Seneca/Accolade Cab Heater

[EA37TS]

2020 Accolade 37TS with less than 1,500 miles. Went to the dealer today to have some warranty work done. On the way there this morning the outside temp was about 30 degrees and engine temp was approx 185 degrees. The cab heater blew nothing but cold air. Coming home this evening the outside temp was about 48 degrees, engine temp again was 185 degrees and the cab heater blew nothing but cold air. When I say blew cold air I don't mean cool, I mean cold, outside temp air. BTW, the distance driven each way was approx 40 miles on an interstate highway.

Thoughts on what I might check before heading to the Freightliner dealer.

[Rustynuts]

Well I would probably start by checking under the hood, I have never messed with it but I remember seeing a valve on the passenger side, up by the valve cover that runs to the heater to control the flow water to the heater box, it might be turned down or off....I’ll try and find a pic of it....Finally found a pic. If that doesn’t help, I would try pulling the black panel below the dash on the passenger side, I think it’s like 3 Torx screws hold it on. Then just check to make sure all the control wiring is firmly connected as They have this area apart yo run camera and other wiring up to the dash.

[EA37TS]

Originally Posted by Rustynuts

Well I would probably start by checking under the hood, I have never messed with it but I remember seeing a valve on the passenger side, up by the valve cover that runs to the heater to control the flow water to the heater box, it might be turned down or off....I’ll try and find a pic of it....Finally found a pic. If that doesn’t help, I would try pulling the black panel below the dash on the passenger side, I think it’s like 3 Torx screws hold it on. Then just check to make sure all the control wiring is firmly connected as They have this area apart yo run camera and other wiring up to the dash.

Many thanks. I'll give that a try. I also noticed coming home that the USB charging port on the bottom of the dash was not charging my iPhone. I'll have to check that out as well and that could be an indication something is amiss behind that dash panel.

I'll go out this afternoon when the temp gets above freezing and look around.

[EA37TS]

Rustynuts

Many thanks. That valve on the engine appears to have been the issue. The valve was in the closed position, as displayed in your pic. I opened the valve and then after idling for a few minutes the air from the heater started getting warm.

Pic of mine in the open position now.



As a note, I was reading on the web where Freightliner installed a valve like this on the Cascadia because the heater flow valve has a groove that allows hot water to flow through the heater core causing hot air in the cab and sleeper even in the summer months. This way drivers can shutoff the flow of hot water to the heater during hot summers. I guess that makes sense.

Now another issue popped up today and my Malfunction Indicator Light came on. May be a trip to the Freightliner dealer anyway.

[Rustynuts]

Yeah I knew about the valve as they were on the Freightliner FL70 delivery trucks I used to have. It was nice to be able to cut the water flow and kept the cab much cooler.

[RoWest]

On our unit, the USB is for inputting music or video through a flash drive. It will not charge phones or tablets. Get a USB insert for the cigar lighter and you can have multiple USB outlets with higher amps for fast charging.
example:
https://www.amazon.com/gp/product/B07BJ3MNVQ/

[Rustynuts]

It just depends on the head unit as this is just an extension cord that plugs into the back USB port of the stereo head. We have the Garmin/Fusion unit in out 2018.5 and the remote USB port will charge a phone, used for music and used for updating the head unit and removable tablet. Since I have so many things like cameras, phones, iPads, drone, I have added ports all over the coach and since both the wife and I have phones and I use an old phone just for music I swapped out the dash power port for a dual USB port and I have another 2 dual ports mounted in the Build 5 Fab console. Even added them in the storage compartments and the outside tv.....can never have enough USB ports

[Lve2fsh]

Old post but does anyone know if the 2014 Seneca’s M2 frames have this shut off valve? I can’t seem to find one and suspect my heater is fighting my ac.

Originally Posted by EA37TS

Rustynuts

Many thanks. That valve on the engine appears to have been the issue. The valve was in the closed position, as displayed in your pic. I opened the valve and then after idling for a few minutes the air from the heater started getting warm.

Pic of mine in the open position now.

Attachment 55377

As a note, I was reading on the web where Freightliner installed a valve like this on the Cascadia because the heater flow valve has a groove that allows hot water to flow through the heater core causing hot air in the cab and sleeper even in the summer months. This way drivers can shutoff the flow of hot water to the heater during hot summers. I guess that makes sense.

Now another issue popped up today and my Malfunction Indicator Light came on. May be a trip to the Freightliner dealer anyway.

[SloPoke]

Long long ago... I checked our Seneca after reading this post... and did not find anything resembling the valve on our 2015 M2. Not that I don't think it would be a good idea.. but maybe Jayco was supposed to remove the valve - or open it when they completed the assembly -


I left it as one of the new features of the later models. .