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Anyone using the ministry defender heat/hvac kit

3112 Views 48 Replies 16 Participants Last post by  Red90
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
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At this exact moment, I’m not impressed with my MoD unit at all.

Just had it vacuumed and recharged.

It takes 10 degrees farenheit off the input/ambient temperature (91 degrees at the footwell becomes 81 degrees at the vent).

I’ve double and triple checked that there is no coolant leaking through the system too.

And now the condenser fan remains on for at least 10 minutes after I shut the truck off.

Not super thrilled with it.
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Has the vendor provided any solutions ?
I emailed them last night, I’ll update you when I hear back.

I’ve emailed them twice before, and both times they respond quickly and answer my questions (one was about an extra inline fuse that my mechanic installed… )
I think I figured out one of my issues.

I checked the vent temperature again today. After 1-2 minutes I was super excited because the vents were showing about 22 degrees Fahrenheit cooler then the footwell/ambient… but after about 5 minutes it went back 10 degrees difference (the cold air warmed up!)

I checked the coolant control valve for the 4th time (not leaking).

BUT, I discovered the one way valve on the outflow water line for the heater core had a healthy leak. It was allowing retrograde flow of hot coolant into the heater… warming the air up.

I just wanted to update, I’m very hopeful I will get some much better performance once I get the one way valve sorted out.

I’ll let you know what the vendor recommends.
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I’d be incredibly happy with 40s-50s at the vent!

I heard back from MoD first thing this morning. Very fast response.

They are sending out a new one way valve, and a new relay (for the fan staying on after the truck is shut off).
This morning I removed the heater lines from the unit, and it’s blowing as cold as I would expect now. The poorer performance was definitely related to a faulty one-way valve.

Ambient temp of 71 degrees and the temp at the vent got to 49.6 degrees… so taking about 20 degrees off (which I am happy with).

My observation though is that you have to be travelling at speed to get this temp. If you are just sat idling (with the condenser fan running), it will only take 10ish degrees off ambient.

If it is 90 degrees out I’ll expect 70 degree output at the vent… if it’s 110 degrees out, I’ll take Range Rover Classic😉

I’m happy with it again. I could make the cabin a lot easier for it to cool by tinting the glass and adding some insulation and a headliner… but I’ll leave those to the next owner.

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