Guest Al redcay Posted March 30, 2022 Share Posted March 30, 2022 Dash vents won’t blow air , floor & windshield vents work ok Link to comment Share on other sites More sharing options...
Guest Ray Davis Posted March 30, 2022 Share Posted March 30, 2022 Defrost ( windshield ) is the default setting, so since the functions are vacuum operated you more than likely have a small 12v vac pump that's inop. Mine is on the firewall above the generator and looks like this. https://amzn.to/3zoXUED Link to comment Share on other sites More sharing options...
Jimmer Posted March 30, 2022 Share Posted March 30, 2022 May be a leaking vacuum line. Replaced my vac pump with a new Dorman but also ordered the wiring harness because the connection is different. Some Monacos use an aspirator system rather then the vac pump 1 Link to comment Share on other sites More sharing options...
Ivan K Posted March 30, 2022 Share Posted March 30, 2022 Al says, as I understand, that he can switch to floor mode so there is a working vacuum source. Maybe someone knows if his system uses vacuum solenoids or just a vacuum switch and where his door actuator is to test for vacuum there. Could be a simple hose break or disconnect, until verified. Link to comment Share on other sites More sharing options...
Guest Ray Davis Posted March 30, 2022 Share Posted March 30, 2022 5 hours ago, Jimmer said: Some Monacos use an aspirator system rather then the vac pump What is an aspirator system? Link to comment Share on other sites More sharing options...
Guest Al redcay Posted March 31, 2022 Share Posted March 31, 2022 I have a vacuum gadget on fire wall with a arm that I can move up an down but that doesn’t help with the amount of air out of vents. Link to comment Share on other sites More sharing options...
dl_racing427 Posted March 31, 2022 Share Posted March 31, 2022 14 hours ago, Ray Davis said: What is an aspirator system? Never heard it called that. My older Dynasty uses an air-powered venturi pump to provide vacuum for the dash air. The air supply to the pump is controlled by a Mac valve and a vacuum switch. Link to comment Share on other sites More sharing options...
Guest Al redcay Posted March 31, 2022 Share Posted March 31, 2022 Thanks for info but still nothing to to fix my problem, some is hard to understand. Link to comment Share on other sites More sharing options...
Jimmer Posted April 1, 2022 Share Posted April 1, 2022 On 3/30/2022 at 4:30 PM, Ray Davis said: What is an aspirator system? Same as venturi. A carburetor is a venturi. As air passes through the throat of the carb it pulls fuel into the air mixture. On the motorhome its air pulling air. You might google up venturi. 16 hours ago, Al redcay said: I have a vacuum gadget on fire wall with a arm that I can move up an down but that doesn’t help with the amount of air out of vents. That is probably your air induction box. Mine has two openings. When open it pulls fresh air into the dash. It is closed when Max AC is selected and recirculates inside coach air. I think there are electric actuators that open and close vacuum valves that direct the airflow to different levels. Link to comment Share on other sites More sharing options...
Guest Ray Davis Posted April 1, 2022 Share Posted April 1, 2022 10 hours ago, Jimmer said: Same as venturi. A carburetor is a venturi. As air passes through the throat of the carb it pulls fuel into the air mixture. On the motorhome its air pulling air. You might google up venturi. Thanks Jim, I'm familiar with venturi operation it's the term aspirator that left me not sure if that's what you were referring to. Link to comment Share on other sites More sharing options...
Guest Al redcay Posted April 1, 2022 Share Posted April 1, 2022 thanks but so far haven’t found the problem ,this is what they look like ,as you can see the lever I tried to move and it still doesn’t work. Link to comment Share on other sites More sharing options...
Jimmer Posted April 2, 2022 Share Posted April 2, 2022 11 hours ago, Al redcay said: thanks but so far haven’t found the problem ,this is what they look like ,as you can see the lever I tried to move and it still doesn’t work. My 03 Windsor is setup with no lever visible but functions the same. I closes the fresh outside air so cabin air is recerculated. Got have vacuum from your vac pump I see in your pic. Put a small line on the metal diagram, such on it road see if it opens. Link to comment Share on other sites More sharing options...
Guest Al redcay Posted April 4, 2022 Share Posted April 4, 2022 On 4/1/2022 at 10:55 AM, Al redcay said: thanks but so far haven’t found the problem ,this is what they look like ,as you can see the lever I tried to move and it still doesn’t work. I’m still looking for someone who knows something about my issue . Thought pics would help. Link to comment Share on other sites More sharing options...
Guest Ray Davis Posted April 4, 2022 Share Posted April 4, 2022 Al, well it looks like you have an hvac that's a little different, it looks similar but still it's different. Have you determined if the vacuum pump is producing vac? If it is I would try manipulating the vac hoses and see if they will change the operation. If you have vac, it seems to me that you have a broken or loose vac hose, a defective vac actuator or a problem with the dash control. Link to comment Share on other sites More sharing options...
Jimmer Posted April 4, 2022 Share Posted April 4, 2022 If the vacuum pump is not working then air blows out of all vents at a low air speed. I recommend the need to varify if the vacuum pump is working. I replaced mine because the pressure switch stuck on so it ran all the time. It also can fail to turn the pump on. I found a fuse, 7.5 Amp, for the pump and other functions in the FRBay. Link to comment Share on other sites More sharing options...
Guest Al redcay Posted April 4, 2022 Share Posted April 4, 2022 I have to run engine to check vac hose an I can’t tell if it works, but I can move that arm up & down an it doesn’t change. Don’t know how else to check vac hoses. 6 minutes ago, Jimmer said: If the vacuum pump is not working then air blows out of all vents at a low air speed. I recommend the need to varify if the vacuum pump is working. I replaced mine because the pressure switch stuck on so it ran all the time. It also can fail to turn the pump on. I found a fuse, 7.5 Amp, for the pump and other functions in the FRBay. Where is the pump and the fuse located. Link to comment Share on other sites More sharing options...
Ivan K Posted April 4, 2022 Share Posted April 4, 2022 (edited) Your pump is right there in your picture. The same type that Ray has posted in the first reply. It is electric so you don't need to run the engine. Only turn ignition to ON and feel if the pump is running and producing vacuum and if so, if it makes it to respective actuators or if it sucks air somewhere. Just follow the lines to start with. Looking at your picture again, I see the white lead disconnected at the pump so look into that first Edited April 4, 2022 by Ivan K Link to comment Share on other sites More sharing options...
Guest Al redcay Posted April 4, 2022 Share Posted April 4, 2022 That white wire goes to my window washer , but I moved the vac hoses off & on and now it’s working . So thank you all for your help. Link to comment Share on other sites More sharing options...
Jimmer Posted April 4, 2022 Share Posted April 4, 2022 3 hours ago, Ivan K said: Your pump is right there in your picture. The same type that Ray has posted in the first reply. It is electric so you don't need to run the engine. Only turn ignition to ON and feel if the pump is running and producing vacuum and if so, if it makes it to respective actuators or if it sucks air somewhere. Just follow the lines to start with. Looking at your picture again, I see the white lead disconnected at the pump so look into that first you have good eyes. 31 minutes ago, Al redcay said: That white wire goes to my window washer , but I moved the vac hoses off & on and now it’s working . So thank you all for your help. Yeah. Motorhomes are always teaching us. Link to comment Share on other sites More sharing options...
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