Low flow on propane

[brocki]

A good friend bought a 2001 Isata Class B motor home.  It is in very good shape and all indications are it was very well cared for and maintained.  As they are new to RVing, we are helping them get it ready for travel and checking all the systems and explaining their operation to them.

Have encountered one problem.  The gauge says the propane tank is full and the owner said he had it filled earlier this spring but we are getting very low flow at the stove and refer.  It does NOT seem to have a manual master valve but an electric valve with the switch right near the tank.  We know that we are turning on the correct valve/switch because with the valve off we get no flow.  But with it "on"we are not getting enough vapor to maintain a flame at the stove nor enough to sustain ignition in the refer.  I find no manual gauge for  the propane tank, only the gauge panel which indicates the tank is full as the previous owner claimed.

Are we missing something here?

[rossboyer]

Probably the regulator needs to be replaced. 

[kaypsmith]

3 minutes ago, rossboyer said:

Probably the regulator needs to be replaced. 

Maybe the regulator, or the tank may have been filled by an incompetent LP filling station. If the tank was not properly purged, and the tank was overfilled, the same symptoms will appear. The tank can only be filled to 80% liquid, if more than this, does not leave enough room for the liquid to vaporize,

[brocki]

Regulator........... never thought of that.  Not something we can really check out.  I thought I would try to fire the water heater (it's on the other side of the MH to make sure we don't just have a pinched line crossing over in the unit.  I can open  the bleed valve a little and make sure I get vapor out of it.

Thanks.  Back to work.

[rsbilledwards]

I would bet on the regulator as well, others in the Safari community have had similar issues and ended up being the regulator. I carry one as a spare.

[wildebill308]

Let us know what you find. I would change the regulator almost as a maintenance thing on a coach that old. They arn't that expensive.

Bill

[bm02tj]

First shut every thing off for 1/2 hour then turn on slowly  

Also check for electric shut off hooked to gas monitor,check pressure at outlet and inlet of reg 

good luck  

[manholt]

You could also drive the rig to a LP store & have them check things out...could be that you don't have the 80% regulator (see Kay's reply), or it was not purged before fill up!  I put my $$ on the regulator.

[brocki]

Thanks all for the feedback.  I tried the furnace and the water heater, all in different parts of the RV and as expected, no ignition..  As I have no experience with propane devices or systems, we are going to agree with Manholt and let the experts take it from here.  We are also under some time constraint in that the owner has to leave a week from now for the east coast with a sick daughter for medical treatment.  Everything else has checked out and been tested fine so when this issue is corrected he is ready to go.  Thanks all for the "direction".

[manholt]

brocki, probably won't take more than an hour to fix & get new LP put in! 

I can't speak for everyone on this thread, but I wish your friends daughter, a speedy recovery! 🙏

[kevinnash]

This sometimes happens when the valve is opened too quickly. This sometimes happens when the burners are on before the propane tank is opened. T

[kevinnash]

That sometimes happens when the control knobs are left on after grilling.

[golfclubsadvisor]

Also check for electric shut off hooked to gas monitor,check pressure at outlet and inlet of reg ,

[rayin]

The firs step is to have the LP gas pressure checked, i should be 10.5-11" water column with a stovetop burner on. After that water column test confirms low pressure they will test the regulator, which may be replaced without emptying the ASME tank.

reference: https://www.warehouseappliance.com/blog/how-to-test-gas-pressure/  I would not construct that manometer, instead I would rent a digital manometer for 1/2 day, I merely posted it to confirm approved LP gas pressure downstream of the regulator.

 

  FWIW an LP supplier will not pump out your onboard tank due to liability concerns plus the possibility of contaminating their  large storage tank. My long-time LP supplier for our home told me to park the MH away from buildings and open the overflow(spitter) valve, allowing the LP to vent to atmosphere.

(mine took about 12 hrs to vent approx. 8 gallons)

 

Edited March 25, 2021 by rayin