Blocking the Fridge Screen

Submitted: Monday, May 18, 2015 at 15:18
ThreadID: 117898 Views:1665 Replies:3 FollowUps:9
This Thread has been Archived
Hi all,
I have just seen a different type of blocker for the bottom screen of the fridge on a caravan, to keep the dust out.
It has aluminium rope track rivetted top and bottom and a piece of stainless sheet metal that slides in the track, covering the screen.
I have seen beer box cardboard used and another one was a sheet of Gladwrap wrapped around the screen (take it off first!) and then fixed back in place.

My question - does blocking off the screen affect the fridge? Usually only on there while driving, a few hours, but possible bad effects.

Thanks

bill
Bill B

Member
My Profile  Send Message

Back Expand Un-Read 0 Moderator

Reply By: Notso - Monday, May 18, 2015 at 16:16

Monday, May 18, 2015 at 16:16
Depends on whether you run the fridge whilst driving. I don't unless it is stinking hot and we are travelling for a long time. But yes it will affect the cooling capacity of a system that already doesn't work all that well on 12 volt.
AnswerID: 553923

Follow Up By: Nomadic Navara - Wednesday, May 20, 2015 at 08:39

Wednesday, May 20, 2015 at 08:39
"a system that already doesn't work all that well on 12 volt."

If yours does not work properly on 12 V then fix the problem. The four that I have run on 12 V have been OK. You just need to replace the wiring with cable that conforms to the Dometic specifications.
PeterD
Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

0
FollowupID: 839923

Follow Up By: Notso - Wednesday, May 20, 2015 at 09:05

Wednesday, May 20, 2015 at 09:05
So are you saying that your fridges are as effective on 12 volts as they are on gas or 240 volt? I think not. They work, and will keep the fridge cold but they are:

"a system that already doesn't work all that well on 12 volt."
0
FollowupID: 839925

Follow Up By: Notso - Wednesday, May 20, 2015 at 10:54

Wednesday, May 20, 2015 at 10:54
Extract from the Thetford 3 Way Fridge Manual, I guess they'd know?

"DC operation guidelines:
DC operation is intended only to maintain the temperature of the
refrigerator and its contents when they are already cool.

The DC operation is not intended for the initial start up and
cooling of the refrigerator. Always use either the AC operation
or propane gas operation to initially start up and cool the
refrigerator.

The refrigerator must be cooled and the temperature
must be steady before you operate the refrigerator on DC."
0
FollowupID: 839934

Follow Up By: Nomadic Navara - Wednesday, May 20, 2015 at 11:41

Wednesday, May 20, 2015 at 11:41
Notso, the later model Dometic fridges have the same size element on 12 V as they have on 240 V. They are capable of the same performance on 12 as they are on 240 V. The earlier ones do not have thermostats in the 12 V line so the element power is reduced a bit to stop them freezing the contents when the wiring to the fridge is of the proper size. Those who continue to say that the Dometic fridges are no good on 12 V are those who have them and refuse to or don't know they should upgrade the cables all the way from the alternator to the fridge.


PeterD
Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

0
FollowupID: 839935

Follow Up By: Notso - Wednesday, May 20, 2015 at 12:24

Wednesday, May 20, 2015 at 12:24
Two things, the original post says nothing about the fridge being a "Later Model Dometic", and when you say they have the same size, I seem to recall reading the dometic specs a while back that basically says the 12 volt has 170 wats and the 240 has 180, so it is a little less. There is one other aspect and in the ideal world where caravan manufacturers do put in decent wiring then a 12 volt will work reasonably well, but as we all know the world is not perfect and many installations are less than ideal. A small amount of resistance in connections and attenuation over distance can make a huge difference in the 12 volt system.
0
FollowupID: 839938

Reply By: Batt's - Tuesday, May 19, 2015 at 14:26

Tuesday, May 19, 2015 at 14:26
Unless you're traveling on dusty roads a lot I wouldn't bother I think you're better off letting it breath especially a 3 way fridge. Or you could set it up with some brackets or something so you can slide a piece of thin foam over the vents while traveling to help keep some of the dust out but it can still breath. Or you could try one of these http://www.ebay.com.au/itm/CARAVAN-FRIDGE-VENT-WITH-FAN-WITHOUT-FAN-/201349695225
AnswerID: 553956

Reply By: Member - bbuzz (NSW) - Tuesday, May 19, 2015 at 20:43

Tuesday, May 19, 2015 at 20:43
Thanks guys,
I have blocked it off previously but didn't monitor the temp.

I am going down the Darling soon, so will block off the bottom screen and monitor the temp in the fridge with the fridge on 12v and then turn it off while travelling.

I will get some figures to compare.

Thanks for the thoughts,

bill
Bill B

Member
My Profile  Send Message

AnswerID: 553981

Follow Up By: Nomadic Navara - Wednesday, May 20, 2015 at 08:36

Wednesday, May 20, 2015 at 08:36
Why block it off? In over 200,000 km of travelling I have not had much dust enter the fridge cavity. If you are getting dust into the van through there then fix that problem, it means that the fridge cavity is not sealed from the van interior like it should be.

If you block the bottom vent you are likely have the working parts of the fridge overheat if it is run with the cover on. You never know what helpful assistqant will start it up without removing the cover.
PeterD
Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

0
FollowupID: 839921

Follow Up By: Member - Rod N (QLD) - Wednesday, May 20, 2015 at 09:17

Wednesday, May 20, 2015 at 09:17
Thanks for posting that Peter. My thoughts exactly but I was a bit slow in posting such.
If a cavity is sealed there won't be much dust entering. There really needs to be a flow of air containing dust for dust to accumulate in a cavity.
0
FollowupID: 839926

Follow Up By: Nomadic Navara - Wednesday, May 20, 2015 at 11:46

Wednesday, May 20, 2015 at 11:46
I have travelled a lot of dusty roads. There is only a couple of millimetres of dust on the floor of the cavity. I consider it is not sufficient to worry about. The fins on the back of the fridge are fairly clean and it works efficiently in hot temperatures.. As I said above, if you are getting any dust from the fridge cavity into the van then the fridge is not installed according to the regulations and you should have it attended to.


PeterD
Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

0
FollowupID: 839936

Follow Up By: Batt's - Monday, May 25, 2015 at 11:11

Monday, May 25, 2015 at 11:11
I think it is also a legal requirement to have an open vent in a van behind the 3 way fridge so if your van happens to catch fire and the vent is found to be blocked it may create so extra problems just for the sake of trying to eliminate dust that may not even get in. So blocking it off with something like foam as I mentioned that can still breath or fitting exhaust fans will be a safer option than blocking it off with say cardboard or a piece of ply or similar.
0
FollowupID: 840191

Sponsored Links

Popular Products (13)