Whistling Noise in Propane Bay of 5th Wheel When Heater is Running

Question:

I have a 2021 Grand design reflection 5th wheel. It has two 30 lb. bottles. When the furnace is on the left tank, all is great. When switched to the right tank, the system makes a very loud whistling sound. Dealer is of no help at all. They told me its OK.

asked by: Gene M

Expert Reply:

Let's differenciate between whistling, whining, or humming. The regulator has a diaphragm that oscillates and can make what is called a humming noise, and that is normal operation.. If you have whistling, then read on.

There are several possibilities related to a whistling noise when using propane. Let's start with safety. If you smell gas or hear a hissing noise around your tanks or lines you may have a leak and need to use some soapy water on all parts and joints to see if it bubbles indicatingt a leak. If so, you will need to repair or tighten joints. For threaded joints use JR Products # 37207-30025 propane joint sealant.

Next determine if the cause is the propane tank(s), the automatic change valve, or the regulator. First, disconnect both tanks and swap positions. Did the whistling move with the tank or stay in place? If the whistling moved with the tanks then perhaps the tank has an issue - like being overfilled. Weigh the tank. The maximum weight of the tank will be 30 pounds plus the "tare" weight. This weight will be stamped in the ear of the tank and will be around 25 pounds. So a full tank will be 30+25= 55 pounds. If it weighs more you will need to have some removed or swap the tank.

If the noise did not move when swapping tanks, then the problem is likely with the regulator or the automatic change over switch which are usually made as one assembly. If you are tired of hoping for your dealer to do something then you can purchase a new one. The MB Sturgis # 888001-MBS is a good sized regulator with automatic change over for your tanks.

expert reply by: Les D