So this weekend's project is replacing the Dometic 3-way fridge gas flue vent.
Bought a genuine replacement flue kit but old one has an extra piece that's not included with the new one - a white plastic cover over the flue with lots of holes in it. See pic below - old one on left, new one on right. Anyone know what this cover is for - insect/debris protection perhaps? Is it OK to install new one without it?
My understanding from memory is that Plastic piece with the holes is easy to break off its only joined to the AL tube at the top, you should also have a Plastic fitting with louvers to fit over the unit with holes in the plastic louver unit (heat disperser) lining up with the 4 holes in the square AL plate. The rectangular plate fits into the Plastic louvre plate to ensure the AL tube with the plastic vent is lined up correctly.
Note, the plastic bit with holes may have been eliminated as a cost reduction.
herks said
06:11 PM Nov 3, 2018
You are correct, the plastic screen is to keep insects out of the flue. Swap it over.
Mamil said
11:42 AM Nov 4, 2018
Thanks guys, if it's just insect protection, may do without it this time to improve venting of the flue gasses.
Meanwhile, I have another conundrum you might be able to help with.
As you can see from picture below there are two ally plates. One is attached to the flue and obviously goes on the outside wall of the caravan, the other is larger and squarer and I don't know whether this goes on the inside wall or also on the outside? The original installation (from new) had it on the outside, sitting directly under the other plate, but I don't really see the point of this, and it means the plastic louvred cover doesn't sit flat.
And the Dometic installation instructions aren't much help, as I've found some don't mention it at all, others suggest it's mounted on the inside wall, and others show it mounted on the outside wall!
All installs I have seen the square plate is on the outside, behind the rectangular plate. The reason.... maybe as a heat disperser, picking up heat from the pipe/rectangle plate.
The Louvered cover should line up with the holes in the square AL plate. I cannot recall whether the square plate fits into the Louvered cover and held in by the outside edge of the cover.
Mamil said
05:54 PM Nov 4, 2018
Hi Peter, OK outside it is!
Yes the holes line up with the outer plastic cover, but no there isn't a recess in it for the larger square plate, just the smaller oblong one.
Anyway, that's the way it was on the original install, I just couldn't really see the point of two plates - one on top of other, and the Dometic instructions were ambiguous to say the least!.
Thanks to your help I can now finish my weekend job - replacing the flue vent and adding an extra cooling fan. Now I've got more cooling, and more control over the cooling as I've added a switch and LED. Can have cooling fans off, auto (switched by the thermostat), or on all the time.
I feel better prepared for those hot summer days now...
You are correct, the plastic screen is to keep insects out of the flue. Swap it over.
Your call but you may want to rethink.
On gas, the condition, shape and cleanness of the flame is critical. If an insect/bug gets in and falls down to the jet and changes the flame condition in any way then the fridge operation (on gas) will be compromised. Google it if you have any concerns.
Mamil said
09:02 PM Nov 4, 2018
herks wrote:
herks wrote:
You are correct, the plastic screen is to keep insects out of the flue. Swap it over.
Your call but you may want to rethink.
On gas, the condition, shape and cleanness of the flame is critical. If an insect/bug gets in and falls down to the jet and changes the flame condition in any way then the fridge operation (on gas) will be compromised. Google it if you have any concerns.
Yes, but unfortunately the original one has been damaged by heat (reason I'm replacing the whole flue vent) and became very brittle and cracked, so more likely a bit of that will fall down inside the flue than an insect! New one didn't come with one, and they can't be ordered separately (already checked with Dometic) so doesn't look like I've got much choice.
-- Edited by Mamil on Sunday 4th of November 2018 09:05:36 PM
PeterInSa said
11:09 AM Nov 5, 2018
Re (On gas, the condition, shape and cleanness of the flame is critical. If an insect/bug gets in and falls down to the jet and changes the flame condition in any way then the fridge operation (on gas) will be compromised.)
Herks, makes a good point, sometime ago, I have seen kits with the plastic cap, so either your parts suppler lost the cap or they are not supplied with one anymore. However our van since new with the plastic covers 40cm by 15cm above and below the frig on the outside of the van has never had a plastic cap at the end of the chimney. Other things that can also impact the flame include soot and rust in the chimney falling down on the flame and there is a procedure to carry out this cleanup.
Peter
Mamil said
08:08 PM Nov 5, 2018
So, I asked Dometic about the plastic cap, and this is what they said...
That part is no longer used and as such is no longer part of the kit and the system will be fine to use without it.
So this weekend's project is replacing the Dometic 3-way fridge gas flue vent.
Bought a genuine replacement flue kit but old one has an extra piece that's not included with the new one - a white plastic cover over the flue with lots of holes in it. See pic below - old one on left, new one on right. Anyone know what this cover is for - insect/debris protection perhaps? Is it OK to install new one without it?
Thanks.
Note, the plastic bit with holes may have been eliminated as a cost reduction.
Thanks guys, if it's just insect protection, may do without it this time to improve venting of the flue gasses.
Meanwhile, I have another conundrum you might be able to help with.
As you can see from picture below there are two ally plates. One is attached to the flue and obviously goes on the outside wall of the caravan, the other is larger and squarer and I don't know whether this goes on the inside wall or also on the outside? The original installation (from new) had it on the outside, sitting directly under the other plate, but I don't really see the point of this, and it means the plastic louvred cover doesn't sit flat.
And the Dometic installation instructions aren't much help, as I've found some don't mention it at all, others suggest it's mounted on the inside wall, and others show it mounted on the outside wall!
The Louvered cover should line up with the holes in the square AL plate. I cannot recall whether the square plate fits into the Louvered cover and held in by the outside edge of the cover.
Hi Peter, OK outside it is!
Yes the holes line up with the outer plastic cover, but no there isn't a recess in it for the larger square plate, just the smaller oblong one.
Anyway, that's the way it was on the original install, I just couldn't really see the point of two plates - one on top of other, and the Dometic instructions were ambiguous to say the least!.
Thanks to your help I can now finish my weekend job - replacing the flue vent and adding an extra cooling fan. Now I've got more cooling, and more control over the cooling as I've added a switch and LED. Can have cooling fans off, auto (switched by the thermostat), or on all the time.
I feel better prepared for those hot summer days now...
Your call but you may want to rethink.
On gas, the condition, shape and cleanness of the flame is critical. If an insect/bug gets in and falls down to the jet and changes the flame condition in any way then the fridge operation (on gas) will be compromised. Google it if you have any concerns.
Yes, but unfortunately the original one has been damaged by heat (reason I'm replacing the whole flue vent) and became very brittle and cracked, so more likely a bit of that will fall down inside the flue than an insect! New one didn't come with one, and they can't be ordered separately (already checked with Dometic) so doesn't look like I've got much choice.
-- Edited by Mamil on Sunday 4th of November 2018 09:05:36 PM
Herks, makes a good point, sometime ago, I have seen kits with the plastic cap, so either your parts suppler lost the cap or they are not supplied with one anymore. However our van since new with the plastic covers 40cm by 15cm above and below the frig on the outside of the van has never had a plastic cap at the end of the chimney. Other things that can also impact the flame include soot and rust in the chimney falling down on the flame and there is a procedure to carry out this cleanup.
Peter
So, I asked Dometic about the plastic cap, and this is what they said...
That part is no longer used and as such is no longer part of the kit and the system will be fine to use without it.