Alternative Cab Heater Opions / Options

[joesco]

Thanks to Jarhead, I finally finished the installation of my new in-the-cab heater. Using a 15 amp in line fuse, I wired it to the existing OEM switch. I used the passenger and driver's defroster ducts and this unit blows much better than the Hunter OEM. But the test will be in another month or so when the NH winter arrives. I'll post pictures later this week.

 

[MtnSnow]

Make/Model of what you installed?

 

[joesco]

Pm sent

 

[joesco]

Sorry for the late in posting my picks for the new heater, had been down with some health issues. I plugged my truck into the 1200W block heater last week, when it was 17 degrees, of course the truck started on a half a crank, took it for a ride and I had great heat in the cab. Here are some mostly finished pics. This week, I had to purchase a PVC elbow for the driver's side vent hose to connect it to the heater, added a few tie wraps for the wiring, and some form insulation around the heater hoses on the newly installed 1/2 plywood on firewall . I also wired in a 15amp fuse into the wiring for the existing switch.

 

[rosco]

The ultimate heater is the fuel fired heater (FFH). That does the job, even here. No Bull. But.... there are lots of more temperate conditions, where you don't want to run the FFH, and a hot water heater would do the job nicely, especially after you get rolling on a trip that lasts several hours. To up grade a water heater, add a 2nd or 3rd core to it. Hook them in series so you get full flow with non leaking shrouds to direct the air flow. Lots of times, its not that there isn't enough heat in the cab, but that its not being moved around enough, or in the right places.

 

[jarhead1086]

I was chicken to post anything until I knew it worked. I looked at some heaters at JC whitney as well but they were bigger. I think this heater will be great for me with my well sealed hardtop in weather that rarely gets below zero. The block heater, like Joesco said, really helps out. I can run mine with my Honda generator when I am camping to get all that cast iron pre-warmed up. I think all you AK, ND, MI, MT type guys, especially with soft tops, would be safe to have an additional heater or one with more BTU's and more CFM. I believe the fuel fired heater really works, but the original heater sucking cold air with a weak, dirty blower was not always enough.
I just replaced my glass, added extra weather strip, and siliconed the hinge joints. The painted rubber skirts curl up over time. I masked mine during paint and Armorall'ed them after. Replaced the crappy slotted arm screws with stainless allen heads so now they don't flop around and actually work. Add some grease to the wing nut threads so they don't bind up too. Working on electric wipers next.

 

[joesco]

I priced out FFH as I had one in my Unimog 421 years ago and the least expensive unit I found was $995.00! Thanks for the suggestion on multiple cores, never thought of that! !

 

[74M35A2]

I also thought of multiple cores, especially since the heater box is so large to be able to accommodate it. But, my concern here is the volume of airflow. It seems somewhat low to begin with. Adding additional cores will reduce this further again.

My heater had poor performance, and it ended up being the heater core was mineral (corrosion) filled. It didn't leak, and flowed well, but could not transfer heat well. There is a thread about an S-10 heater core that nearly fits, and is like $20 brand new. Try that.

Also, you can add the 30,000BTU fuel fired heater to any M939 in place of the heater core type heater. Somebody had brand new 30,000BTU kits for $300 in SS classifieds recently. From there you really only need the brackets and to mount it, which are an active available NSN number. I did so, but don't have it installed yet. Also need to upgrade the 3(?) outlet hoses from the diverter box to the higher temp orange ducting.

 

[JohnnyBM931A2]

I also thought of multiple cores, especially since the heater box is so large to be able to accommodate it. But, my concern here is the volume of airflow. It seems somewhat low to begin with. Adding additional cores will reduce this further again.

My heater had poor performance, and it ended up being the heater core was mineral (corrosion) filled. It didn't leak, and flowed well, but could not transfer heat well. There is a thread about an S-10 heater core that nearly fits, and is like $20 brand new. Try that.

Also, you can add the 30,000BTU fuel fired heater to any M939 in place of the heater core type heater. Somebody had brand new 30,000BTU kits for $300 in SS classifieds recently. From there you really only need the brackets and to mount it, which are an active available NSN number. I did so, but don't have it installed yet. Also need to upgrade the 3(?) outlet hoses from the diverter box to the higher temp orange ducting.

I would love to go the FFH route.. The heater is pretty terrible in these things. And if this is going to be my daily driver, I need heat almost right away in Winter. If you happen to remember who had those kits please PM me. I will go check the Classifieds now to see if I can find them.