9/19/05 Maintenance Tip: Time To Check Those HEATERS!

[Capt._Chaos]

Yeah, I know! It's still pretty warm in most areas of the country, and most everyone's trying to keep their cool! I called home (San Antonio, Texas) today, and it's still a toasty 96 degrees down there! :yikes:

If you travel anywhere up north, you probably already know that it will begin to get a bit chilly up there at night, and before long, WINTER!

While it's still nice enough out, and you're not headed to Minnesota later in the year when it will be getting bitterly cold, it's a good time to check out that heater and see if it works!

Usually, most people will shut off the hot water valves going to the heater core in the spring, and then forget they had done so until they really need some heat in that cab! :wtf:

If you go to open those valves, and antifreeze is leaking out, then the valves needed to be replaced anyway.

Also, most older trucks have a cable-controlled heater control valve that may need attention, and/or replacement. Bypassing it is not a good idea, as it can get too hot in the cab, leaving you with no way to adjust the temperature to get comfortable.

If you have a newer truck, it may use electronically-controlled solenoids. Cycle your temperature knob between cold & hot several times to make sure they are not stuck. If no heat, even with your water valves open, then you will need to see if the solenoid is getting power when it is needed. If it is, and no heat, then the solenoid is bad.

Get prepared to stay warm, and be safe!

[Uncle Truck]

The electric solenoids are often used in the sleeper portion of Freightliner trucks, and can be a real hassle. More often they stick open, giving heat all the time. There is a well-known problem with the electrical connector to this solenoid, PM me for details as I would have to type a 30 page novel to explain how to fix it here :D A lot of people replace the solenoid multiple times and its not really the problem.

Also check your truck's cooling system before the cold sets in. As thermostats are often open much more during the hot summer months, as it gets cold old thermostats sometimes don't like to close all the way, then the engine will run too cold to give you any heat, coolant needs to be about 170 degrees for the heater to keep you warm. Some engines have two thermostats and both should be replaced if in doubt.

-UT-

[shewolf]

This is the same problem we are having with the Freightshaker we are driving. Right now we have the water valves shut off.

It got cold the other night in NH and we turned the valves on to get a little heat. When we did that we had no temp control in the bunk, the heat is on wide open and you cant get it to regulate or even get the AC to work when the water valves are open.

So does that sound like the solenoid you are talking about or the temp control switch or as Freightliner suggested today (without checking), a water valve? We are putting off the repair for a bit until heat is needed (owner paid about $1200 for repairs this week already) but will be helpful to know if possibly something Hubby can fix like a switch in the bunk.

BTW, it appeared we had thermostat problems too and we had those changed. The truck temp was running around 180 during the day but when it got down in the 40s in NH and we tried to get heat, the truck temp wouldnt get over 140 going down the road. Hubby had to use cardboard on front to get temp up enough to get heat. So we had both thermostats changed this week.