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Old 11-03-2008
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mbrund mbrund is offline
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Join Date: Dec 2007
Location: Georgetown
Posts: 112

Originally Posted by aclark View Post
Maybe I am looking at the wrong part. Can anyone verify the pump is located in line and above and in front of the boilers in the engine compartment? What I am looking at has two wires going to it and is plumbed in to the water lines for the Primus.

Each Primus has it's own pump. The pumps are located directly behind each Primus unit. The Primus units are mounted on a plate that sets down in the side compartment, the motors are also mounted to the plate that primus boilers are mounted to, but way behind them. If you look at the back of the primus boiler, you will see a hose coming out of the top of the boiler. This is the heated water outlet from the boiler, now look directly down from that hose and you will see another hose. This is the inlet hose. Now trace that hose (it heads toward the engine) and about a foot behind the Primus boiler connected to that hose will be the motor. Sometimes the motor is quit enough you can not hear it operating over the boiler. You can put your hand on the motor housing and feel it running. The easiest way to know if the motor is operating is to remove the cap off the overflow tank (there are two, one for each Primus) and see of there is water flowing into the tank from the hose at the top of the tank. The tanks are mounted in the engine compartment to the ceiling of the engine compartment on the right side and to the left of the rear remote key panel. If water is flowing into the tanks when the boilers are operational, then the motors are working. These tanks should be kept 1/2 full of 50/50 anti-freeze/water mix.

I believe what you are are seeing (above and infront of the boilers) maybe the overheat sensors. These sensors have two wires (forget the color, they may be red), and in the middle of the sensor there is a red reset button. If the water every gets overtemp or you run low on water and steam is produced, these sensors will open up and shut down the Primus. If that happens, you have to press the red-button to reset it (they are kind of like circuit breakers, but based on temp instead of power). It's either that or the spolan valve you are refering to. The spolan valve is controlled by a switch in the overhead cabinet above the pilots chair, and is marked summer/winter. When you flip it to summer, the spolan closes and allows the hot water from the boiler to only travel through the hot water heater to heat the hot water and keeps it from traveling through the coach and heating it up.

Hopefully I have not confused you more. If you would rather talk, give me a call and I can go into additional detail on the Primus. I just rebuilt both mine two weeks ago as I had a problem with one of them, and since I had to rip it out I just did both of them.
Michael Brundridge
1992 Bluebird WB40 (formerly owned)
2002 Prevost H3-45 Vantare (formerly owned)
Fredericksburg, TX
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