Let's talk about heat...

[Pete Masterson]

I have a '95 [PT]42 diagonal aisle -- all electric (no LP gas). I
have the AquaHot 431 for heat and domestic hot water.

I'm trying to wrap my brain around the various controls:

I have 3 Dometic thermostats located in the bedroom (rear), in the
center and above the driver. These operate the three AC units when
set to "AC" and (apparently) operate the Aquahot heat when set to "GAS".

The rear thermostat works as expected and heat blows out from both
sides behind the (side island) bed. The fan that moves the heat is
barely audible.

The center thermostat operates a radiator beneath the kitchen
cabinets and another one beneath one of the sofas toward the front.
The fan for the radiator beneath the kitchen cabinets sounds like a
jet taking off ... but (thankfully) the one under the sofa is barely
audible.

Now here's where it gets interesting. The thermostat above the driver
doesn't seem to do much, if anything, with the heat. There appears to
be a radiator in the dashboard area and a very gentle bit of heat
comes out. If a fan is running, I can't hear it. I would expect this
heat would be controlled by the front thermostat, but it seems to
work in connection with the center one. (I haven't had the
opportunity to experiment more fully.) Of course, if the center heat
is on, the loud fan from under the kitchen cabinets drowns out any
fan noise from the other fans (making it hard to detect from sound
alone which is working). Question: Is there any way to adjust the fan
speed and/or make it quieter? (the fan speed switch on the thermostat
has no effect).

Finally, the AquaHot has radiators and fans in the basement with a
"cold" thermostat that allows setting the temperature as low as 40
degrees. If the thermostats in the "upstairs" are all off, then the
fans come on, but I didn't detect any heat (perhaps I didn't wait
long enough). Does the basement heat work independently of the other
heat?

In addition, I have 3 thermostats (square-shaped) that control
electric heat. Two of the electric heaters are in the bathroom with
two thermostats. This is convenient as you can make the bathroom
rather toasty during a shower and you can also select the heater that
doesn't burn your feet depending on where you're standing in the
bathroom.

The third thermostat is right next to the Dometic one in the center
of the coach. When a switch is set to "cool" it operates the roof
mounted ventilator fan. When the switch is set to "heat" there's a
loud "click" but nothing happens. I can see a grill similar to those
in the bathroom for an electric heater under the kitchen cabinets --
I presume this is an electric heater like those in the bathroom, but
it apparently isn't working. (What kind of heater is this? Where can
I get parts or replacements?)

In addition, there is, apparently a chassis heating system that's
controlled by the same controller that operates the chassis AC. It
blows out warm air through the same vents that the chassis AC uses. I
don't know if it provides heat elsewhere in the coach.

There is a switch on the dashboard called "hydronic heat" -- I have
this switch on (since I want the heat to work) -- but what, exactly,
does it do? Will the Aquahot work with it off? Or, does this use heat
from the engine?

Lastly, the Aquahot burner (runs on diesel) doesn't come on
consistently with the arrival of heat. Is there an electric heating
element as well? Does this provide initial/low heat levels?

Any help with these questions will be appreciated. (I've spent time
with the blue box --- but it's very general and isn't very specific
about the heating system.) We're in the midst of a "cold snap" where
the lows have been around 28 (highs in mid 50s) ... so I want to be
sure that nothing will freeze up, so I've got the heat on in the
bedroom at 50 degrees or so and the basement does seem warmer than
the outside air in the morning. The coach also has 30 Amps of shore
power (keeping the batteries up) in its present state.

Pete Masterson
aeonix1@...
'95 Blue Bird Wanderlodge WBDA 42'
El Sobrante, CA






[Non-text portions of this message have been removed]