the box, I wondered if there was a better way. What if I could construct a system that didn't need a flexible pipe? In the power plant where I worked, we had many gas fired boilers and other equipment. The big ones had a hard ducted exhaust but the smaller ones used a venturi system. I even had one for my motorhome's generator for when we were parked near other campers and had to run the generator. The principal is simple. Hot gasses introduced into a larger diameter vertical pipe will cause low pressure to draw cool ambient air in thus cooling the pipe and accelerate the flow. I decided to try it. My whole system is made from 4 inch duct from Home Depot. I bought a dryer vent for the termination and a venturi hat for a gas water heater for the intake. I used the 1 1/4 coupling and an 8 inch nipple screwed to the generators muffler. I suspended the ducting to the rafters. The pipe from the generator does not touch the ducting. I ran the generator under load for 1/2 an hour and, although hot, I was still able to rest my hand on the ducting. There was no exhaust smell in the enclosure. I did not have a way to test the airflow with smoke, but using a long stemmed lighter I noticed the air being drawn into the intake side of the duct from almost 6 inches away. Total cost was under $50. I am planning on doing a multi hour run in the next week or so and I will monitor the duct temps where the termination is screwed to the fence. I can easily fabricate an air gap there if needed but I don't think it will get anywhere close to the combustion temp of the wood. (Anywhere for 300 degrees F to 600 degrees).

 

[Scoobyshep]

That would do it. Cheap insurance here would be having a co monitor in the house.

Sent from my SM-S908U using Tapatalk

 

[Summerpaws]

That would do it. Cheap insurance here would be having a co monitor in the house.

Sent from my SM-S908U using Tapatalk

I have 5. One in the basement and 2 on each floor. All hardwired together. Can't be too careful.

 

[2Pbfeet]

Someone mentioned my lack of an exhaust system on my last post. It was a valid point. Carbon monoxide is nothing to joke about. I had plumbed an 1 1/4 black iron pipe from the generator, out the side of my enclosure. I removed the pipe when I took off the covers for my testing. I did not have a flexible pipe in it and I was going to fit one. Being an engineer, and one that thinks outside the box, I wondered if there was a better way. What if I could construct a system that didn't need a flexible pipe? In the power plant where I worked, we had many gas fired boilers and other equipment. The big ones had a hard ducted exhaust but the smaller ones used a venturi system. I even had one for my motorhome's generator for when we were parked near other campers and had to run the generator. The principal is simple. Hot gasses introduced into a larger diameter vertical pipe will cause low pressure to draw cool ambient air in thus cooling the pipe and accelerate the flow. I decided to try it. My whole system is made from 4 inch duct from Home Depot. I bought a dryer vent for the termination and a venturi hat for a gas water heater for the intake. I used the 1 1/4 coupling and an 8 inch nipple screwed to the generators muffler. I suspended the ducting to the rafters. The pipe from the generator does not touch the ducting. I ran the generator under load for 1/2 an hour and, although hot, I was still able to rest my hand on the ducting. There was no exhaust smell in the enclosure. I did not have a way to test the airflow with smoke, but using a long stemmed lighter I noticed the air being drawn into the intake side of the duct from almost 6 inches away. Total cost was under $50. I am planning on doing a multi hour run in the next week or so and I will monitor the duct temps where the termination is screwed to the fence. I can easily fabricate an air gap there if needed but I don't think it will get anywhere close to the combustion temp of the wood. (Anywhere for 300 degrees F to 600 degrees).

Nice job on the custom Venturi exhaust!

If it were me, I would think about an air gap at the fence, since the fence is connected to the house via the rafters. (It's fire season out here, so we tend to see fire risks. Hammer/nail issue.) It might never happen, but I tend toward the view that during a grid outage, there may be other things going on that might distract me from the generator at times.

All the best, 2PbFeet