FOUR WINDS INTERNATIONAL 2007 Presidio, Owner'S Manual

Page: 144 / 173

PRESIDIO
During cold weather, it is important to keep ice from forming in the regulator, which will shut off
the flow of propane gas to the appliances. Have the supplier add a hydrous Methanol when
filling the tank for use during cold weather. Regulator freeze-up can occur in any weather if
there is moisture in the tank, or if the tank has been over-filled. Always use moisture-free
propane gas, and make sure the tank has not been filled beyond 80% of capacity. If moisture
has entered the tank, have the tank purged, or have hydrous methanol added by an authorized
propane gas supplier.
If you believe a regulator has been damaged or otherwise is not functioning, have it replaced
by a qualified propane gas service representative.
The term regulator freeze-up is a misleading one. Regulators and propane gas do not freeze.
However, the moisture that can be contained in the gas will freeze as the gas expands and
cools passing through the regulator. This freezing of the moisture in the gas can build up and
partially or totally block the passage of the gas through the regulator. Freezing can also occur
when outside temperatures are low enough to contribute to the freezing of the moisture in the
gas.
The source of the moisture is varied. It can occur at the refinery or gas bulk plant, in the rail
cars used to transport the gas, or even within the motorhome propane gas tank. Moisture in an
propane gas tank can occur when a tank service valve is left open, allowing moist air to enter
and become trapped.
A two-staged regulator helps to reduce the possibility of freeze-up because of its larger orifice
size, and the fact that heat is transferred through the walls of two regulators instead of just one.
There are several steps that can be taken to inhibit or prevent this from happening:
1. Make sure that the propane gas tank is free of moisture before refilling.
2. DO NOT overfill the propane gas tank.
3. Make sure to keep the service valve on an empty tank closed.
4. If freezing has occurred, have your propane gas dealer purge the propane gas tank
before refilling.
5. Add a hydrous methanol or other approved propane gas antifreeze or de-icing agent to
the propane gas tank.
6. Keep the regulator covered at all times.
11-4
PROPANE GAS SYSTEMS
Regulator Freeze-Up