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rhagfo's avatar
rhagfo
Explorer III
Jan 02, 2017

My Cheap Heat install

Well decided to go with the "Cheap Heat" system in our 5th wheel.
I did the install as a DYI, have done enough electrical work to feel comfortable with the high voltage work.
I read all the documents on line and the clearance needs, well I new it would be a snug fit.
I ordered the kit which is very complete with exceiption of the high voltage parts. I spent about another $150 for the necessary high voltage parts, and other needs.
This is the major parts I bought;
Square D QO 30 amp disconnect cabinet
Square D QO 30 amp breaker
Ground bar for 30 amp disconnect
Square D Home line 20 amp single breaker
15' coil of 10/3 with ground wire
25' coil of 10/2 with ground wire
2'X4' piece of heave sheet metal (I needed to extend the duct a bit).
The instructions are very clear and complete, I have it rigged so that in Spring, Summer, and Fall if 50 amp service is not available I can changeover to operate on a 30 amp shore connection. This would take about 10 minutes to move some of the line voltage connections.
I found even though I had improved the seal between the furnace and floor once the install was done the furnace worked better, with better air flow on gas. This was due to the old design the hot air really didn't have good air flow over the heat exchanger it only partly passed over it before going down into the duct.

So we are Currently dealing with temps in the high 20's at night and the 5,000 watt (17,060 btu) output is keeping us at 68 degrees.

This is the furnace under the sink location with a home fabricated 3" duct extension between the OEM furnace and Cheap Heat exchanger.


This is the 3" duct I built out of heavy sheet metal, would have been nice to have a sheet metal brake!



This is the 30 amp disconnect and the control box.



The best part of all the Gas / Electric switch!


Sorry for any typos and weird typing posted from my iPhone.
  • I posted this earlier but it disappeared. Am I correct that you are using 42 amps to run your heater? i.e. 21 amps on each leg?
  • Hi,

    The 1800 watts is one of my objections to the system. 1500 would be so much more useful.
  • rhagfo's avatar
    rhagfo
    Explorer III
    Cummins12V98 wrote:
    "running 5,000 watt setting (17,060 btu) and staying warm."

    Is there more than one setting? I know nothing of this.


    The systems has three possable wattage setting, settings are;
    1,800 watts, 120 volts, 20 amp.
    3,750 watts, 240 volts, 20 amp.
    5,000 watts, 240 volts, 30 amp.

    Yours is most likely set at 5,000 watts based on size of your rig. I have a 240 volt 30 amp setup, but also have a provision to run it on a 30 amp power post, to set back to the 1,800 watt setting. It will require moving a couple connections, moving the controller box to a 120 V, 20 amp breaker, and at the heating element down to the 1,800 watt connection.
    I am sure the 1,800 watt setting will do fine in the summer, and likely late spring and early fall.
    It is part of the beauty of the system, one kit that can be configured three differnt ways.
  • "running 5,000 watt setting (17,060 btu) and staying warm."

    Is there more than one setting? I know nothing of this.
  • rhagfo's avatar
    rhagfo
    Explorer III
    Well still enjoying the warmth of our Cheap Heat system out on the Oregon Coast. Currently on a 50 amp connection so running 5,000 watt setting (17,060 btu) and staying warm.
    I stated earlier that after getting the unit installed and testing gas operation that I noticed a much improved operation. This was both better air flow and the air out of the duct seemed warmer. I believe this is due to two things;
    1. Better sealing of the duct system. While I had made improvements in the sealing before, the end cover was not sealed with duct tape, I have always used the foil type for HVAC work.

    2. Better air flow over the gas heat exchanger. Before the install the air flow went down towards the end of the heat exchanger box so the air didn't full pass over the surface of the exchanger.

    This is a drawing of the difference in air flow of the Old and New setups. Yes, the system is NOT cheap to purchase at $545 for the kit and about $150 in electrical parts for the line voltage part, but going into full timing using far less propane and better heat on both it is worth it.

  • rhagfo's avatar
    rhagfo
    Explorer III
    pianotuna wrote:
    Hi,

    What was the time required to do the DIY?



    Sorry I missed this question.

    I worked for about an hour and a half to make the 3" duct extension it would have been about 20 minute if I had access to a sheet metal brake.

    The install in the trailer took about four hours to get the wiring pulled and connected, 10 gauge wire in somewhat tight spaces is not real easy.

    Needed to cut and secure covers for the old openings for connection to the duct from the furnace. Then needed to cut new openings through floor and duct to drop the new plenum into.

    The last item to do was placing the switch, I wanted it next to the t-stat. We currently don't have a sealed under belly, so it was an easy job of hitting a 1" space between the cross member and water tank support with the cable. The cable included with the kit is about 20' long and was easily long enough to get to near the furnace for connections.
    To make dealing with the connections at the furnace easer in the future I installed a terminal strip.
    I will say totally impressed with the quality and construction of the product!
  • rhagfo's avatar
    rhagfo
    Explorer III
    pianotuna wrote:
    Hi,

    Consider adding a fail over relay so if power is lost the furnace will default to propane.

    Add a switch to go from the 50 amp 240 volt configuration to the 30 amp 120 volt wiring.

    What was the time required to do the DIY?

    May I ask what the total cost was?


    I am engineering the fail over for the gas electric issue. Just trying to decide if I want to use line voltage relay or 12 volt relay powered by a transformer.
    The 50 to 30 amp requires changing the input voltage to the control box AND changing the connection at the heating coil, for as often as I would do it just easier to move the wires.
    Total cost with the kit and extras was just over $700, I love it as we have to very active beagles and the though of them knocking over a space heater, and the fact that this is controlled by the thermostat means nice even heat.
  • Hi,

    Consider adding a fail over relay so if power is lost the furnace will default to propane.

    Add a switch to go from the 50 amp 240 volt configuration to the 30 amp 120 volt wiring.

    What was the time required to do the DIY?

    May I ask what the total cost was?

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