On site Dometic fridge /Freezer not working on gas ,, (4 Viewers)

[jerryz]

Im on site in Wales for 4 days watching the motorcycle racing at Aberdare ,, sit has no EHC so solar and gas only ,, the Fridge and Freezzer are not getting cold at all, opening up the burner is not lighting or working , i have 2 full gas cylinders and cooker and oven are fine as is Truma hot water .

The burner in the fridge unit is almost new and the flue was cleaned recently .. any ideas all my food is going off .

 

[Bessy765]

On ours the gas solenoid valve stuck shut, with someone inside turn the fridge off wait a couple on mins then turn on whilst you remove the lower external grill and give the valve a sharp tap not a big belt more just to rattle the valve. Have had to do this twice over about 10 years always worked fine afterwards.

 

[Jimbohorlicks]

I would still check the gas jet to make sure its mot blocked and has is getting through. If you have one-off those long gas lighters use that to light the gas or warm up the igniter to check if gas is coming through

 

[jerryz]

I gave the valve a few good taps , got it working nicely but came back 2 hours later and had to do it again so its a bit hit and miss ,, im not fully trusting it

 

[rosalan]

….except you have found the problem. The gas jet! New or not, the situation changed after hitting it. It does need removing and cleaning or replacing. You could run the engine for a while to hold the cold or place ice cubes in there for a while.

^{_{Subscribers  do not see these advertisements}}

 

[suavecarve]

….except you have found the problem. The gas jet! New or not, the situation changed after hitting it. It does need removing and cleaning or replacing. You could run the engine for a while to hold the cold or place ice cubes in there for a while.

Agree, see if you can freeze some bottles of water to place in fridge for when it may not be working. Neighbours freezers for this purpose are pretty good as well.

 

[GeoffnDee]

I thought that it was the gas solenoid valve that was tapped which got it working ? if so I would expect it to be a faulty/sticking gas solenoid valve problem. (it would be worth checking that the electrical connections on it are ok)

 

[1967bowesj]

Whats batteries like, is enough power getting to valve, is pcb board ok these do go bad a lot.

 

[Bessy765]

Try pouring boiling water over the solenoid valve

 

[LostInSpace]

A few gentle taps on the solenoid as you turn the fridge on and off could loosen up the solenoid.

^{_{Subscribers  do not see these advertisements}}

 

[jerryz]

t been working all day ok fridge is cold and freezer is frozen ,, but i still dont trust it ,, seems to be solenoid valve is intermittant ,, can they be changed ???

 

[Bessy765]

Yes there not difficult to change, care should be taken when undoing the gas pipes hot water on the body to expand the alloy,possibly slight tighten first if possible a pipe spanner (ring spanner with a gap in it) for now just set the fridge to it’s coldest setting less times for the valve to cycle on and off.

 

[jerryz]

Well its clearly got an intermittant fault.
The fridge freezer worked perfectly all day and night but this morning it was working until i drove home 100 miles , it worked ok on 12v but once parked up at home the gas had not ignited after more than an hour ,, so i reckon its the gas solenoid valve but I will take any advice if people consider its another issue

 

[Bessy765]

Clean the earth terminal on the body of the valve first, also check the hab battery voltage with the engine off.
And the engine battery when running.

 

[GeoffnDee]

Have you checked that the electrical connections (including earths) are ok at the valve / burner control device / burner chassis

^{_{Subscribers  do not see these advertisements}}

 

[jerryz]

Hab battery 13.2v , solar working too, engine battery is 12.9v engine off and 14,1 engine on

the 2 wire connections to Solenoid valve appear clean and secure but i will check them tommorow and the burner ones ,, with contact cleaner, emery cloth and multi meter ,,,,,,,, im knackered today

 

[jerryz]

OK Fridge has been completely turned off for 2 days , I know its fine on 12v and 240v
, switched it on just with gas ,, Nothing happened ,, then wacked the solenoid a few times , and turned the switches on off a couple of times ,, suddenly the fridge burner igniters start sparking loudly and after about 10 seconds the burner starts roaring .

But its not a reliable Gas start so should I just replace the Solenoid ,, Or the 5 pin relay in the Fridge burner compartment as it might be sticky or BOTH ?????

When 12v and 240v off I want it to start up reliablely every time .

 

[GeoffnDee]

Is it a 7 series Dometic fridge ?

 

[jerryz]

Yes RM 7605

 

[Brains]

Just keep in mind that a MoHo fridge will never fire up on gas within 15 mins of the ignition being switched on.

(Built in safety feature to ensure the pilot light done not ignite when refueling in a petrol station)

^{_{Subscribers  do not see these advertisements}}

 

[jerryz]

Just keep in mind that a MoHo fridge will never fire up on gas within 15 mins of the ignition being switched on.

(Built in safety feature to ensure the pilot light done not ignite when refueling in a petrol station)

yes i know Brains... but its not firing up even after a few hours or days

 

[GeoffnDee]

The gas valve power supply is controlled through the P810 burner control device which could also be the problem , the supply voltage at these items is not 12v and the Power module electronics appears to control the voltage , 1.5v at the P810 and the GV100 gas valve (According to the Dometic 7 series service manual)

 

[Brains]

Another issue to put into the pot of options.

Is the system refillable (Gaslow etc)?
If so, where did you last fill up ?
LPG from French fuel stations is well known for being full of residue which can gum up the filters.

Hence we have never bought autogas in France, always filled up elsewhere.

 

[jerryz]

Filled up recently at John Stayte Services in Stroud both tanks almost full

 

[mitzimad]

before buying a solenoid check there is there is the correct voltage at the solenoidoften you need voltage on both sides on mine it was 1.5volts

^{_{Subscribers  do not see these advertisements}}

 

[a900ss]

Following this with interest as your problem is very similar to mine. Dometic RMT7655 which is fine on EHU and 12V.

Gas is intermittent. Sometimes fine, sometimes not.

Brand new burner fitted by Dometic a few weeks ago.

It always tries to spark, I can hear the clicking but sometimes doesn’t ignite.

It always ignites if the fridge hasn’t been on. The longer the fridge has been on, the less likely it is to reignite.

I suspect the Gas Valve but the fact it’s intermittent and always works when the fridge hasn’t been used for a while suggests it isn’t seized or stuck to me.

I’ve checked voltage at the gas valve and it’s reading 1.3V as opposed to 1.5V as expected but I’m guessing that’s close enough or could it be the PCB that’s at fault? I have cleaned all spade connectors to the Gas Valve.

Feedback most welcome.

 

[GeoffnDee]

a900ss , the 1.3v at the gas valve is split between two valves inside the unit have you tried tapping it when it does not appear to be working , there is also an earth connection at the burner that is important for gas valve operation and could be worth cleaning.

 

[a900ss]

Just to refresh this.

I’ve rechecked and I’m getting 1.3V on the right hand sand of the gas valve but nothing on the left hand side. This is after I’ve cleaned all contacts.

Is this the P810 control unit or main PCB that controls the voltage?

Is the P810 easy to replace?

Any recommended Dometic engineers in the Bristol/Gloucester/Swindon area?

Thanks.

 

[GeoffnDee]

If you look in resources (bottom of this page) the Manuals for Motorhome stuff section has, on page 2 , The Dometic 8xxx series service manual with the information regarding the GV100 and checking it , on gas mode (page 15 ), which should be the same on your your 7xxx series fridge and may be useful.
The earlier 8xxx series , that is shown in resources , appears to be similar to the 7xxx series before they changed the 8 series to using a very different P860 control module which also used a different control panel.

 

[Rjcamper]

Clean the earth terminal on the body of the valve first, also check the hab battery voltage with the engine off.
And the engine battery when running.

This is what happened to ours, twice now in 5 years... Clean up earth and all works ok

^{_{Subscribers  do not see these advertisements}}