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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Forrest on November 02, 2006, 08:54:45 PM

Title: Proheat configuration
Post by: Forrest on November 02, 2006, 08:54:45 PM
I am installing a Proheat X45.  For now I will just implement interior heat loop with toe-kicks.
I understand basics of how to do this but am unclear about t-stat control.  I would like to end up with the ability to control temp in two locations:  front living/kitchen and back bath/bedroom.  Ideally, I would have a t-stat in each location and somehow wire so if either wants heat the Proheat fires up.  If I build just one loop as planned, the section that is not being heated will simply not have the toe-kicks turned on.  Coolant would still circulate and any heat 'lost' in this way would just take the edge off in the unheated space.  Seems like I would want t-stat control on the Proheat, but maybe also on the toe-kicks.  Can't quite picture how that would work.  These systems have been installed lots of times, so somebody knows a good way to do this.  I should mention I got the price sheet from Wrico for their $5k Webasto system and have decided on used Proheat.  The Wrico sheet has something called 4 zone diode board which I assume is intended to allow up to 4 t-stats to be wired through it to control Webasto.  Don't know if it would work with Proheat.
Another question is where to locate Proheat.  My inclination is back bay:  it is clean there, any heat escaping would be welcome in the bay, don't see an obvious place in engine compartment.  Don't know how noisy unit is.  If it is noisy, I guess under sleeping area might not be great idea.
Thanks for all suggestions. :-\

Title: Re: Proheat configuration
Post by: Homegrowndiesel on November 02, 2006, 11:59:31 PM
Hey Forrest

Sounds like you have a good handle on it. ;)

I wired my system with the breaker as my heat on off switch.
Off the switch leg I ran 3 wires.
#1 to the diesel boiler energize lead. (not main power lead)
#2 to the bedroom thermostat, and through tstat on to the hydronic fan coil.
#3 went to the living area thermostat and toe kick.

Wired this way when we need heat we turn the heat switch on and the boiler heats the system, and the tstats maintain the temps in the seperate areas.  8)
The boiler will cycle on and off as needed to maintain heat within the system.

Yes you can use  diodes so you do not energise all circuits at once.  :-\But as you mentioned just by running the boiler and circulating the hot water helps take the chill off and the toe kick fans realy boost the heat when you need it. I always turn the heat off when not needed anyway, so I didn't use diodes.

I also added potable hot water and baseboard heat with a couple of circulation pumps controlled by the tstats also, much more even heat and added convenience. ;D

Put the boiler in the wet bay
If I had heard one run I would not have put mine in the engine bay, and the heat in the wet bay is a bonus.
Good luck with your choices.


Title: Re: Proheat configuration
Post by: DrivingMissLazy on November 03, 2006, 05:15:19 AM
I had four thermostats. One that I kept at about 72 for the Webasto itself. It always had to be turned up to get heat anywhere. Then there were individual thermostats for each area to provide even heat where needed and controlling toe kick units. One up near the drivers area, One in the dining area that controlled two heaters, one in the bath room and one in the bedroom. Thermostast were adjusted as necessary to provide the proper amount of heat in each area. Worked great.

Title: Re: Proheat configuration
Post by: Jerry Liebler on November 03, 2006, 06:28:58 AM
      Since it's a direct current system you can use diodes to 'or' together the outputs of multuple thermostats and actuate the boiler with the result.  The thermostats aren't rated to carry the current of the fans in the toekicks so you should add relays.   Also you really don't want the fans in the toe kicks turning on untill the coolant is warmed up.  The usual way of delaying the fan turn on until the coolant is warm is to use a normally open aquastat (about 120 degree) to sense the coolant temperature.  This aquastat is in series with the ground side of all the toekick fan relays.  I found that I could mount my Webasto above the transmission in the engine compartment.  I use one thermostat in the bedroom to control fan coils in the bedroom and bathroom. and a second thermostat, on the dinette wall to control the front fans.  I also have a zone controlled by an aquastat in the domestic hot water tank.  My system is actually one of the Wirco kits that I bought from a busnut who gave up on his project. 
Jerry 4107 1120

Title: Re: Proheat configuration
Post by: DrivingMissLazy on November 03, 2006, 06:43:15 AM
The reason for the seperate thermostat for the heater is that it was also used to pre-heat the engine and the hot water tank. Probably not really necessary though, with the setup that Jerry described.

Title: Re: Proheat configuration
Post by: RJ on November 03, 2006, 10:19:36 PM

  I found that I could mount my Webasto above the transmission in the engine compartment.

Jerry -

Did you mount the Webasto in front of the engine bulkhead, where the old restroom holding tank used to be?

Or is it in the engine compartment itself, above the transmission's mousetrap?

Thanks. . .


Title: Re: Proheat configuration
Post by: donnreeves on November 04, 2006, 04:35:49 AM
 I am using the X45 Pro-heat and control it using standard house type Honeywell zone valves. These valves wire directly to the themostats and have a built in relay that switches the boiler on and off.The problelem with them is that they operate on 24VAC, so a transformer is needed tp convert 120VAC to 24VAC the relay dosn't care that it's handling 12VDC.It sounds like an energy hog, but isn't. The advantage to them is that they are availible everywhere, should a problem arise.I ran the system 24/7 last winter and had no problems.Zone valves also control domestic hot water and engine pre-heat.The system is fully automatic.Nothing to do but flip on the power switch, and set the thermostat.If a componet fails it can be run manually.

Title: Re: Proheat configuration
Post by: belfert on November 04, 2006, 08:14:03 AM
Donn, does the Proheat have seperate boiler control and power controls, or is your power switch for the entire system?  I got my Proheat several months ago and have yet to do anything with it.  (It will be a winter project I think.)  I probably need to do a complete service on mine including nozzles and such.

I really like your idea with the zone valves and the relays.  I'm probably going to steal your idea for my heat system.

Does anyone know where to get parts for the Proheat, or do I just contact Teleflex Power Systems directly?  Cummins NPower used to carry the parts, but no longer.

Brian Elfert

Title: Re: Proheat configuration
Post by: Homegrowndiesel on November 04, 2006, 08:19:23 AM
 ???I forgot to mention that I used line voltage electric baseboard thermostats, simple, reliable inexpensive. :)  

For a simple setup, No need for a thermostat on the proheat, The Proheat has a built in aquastat to automatically maintain 160-180 degree coolant temp. Of course the premium setup is to use a diode board and have the boiler on an main thermostat.