Here is a write up for our Hydronic Heating modifications. Note that all original functions that our View came with from the factory are still in place and functional (Furnace/water heater/etc).
I really did two different modifications to produce heat - Water Heater Hydronic Heat and Espar Hydronic Heat.
I'll do the write up in two posts.
Espar Hydronic Heat Steps:
-- Completed the modification to allow the Espar heater to run without the engine being on and for an unlimited amount of time. http://sprinter-source.com/forum/showthread.php?t=668&highlight=espar+relay
-- Modified the Espar wiring to be run from the Coach's batteries. Tip: you need to modify both the "espar mod" battery connections and the fuse under the drivers seat (25 amp).
-- Added switch (Aquahot switch panel - ELE-ASM-506) to the control wall in order to control the Espar (on/off) which is also controlled by the electronic thermostat controller (will use this feature to heat the water heater in spring/fall/etc). Ran wiring back to control wall from dash to control Espar and another wire to control the dash fans (on/off - controlled by thermostat).
-- Ran Goodyear 5/8 Hi-miler heater hose from the output of the Espar (used a 1" x 1" x 3/4" pex T) under the chassis to the water heater's motor aide connections and back to the engine with the connection right below the dash heater valve (used a 1" x 1" x 3/4" pex T).
-- Installed a Cozy III (EXE-103-0EX?) heat exchanger under the pantry and ran the heater hose to this heat exchanger.
-- Tapped into the thermostat's heat pump wiring and added relay to control the switches on the control wall.
-- Added switch to the control wall to control the Cozy III (high/low/off) and to control the dash fans (on/off).
Steps to run Espar Hydronic Heat:
-- Ensure that the electronic thermostat controller is set to above 160 degrees before it will turn off. The Espar will run continuously as it takes too long to "reheat" the engine if you had the Espar turn off/on with the coach's thermostat. The Espar only uses .07 gph on low speed.
-- Turn on the Espar switch on the control wall.
-- Turn on the coach's thermostat to the Heat Pump option. The bonus with using the Heat Pump option is that if for some reason the Espar Hydronic Heat can not keep up with the demand, the thermostat will automatically turn on the LP Furnace if the thermostat's temp setting and the actual temperature is 4 degrees or more different.
-- The Cozy III heat exchanger fans will be controlled by the coach's thermostat.
-- If cold enough, turn on the Dash fans via the switch on the control wall (controlled by the coach's thermostat).
The Espar will heat the engine to 180 degrees and then it will go to a low speed or idle state. The engines electric coolant pump will circulate the coolant back to the Cozy III and the water heaters heat exchanger. The heat exchanger will produce great heat and the water heater will slowly heat up.
The Cozy III fans and the dash fans will cycle on/off via the control of the thermostat. When the thermostat calls for heat, the fans will turn on (blow through Cozy III heat exchangers) and when the coach has reached the proper temperature the fans will turn off. The Espar will continue to run and the water heater will continue to be heated via the Espar.
The Espar will slowly heat the water heater. That water is then circulated through a loop in the hot and cold water piping in the coach. There is a check valve under the kitchen sink to allow for this loop. This feature will keep the pipes from freezing. The pipes will also be protected via the cold air return that is below the shower. The Cozy III's will draw air through that vent, under shower, piping in rear of coach, and to the water pump area.