A quick question aimed to those that might know. I am doing an install of a Snugger Diesel heater, and I am mounting it under the floor of the van. Now the instructions say that the maximum length of the exhaust pipe is 2 meters, and my reasoning for that is that the supplied exhaust tubing is corrugated, and a length longer than that would develop too much back pressure.
I have a few lengths of 25mm stainless tube left over from my boating days, and have a TIG welder at work, and am going to make up an exhaust pipe which will be smooth inside. I am thinking about directing the exhaust out at the front of the van as there are no opening windows there, the exhaust fumes will be well away from others, however the pipe length will be between 3.6 and 4 meters. Would it work? the tubing having a smooth bore?
Now I know there will be knee jerks about directing the exhaust out at the front, i.e. in the direction of travel, and the instructions say not to do this, but I interpret the reason for this is that the pipe will fill with debris and water when traveling. I am intending (if I go this way) to install a knife valve, that I have at the very outlet which would be closed during travel.
My decision is not finale, I can take the exhaust across the underside of the van (east West), the amount of work involved for both plans is about the same.
Hi Aus-Kiwi, because of a tight 90' bend immediately on the outlet of the unit (because the chassis is in the way), I am making up an adaptor from 25mm stainless right angle, that I have. The standard corrugated tube wont bend tight enough to do the job. I can however use the corrugated tube after the muffler, (but it doesn't look as good as tube, and will need more support), however the main thrust of my question, is whether I can use a longer exhaust tube with it being smooth bore.
Just to add to this, the heater is being installed on the left hand side (awning side), just in front of the wheels. At the moment I am just formulating plans for the inlet and exhaust systems.
I would use a slightly larger pipe especially on bends . Try to use mandrel bends .. imo . Can always set it up test and keep an eye on it after fitting . ?
Hi iana. Just a thought - it might prove a pain in the backside, having to remember to open and shut the valve all the time. I have a master switch for power to the heater in the front boot, and you can guarantee that if I decide to run the heater out of the blue, in the middle of the night, it is off at that switch. My exhaust vents to one side of the van and the intake is on the other side.
Cheers, John.
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"My mind is made up. Please don't confuse me with facts."
A quick question aimed to those that might know. I am doing an install of a Snugger Diesel heater, and I am mounting it under the floor of the van. Now the instructions say that the maximum length of the exhaust pipe is 2 meters, and my reasoning for that is that the supplied exhaust tubing is corrugated, and a length longer than that would develop too much back pressure.
I have a few lengths of 25mm stainless tube left over from my boating days, and have a TIG welder at work, and am going to make up an exhaust pipe which will be smooth inside. I am thinking about directing the exhaust out at the front of the van as there are no opening windows there, the exhaust fumes will be well away from others, however the pipe length will be between 3.6 and 4 meters. Would it work? the tubing having a smooth bore?
Now I know there will be knee jerks about directing the exhaust out at the front, i.e. in the direction of travel, and the instructions say not to do this, but I interpret the reason for this is that the pipe will fill with debris and water when traveling. I am intending (if I go this way) to install a knife valve, that I have at the very outlet which would be closed during travel.
My decision is not finale, I can take the exhaust across the underside of the van (east West), the amount of work involved for both plans is about the same.
Maybe a dumb question but here goes.
Why are you taking it to the front where there are no windows? If you are too hot you will have the windows open and no heater. Too cold, windows closed and heater going.
Our heater has the intake for combustion facing forward and a 90 degree bend facing the side of the van, the exhaust runs to the rear using the 2 metre length of pipe also with the 90 degree bend facing outwards. Both on the awning side.
Can hardly hear the heater when it is running outside under the awning.
I have already had a chat to Roger, re installing the heater inside the cupboard above where I have already mounted the heater, when the sun comes out, I'll get some pictures, and post them.
Landfall, It was you who suggested the external installation, but the joys of the project become a nightmare when you have independent suspension and water tanks in the way, not to mention the volumes of pipework. Going back to the rear of the van would be real hard work.
Going forward is a similar installation, just "P" clips holding the exhaust pipe to the chassis, the only problem is the pipe will go past the gas cylinder storage, I believe I would have to route the exhaust 1.2m past them. The exhaust pipe going across, East West is an option, but support bracketing will be a pain, and the slide-out may allow fumes in to the interior. Going East West is the only route where I can have a pipe length of less than two meters.
Landfall you are right about the windows, and meetoo I have also thought of that, but a valve or cap would prevent wasps from making their home up the pipe as well.
Tomorrow it might stop raining and I can make further inroads to this ordeal.
Thanks all for your replies, didn't expect such a turnout.
The tread is swinging away from the original question, I would have thought covering the exhaust outlet with mesh, would be adding resistance to the flow and increasing back pressure, which was my query? however if I was at the point where I could just put mesh over the outlet/inlets I would be a happy boy.
Is there no way to mount the unit inside and route the inlet and exhuast through the floor as usual? I would consider this a more important issue, there are electrics within the unit that will not like rain from the road.
Apart from that, longer pipe shouldn't affect the performance, just go up a diameter or two in size so there is no back pressure.
Perhaps run the unit on a bench prior to installation and see how it goes by adding exhuast tubing?
Not sure that wasps would be a problem as you are supposed to run the heater for ten minutes per month, wasps would not be happy with this.
As for electrics the unit is in a sealed box when fitted externally.
The valve idea is a good one, we have a valve on the exhaust in our yacht, as when it heals over there is a risk of the exhaust outlet going under. If you do happen to forget to open the exhaust and start the heater up it shuts down very quickly when the internal sensors kick in and tell it that the exhaust gases are too hot.
