naterrt Report post Posted August 1, 2019 Hi. I've been learning a lot about my aqua hot system from your forum. I recently acquired my new to me 1996 Hawkins motorcoach with the older aqua hot model 413/12. It would originally would run between 15 and 30 minutes then stop. I I serviced it with a new fuel nozel and filter. I have not run it because I needed to drain the old boiler antifreeze, it was in bad shape. I'm hoping someone can help me with a couple of questions. I understand the zone bleeding procedure from the manual but need to get an air blow gun to pressurize the system. Question#1, Do I fill the tank completely with new antifreeze? My manual says 15 gallons then start bleeding procedure. It has 15 gallons in it but is not "full". Question#2, can I use the domestic hot water safely before bleeding the heat zones? Also, I keep reading to mix the antifreeze 50/50. I purchased the camco boiler antifreeze that says "no mixing required" Can anyone clarify? Thanks. Share this post Link to post Share on other sites
jleamont Report post Posted August 2, 2019 naterrt, Welcome to the FMCA forums! You can run the system with the domestic water loop drained or winterized, I wouldn't run the unit without the unit without the heat zones completely bleed out. I would fear the pumps would be running with no solution in them and damage the pumps. Since you are converting over to "boiler antifreeze" from traditional automotive ethylene glycol make sure all of the system is completely drained including each heat register and the wall tubing supplying the heat registers. You could accomplish this by blowing compressed air through out the loop, just be sure to keep the pressure low, id say below 10 PSI unless you locate a spec that states otherwise. Finally, YES, that product is premixed and you do not need to add water. When I replaced the fluid in ours I vacuum filled the system with a tool similar to this one, I did not convert it to the new Boiler fluid you have pictured above. https://www.grainger.com/product/45PG67?gclid=EAIaIQobChMIup-Q8oTk4wIVhJ6fCh2zzweFEAQYAyABEgJtNPD_BwE&cm_mmc=PPC:+Google+PLA&ef_id=EAIaIQobChMIup-Q8oTk4wIVhJ6fCh2zzweFEAQYAyABEgJtNPD_BwE:G:s&s_kwcid=AL!2966!3!50916716037!!!g!82496524917! Share this post Link to post Share on other sites
naterrt Report post Posted August 3, 2019 I followed your advice and it's working now....... But I have a antifreeze leak in my middle heat zone. I don't need heat now as it has been extremely hot here. Can I shut the furnace sections off while I determine the best way to reach the leak. I need the hot water, I have 3 small kids. Thanks Share this post Link to post Share on other sites
jleamont Report post Posted August 4, 2019 Yes. If you run on diesel it will circulate through one zone automatically, but the fan doesn’t come on unless the wall thermostat in that zone calls for it (toilet room in our coach) on electric no heat circulation. FYI those are 5/8 heater hose that feeds the registers within the cabin area, nothing special. Very simple system on that side. Share this post Link to post Share on other sites
