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Rig Master APU Install
RigMaster, a Canadian company had its ups and downs,
when it finally went under one of it's suppliers was left holding the
bag on a lot of expensive custom components. They acquired the assets of
Rigmaster and resurrected the company. Hopefully they will succeed.
Rather than scratch build we found the Rigmaster filled the bill.
What makes the Rigmaster unique among truck APU's is that other than 12V and a diesel fuel supply, it is completely autonomous. It is not parasitic to the truck's coolant, it is not plumbed into the air conditioning or heating circuits. Most APU's put out gobs of 12VDC and then to give you 120VAC you pull it from your batteries via a large inverter. Lots of efficiency losses that route.
Rigmaster's AC generator gives you two honest to god 20A/120VAC circuits, plus a 60A DC alternator to keep the truck's batteries happy.
The under the bunk A/C evaporator/heater is fairly compact and can be ducted as stand alone. As shown below we chose to use the existing rear cab A/C ducting via a custom fabricated Y duct and a custom return duct that uses Volvo HEPA filter elements the same as the Volvo rear bunk system does. To prevent recirculation through either system, one slot has a filter in it, the other has a dummy block off filter in it. To switch systems one only has to lift the seat and swap filter positions.
Craigslist provided well for us once again. We found a unit within a days drive and some strong backs to assist us in loading the 400 lb beast.
We gave it a quick once over when we first arrived
and it seemed in good shape. At the price it was a good risk.
We acquired all new filters, belts and a replacement
flexible coupling for the exhaust. We also ordered an alternative
mounting bracket. It turned out the previous owner of our Volvo also had
a Rigmaster in it and took it with him to his new truck.
Bunk Unit Install
The Rigmaster comes with a single 4" round outlet you
mount down behind your knees and they expect you to rotate it down when
heating and up when cooling. Neither seemed optimal to us.
The APU itself clamps to the truck frame, no holes
Two things we wish to improve upon are the exhaust system and the noise level. These small 2 cyl diesels are bone crushers, sounds like a jackhammer if not handled properly. While this would be fine in a truck stop or rest area it would be downright un-neighborly in a campground and would result in you being run out of the place if you insisted on running it. I do not know if we will be able to make it quiet enough for campground standards but hookups would be available in most campgrounds. Our only large loads will be the microwave and a mini-split A/C system.
We will be mounting the APU to the chassis soon, stay tuned!