[Mirra]

Looking for feedback on the ministry defender heat/ ac combo unit. Kit is complete and includes all hoses and fittings? Are you happy with the quality and the output of the ac temperature?
I’ve been using a webasto diesel heater these past winters, but may remove that system in favor of this ministry kit. Feedback welcome….:thanks, Jim

 

[Z.G]

As far as I know, the MoD kit still requires coolant temp to be hot to produce heat, incomparable to a webasto diesel heater. Im guessing they can be used in conjunction for a better solution.

The 300tdi just doesnt produce much heat in the colder months in the northeast

 

[Ephry73]

A radiator muff helps a LOT but you can always try a different heat exchanger.

 

[Overlander]

I have installed mine, but haven't finished the AC hoses yet. Had the heater up and running at end of winter this year, and it was fantastic heat for my 300 tdi 110. Even if it was the same capacity, the fact that it pulls air from the cabin instead of external means it has a compounding effect. Expect the same with AC. And I don't give up any front knee space for an under dash unit. no regrets so far.

 

[KGH]

Mark, did it fog up with wet/snowy boots and such?

 

[Red90]

Yes. You can’t only recirculate air in the winter. The humidity will keep increasing until the windows fog up. It is just a plain fact of science. You need to bring in fresh air to keep it below the dew point at the window temperature.

 

[Red90]

I'll add that I don't have first hand knowledge of this HVAC system. But the fact that they designed it without a fresh air intake (which would be easy to add), shows me that the designers do not know what they are doing.

 

[Red90]

The 300tdi just doesnt produce much heat in the colder months in the northeast

This is not true. The engines produce enough heat. The stock matrix is not a bad size, but is not very efficient. This results in a high approach temperature (difference between coolant and heated air temp). A better matrix helps a fair amount in reducing the approach. I use a heater than has been measured to output 2.5 times the heat as the stock heater so it clearly is not an engine limitation.

Beyond the heater efficiency, the biggest issues with heating a Defender is air leaks and insulation. Fixing those issues is a critical first step.

 

[Z.G]

This is not true. The engines produce enough heat.

I watch my temp needle drop to 25% when not under load, it definitely doesn't produce enough heat when it's sub 30s. That's with a radiator muff

I will say the larger issue is sealing the cab, it was much more livable in the tdi Disco than it has been in any tdi defender I've been in

 

[Red90]

I watch my temp needle drop to 25% when not under load, it definitely doesn't produce enough heat when it's sub 30s. That's with a radiator muff

I will say the larger issue is sealing the cab, it was much more livable in the tdi Disco than it has been in any tdi defender I've been in

I drive down to -40 with a heater than has 2.5 times the heat output as stock and it will cook you alive. The air burns your leg. No radiator muff. Radiator muffs are bandaids for leaking thermostats.

 

[Red90]

From last winter.

That is -24F outside and 63 F inside. After a 15 minute drive.

 

[Overlander]

Mark, did it fog up with wet/snowy boots and such?

no, but it might until I finish the install. Once complete, it designed to run the AC and heater at same time as a deliberate function, with the AC being a dehumidifier for the cabin. It's specifically addressed in the manual.

 

[Red90]

no, but it might until I finish the install. Once complete, it designed to run the AC and heater at same time as a deliberate function, with the AC being a dehumidifier for the cabin. It's specifically addressed in the manual.

You can't run the AC in the winter to dehumidify. The evaporator would plug up with ice quickly. You can probably get away with it in teh UK, where it does not get cold, but anywhere with actual winter, you are screwed.

 

[KGH]

Can of worms thread!! But very interesting.

And living in the snow belt, relevant to my decision making process.

 

[Overlander]

Regardless, I'm committed and love the system so far. We did have one day at end of winter here in Charlotte that was very cold and wet (feb-mar). My windows fogged up quite a lot, but I was able to blast them clear with defrost heat from the MoD system (which blows very strong) in about 2 minutes. I'm just sharing my experience so far, not trying to debate anyone's experience or theories. I'll report out on findings this winter when get up in altitude for some winter, snow trips.

 

[Mirra]

Regardless, I'm committed and love the system so far. We did have one day at end of winter here in Charlotte that was very cold and wet (feb-mar). My windows fogged up quite a lot, but I was able to blast them clear with defrost heat from the MoD system (which blows very strong) in about 2 minutes. I'm just sharing my experience so far, not trying to debate anyone's experience or theories. I'll report out on findings this winter when get up in altitude for some winter, snow trips.

View attachment 478767

How long did it take to install the mod system?

 

[John Z]

Install is about a day. I was able to knock it out within 8 hours.

As for the windows fogging, I did have issues with it last year, but then again my thermostat was stuck open so the truck wouldn't warm up. Now I have a new thermostat so I actually get to 180/185. I picked up a heated windscreen which is amazing. I'll update how this year goes

 

[Red90]

Personally, I would construct a fresh air flap. Connect it to the fan speed cable so that you can open and close it. That solves the winter issue. I have no idea why they don't do this with the original design.

 

[John Z]

Personally, I would construct a fresh air flap. Connect it to the fan speed cable so that you can open and close it. That solves the winter issue. I have no idea why they don't do this with the original design.

When you swap to their fan setup you don't use the factory switch that uses the cable. I guess in theory with my setup I could make it work.. I'll have to keep an eye out for another heater switch with cable since I sent mine to the bin.

 

[Ephry73]

A better core and a fully and correctly working engine cooling system are key. Oh my 97 wrangler which has no insulation inside or carpeting and runs a canvas top year round I can get pretty toasty in the winter after five minutes of highway driving.