Cold Weather Issues?

[RVNeophytes2]

I thought I'd float this, in case it helps anyone. A few maintenance and operational items from this Texas - Maryland - South Carolina - Texas trip in freezing weather.

• Power Steering I've done two roadside repairs,* one to remove and replace a cracked hydraulic cooler core, the other to correct a filter "gasket hernia." At issue: higher pressures associated with cold weather ops. In both cases, the rig was warmed up for ten minutes before driving.
• Water Hose We forgot to retract the water hose after filling one night, and entire day in a heated compartment was not enough to thaw it. Worse, to save space (we were hauling freight), I'd hung the spare drinking water hose (to use for manually filling) in an unheated trailer, so it was a solid coil of ice. The solution was to completely extend the coach hose from its reel, coil it inside a bucket of hot water. Remember, those shutoff valves might not function, in extreme cold. I see lots of frozen lakes around various rigs.
• Batteries We've been involved with two different rigs whose owners inadvertantly ran down house batteries using a space heater driving down the highway. Running the generator enroute like we all do in the summer for air conditioning is the solution.
• Aqua Hot Remember that AH doesn't heat the coach unless the AH block heater is on, driving. Else, you have to run the diesel burner, too. At the campground, diesel and 110VAC functions can be run together. The added advantage of this technique: you don't have to remember to turn on the AH block heater for the overnight.
• Generator It might not start, due to cold. I'm going to invest in a block heater for the generator.
• Chassis Batteries A diesel mechanic buddy turned me on to Cabela's Pro Series battery tenders. I mounted one on the outside wall of my chassis battery bay, plugged it into the aft block heater receptacle. It optimizes those batteries nightly for that critical morning start under arctic conditions.
• Sewer Of course, leaving a sewer hose outside can be just as lethal as leaving a potable water hose out. Inchworm the hose to rid it of gray water, and stow before bed. To prevent slide-valve freezing, I pack a wet towel around the port through which the power line extends, eliminating the cold draft that enters my utilities compartment downstairs.
• Tires Removing a TPMS transmitter from a frozen valve stem for manual measurement will earn you a surprise: it will free flow. Tires should be inflated to manufacturer's load inflation table value -- don't use the placard by the driver's seat -- minus 1 PSI for each ten degrees under 65F.

*If you dump power steering fluid, about ten seconds of normal steering is available, after which it gets progressively harder. In my rig, manually steering into a parking space (I was lucky enough to blow my core 1/4 mile from a truck repair shop) required more than 100 lbs of force on the wheel.

[RVNeophytes2]

I forgot to mention: Dry snow on the toppers seemed inconsequential. I motored the slideouts in and out, to sweep them. The full-length slideout wouldn't close completely at the upper edge; it turns out the dry snow collected, got rolled up and formed into an obstructive snowball er... snowtube. That merited a climb atop the rig with a broom

[billdreamlv]

This is all very good information. A year ago I was in Reno in freezing temps and it rained the night before. When I pulled the jacks up, two of the jacks didn't respond and stayed down. The jacks were frozen to the asphalt. I took a hammer and tapped the base of the jack stand and, wham, the jacks retracted immediately. Scared the you know what out of me. So, if it rains and then freezes take a hammer to the base of all four jacks before you try and retract the jacks, just to break the ice.

[DeWat]

Originally Posted by RVNeophytes2

I thought I'd float this, in case it helps anyone. A few maintenance and operational items from this Texas - Maryland - South Carolina - Texas trip in freezing weather.

• ...
• Aqua Hot Remember that AH doesn't heat the coach unless the AH block heater is on, driving. Else, you have to run the diesel burner, too. At the campground, diesel and 110VAC functions can be run together. The added advantage of this technique: you don't have to remember to turn on the AH block heater for the overnight.
  ...

*If you dump power steering fluid, about ten seconds of normal steering is available, after which it gets progressively harder. In my rig, manually steering into a parking space (I was lucky enough to blow my core 1/4 mile from a truck repair shop) required more than 100 lbs of force on the wheel.

I think you have the AquaHot backwards. The block heat switch ("Engine Pre-Heat") does not have to be on to heat the coach while driving. While not as efficient as the diesel burner, the engine's heat will provide the heat to the AquaHot for the coach. What the engine pre-Heat switch does is use the AquaHot's heat to help pre-heat the engine before starting.

[RVNeophytes2]

Originally Posted by DeWat

I think you have the AquaHot backwards. The block heat switch ("Engine Pre-Heat") does not have to be on to heat the coach while driving. While not as efficient as the diesel burner, the engine's heat will provide the heat to the AquaHot for the coach. What the engine pre-Heat switch does is use the AquaHot's heat to help pre-heat the engine before starting.

Thanks, folks. That was my understanding, too. DW looked it up and told me otherwise. I'll try to find the citation from our friends at AH.

That was easy, you were right. "NOTE: The Aqua-Hot's Engine Preheating System acts as a supplemental heating source in addition to the Diesel-Burner and the Electric Heating Element(s). While traveling, the engine's heated coolant will
automatically pass through the Engine Preheat / Motoraide System,
transferring heat into the Aqua-Hot's Boiler Tank. This design feature
reduces the total operating hours of the Diesel-Burner and the Electric
Heating Element(s)."

She's a lawyer, and should have been able to discern that subtle automatically difference.

Thanks for the correction.

[Lt Dan]

Originally Posted by RVNeophytes2

[*]Batteries We've been involved with two different rigs whose owners inadvertantly ran down house batteries using a space heater driving down the highway. Running the generator enroute like we all do in the summer for air conditioning is the solution.

If you are running a space heater on an inverter and your house batteries run down while driving then you have a charge solenoid problem. Your engine alternator should be charging the batteries while driving if your boost/charge solenoid is working correctly. It is also possible that the amperage draw of the space heater is too much for the inverter.

[MisterT]

I made some mistakes early on in our journeys while in freezing temps:

-Walmart corporate parking lot overnight in January '15 during sleet and freezing temps...set the AGS to kick on the generator at 10.9 volts, but didn't realize that the generator cranks from the HOUSE batteries that were now too low to crank it! Thank you Mr AUX booster switch, I now know what you are for as well... and thank you Mr AGS, I now set your Volts to crank at 12 or higher : )

-GrandCanyon RV park during January and two inches of snow both nights... left the water hose connected to park water all night. Those things are hard to handle when they're cold, not to mention the nightmare when they are frozen! I set out an electric heater on both ends, and several hours later we were back in business. Now I just go with the onboard water pump during overnight hours and leave the park water to itself.

-GallupNM RedRocks campground ... beautiful night, but same as above... but decided I was smarter and wiser now, though - I left the water hose hooked up and added a electric heater to the spigot end of the hose and in the wet bay overnight - it worked. Aint' I smart! : )

-All really cold nights, including those above... the way our coach main slide is built, there are several areas that air and cold can enter the living areas - it is much better sealed and more easily heated with the slides IN. On these REALLY cold nights, we bring in the slides at bed time. Our advantage is that everything, other than a bedroom drawer or two, is just as accessible with the slides in.

[Tireman9]

Originally Posted by RVNeophytes2

I thought I'd float this, in case it helps anyone. A few maintenance and operational items from this Texas - Maryland - South Carolina - Texas trip in freezing weather.

SNIP

• Tires Removing a TPMS transmitter from a frozen valve stem for manual measurement will earn you a surprise: it will free flow. Tires should be inflated to manufacturer's load inflation table value -- don't use the placard by the driver's seat -- minus 1 PSI for each ten degrees under 65F.

SNIP

Couple comments

1. I would shoot the threads of valve stem w/ WD-40 to remove moisture. Also a little shot in the TPM sensor battery chamber and ensure the "O" ring is in good shape.
2. I would run the TPMS and rely on its readings as long as ambient is in the operating range stated by TPMS company.
3. Your inflation pressure at the start of every travel day should be the minimum needed to support your measure load on the heavier end of that axle, or placard if you haven't confirmed you are not overloaded.
4. You should NOT make any calculations for change in ambient temperature i.e. your 1 psi for each 10F. You should use your placard inflation or the inflation based on your measured load as mentioned above.

Side note Tire inflation pressure change is about 2% for each change of 10F. Here is the math. so 1 psi is only close for passenger and LR C & D tires but not for LR E and above.

[twinboat]

Originally Posted by Lt Dan

If you are running a space heater on an inverter and your house batteries run down while driving then you have a charge solenoid problem. Your engine alternator should be charging the batteries while driving if your boost/charge solenoid is working correctly. It is also possible that the amperage draw of the space heater is too much for the inverter.

Running a 1500 watt electric heater will draw 125 amps DC. At that rate the alternator will have a difficult time keeping up. At idle and slow speeds, it won't.

Once the combined battery banks drop below 13.2 volts the BIRD, IRD or othe logic controller will open the isolation relay. When this happen, the batteries voltage drop quickly and the isolation system will not be able to recover and maintain 13.2 volts while charging. The alternators prime purpose is to maintain the chassis battery.