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Topic: Primus Heat Owners (Read 1436 times) previous topic - next topic

Primus Heat Owners

I know there aren't many of us that have Primus Heat, but for those who do, I have a question. How often do you add glycol. I thought mine was full and after running and not getting heat I had to add about 6 quarts. Just curious because the system doesn't seem to be pressurized and where does it go? Does it evaporate over time? I don't seem to have any leaks. 
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #1
Joe, I am one of those Primus folks, but I can't offer any help. Ours is "in-op" because we cut the power and propane source. Maybe some of the others will chime in. I'll scan my factory manuals and see if they reveal any secrets.
Paul & Kathleen
1995 U320c SE 40'
Build 4681 --Cummins M11 /17511
"That Irish Girl"
Red MINI " 40"

Re: Primus Heat Owners

Reply #2
I can leak inside the combustion chamber, evaporate and exit with the flue gases once heated up and pressurized. I have seen that occur on boilers before.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Primus Heat Owners

Reply #3
Thanks for the response. I think because the system is not under pressure and I think when it gets hot glycol over time evaporates at a slow rate. Once the level gets low then air gets in the system and then no heat. Its really not a big deal but something I'll pay more attention to. 
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #4
I think the loss would be from a small leak. Have you checked the air bleeders on each side of the coach ?
If they are not sealing (tightly screwed in) they will release pressure and coolant.
The holding tank in the engine compartment becomes brittle with age, it could also be leaking, along with hose ends.
Have you disconnected the temp sensor located above the boilers? If it is connected it may have failed allowing the system to over heat and the excess pressure to boil off.

The best source of info on the Primus can be found on the Bluebird website (WONDERLODGE), many helpful bluebird owners with lots of experience with this system.

We Primus owners must circle the wagons and help each other, a great system but not much help if we have troubles.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #5
Lon, thank you very much for those ideas. Where are the air bleeders located. I will also check the overflow and temp. sensors. At first glance I don't think its the over flow, but I lost more than a gallon last night. If you can believe it its cold in Florida. Previous owner had the same issue but it all of a sudden has gotten worse. So what ever happened, its recent.   
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #6
The air bleeders are located on the heat exchanger pipes on each side of the coach. Your sofa is probably in front of the pipes on the drivers side. depending on your lay out you might be able to access them from under the sofa or remove drawers to get to them.
The passenger side should be accessible from next to the passenger seat. They look like little knurled finger screws, they should just be hand tight. Make sure you put a rag under the valve when you crack them open because antifreeze should leak out along with any air trapped in the line.
This is probably not your problem. If the bleeders were leaking the antifreeze would be all over your floor.
The system holds a substantial amount of coolant. It could be just low and an air blockage is not allowing the system to fill.
Is your pump running (located next to the boilers)?
Are both boilers firing?

The surest way to purge the system of air is to install a temporary 12v pump in place of the re-circulation pump installed.
I bought one at Harbor Freight for about $30. Tie your water lines into the higher output temporary pump and it will force the water through all the lines and push the air out into the coolant reservoir. It will also probably show you were a leak might be.

Remember, the Primus system encompass the entire coach. There are heat exchangers in the front under the windshield, along both sides, in the bathroom and under the kitchen sink, and in the bedroom on each side. It is plumbed to the engine for engine block heating and to the water heater for hot water. If your looking for a leak check everywhere.

My guess would be the coolant storage tank, a gallon is a lot of fluid. The tank is plastic and is probably as brittle as glass at its current age.

If you don't have the Primus paperwork let me know, I can send it to you. If you need any help don't hesitate to ask.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #7
Lon, I finally got to search for leaks and so far have found none. However the return line into the jug would not allow glycol to return. And so could the boilers just cook that glycol away. I have freed up the return line, filled the system and will try again. The fluid seems to drop slighty when started. and when shut off level should return to half full in jug. Your thoughts and anyone else please chime in. 
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #8
Can you see the fluid running into the holding tank when the system is on and a boiler burning ( depending on how much heat you require either  one boiler will light or if demand requires, both boilers will light)?

With an ignited boiler the pump should come on to circulate the fluid through the system. Have you confirmed that the pump is running?

Is the fluid getting hot in the holding tank?

Do you have the instruction manual for the system, do you understand how the control panel and the system work at all the combinations ( I found the manual confusing. It took and still takes me several read troughs before I grasp what its telling me to do to accomplish different things.)

If no fluid is returning to the holding tank a air block requiring bleeding could be the problem, or the line could be blocked someplace. I would suggest buying the $30 12v circulating pump at Harbor Freight and connecting it from the in and out lines on your system pump. The HF pump has a much greater flow rate than the system recirculating pump, It will force the air and any blockage through the system. The re-circulation pump with the Primus is a VERY low amperage  draw pump the gently circulates the fluid through the system.

DUPREE PRODUCTS sell parts for the Primus. The owner is a large contributor on the WONDERLODGE ( Bluebird) Forum. He is very knowledgeable about the system and is very helpful, don't hesitate to call him.

Don't hesitate to call me either if you need any copy's of the Primus Manual or for any questions.

1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #9
Lon, I do have the manual and also a parts list. I have spare parts even a new boiler. The pump is pumping and fluid is flowing back into the tank. Both boilers are on and my light is red. When system and temp is satisfied the  light turns green and ultimately  shuts off. I will need to get propane tomorrow. Then I will see if fluid is being heated. I think it is because the fins radiate heat and the boilers are hot. I am hoping that because the return line was pinched that was keeping fluid from returning and the boilers boiled away the glycol.  I also hope that when I check it tomorrow, the tank will still be half full. If not I'm back to looking for a leak. Thanks for your suggestions and help. Primus is a great heat source. To bad there are so few of us. 
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #10
Keep us all up to date, the only way for all of us to learn how to repair this system is from learning from the others.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #11
I'm just jumping in here to mention that I seem to remember folks on the Wanderlodge Owners Forum some years ago discussing Primus.  I think it's more common on those coaches. Maybe you could get some advice from those good people. 
1996 U295 36' WTBI

Re: Primus Heat Owners

Reply #12
Ok here is an update. Filled my propane tank yesterday. Talked to Steve Briles at Dupree products. He is also a member on the Wanderlodge forum. His suggestions where similar to yours Lon. I went back and found some possible sources of leaks. I tightened about 4 fittings which included the fitting on the overflow tank. Many of the fittings are the old fashion compression type and not the typical hose clamp. Also it appears when my return line was pinched the gloycol was forced out the overflow as I felt gloycol at the end of the hose. Tomorrow the temps are going to drop and I will run the system . I plan to put white paper towel under the overflow to see if it leaks.  I will see if fluid level stays the same or continues to drop. We shall see.
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #13
I will look forward to reading about your progress.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #14
Well its been three weeks since I reported my problem. Came down with a very bad cold which I just got over. System is still not operating. correction it operates but it still leaks. Today I went to the coach and filled the system with glycol. Then  I started the two electric heaters to circulate the system and purge it of air. Then I fired both boilers and started pulling off insulation from piping and looked for leaks. After 2 hours I gave up. I pulled the floor out from the closet because there is a fin tube and blower in there but no leak. So far the plastic jug does not leak. Connections to the boilers don't leak. Circulation pump does not leak. The ground around the boilers has evidence that that's where its leaking but I cant see anything. Plan to look again tomorrow. I plan to put a large pan under the area where I think its leaking maybe that will tell me something. 
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #15
On my Monaco with AH the leak was going out the exhaust from heat exchanger pin hole
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Primus Heat Owners

Reply #16
You have 2 boilers, can you disconnect each and run one at a time?
I have trouble with 1 of my boilers, I unplugged it and just use one. SOMEDAY I will remove the boilers and disassemble and clean them. After 23 years they MUST need some attention.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #17
Lon I should be able to. I will first run both with a large drip pan in the area where there seems to be glycol on the ground. If that doesn't lead to any thing I will unplug the secondary boiler first. Can I do that by simply pulling the electrical connections? Craneman thinks maybe there is a leak in one of the boilers. When I start the boilers I will start so only one boiler starts and then disconnect the other.
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #18
I just unplugged mine. I can't remember now but I think all you have to do is plug in the harness for  either and make it the primary or secondary. The harness is the same for both boilers.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #19
Well you Primus lovers, here is my current status. I pulled the primary boiler which is on the left when your looking at them. and while doing so I believe the leak was coming from connections behind the boiler. You cant see them they are to well hidden. I removed connections to both boils and replaced some hose and hose connectors. Some of those connectors where the spring type and not the worm gear type. I also replaceded some PVC tees and fittings. PVC can crack and you cant see it until fluid gets hot and expands the pipe. Everything is back up and running so now its time to monitor. Thanks everyone for your help and suggestions.
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #20
PICS?

Did you take the boiler apart?
If you can, at some point, could you take pictures of the wire connections on the gas solenoid?
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #21
Lon I didn't take the boiler apart. Is the wiring inside the boiler or behind the front black panel
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Primus Heat Owners

Reply #22
On mine its behind the boiler on the bottom. It attaches by a clip to the ignition solinod. 3 wires as I remember, VERY BRITTLE in the harness end.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Primus Heat Owners

Reply #23
I have a new boiler in a box I will look at that one.
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

 

Re: Primus Heat Owners

Reply #24
I have a new boiler in a box I will look at that one.

OMG!!!!!
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.