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Mobile RV Repair Service – Port Angeles Area

Certified Mobile RV Technician, Darren Koepp, takes you along as he changes the heat pumps on an AquaHot 450D on-demand RV water heater.

If you are in need of RV Repairs in the Olympic Peninsula area of Washington state, submit a service request on our website at today!

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  1. Milwaukee makes a new pump and you really should get one for the stuff you do. The pump is cordless.

  2. Hi Darren: My Coach is in the Richmond Va. Area. I have been trouble shooting my Aqua Hot 450 DE2 for over a month with no success. The burner will not ignite. I know you can’t do s service call in person, but are you willing to guide my through by facetime? I will gladly pay your normal visit fees. [email protected]

  3. my zone 1 ( main area) only blows cold air zone 2 works great hot water works great was told to tap on check valve might be stuck tried it no difference checked pumps ( by feeling water flow/ vibration) both pumps working. zone 2 line hot, zone 1 cold. called a local mobile tech the other day ( it was 21 degrees here in florida) we were in a campground, he came and checked said pumps ok, check valve ok but seems like blockage from return line from heat exchangers charged me $ 300 said it would need to go to factory to fix ….coach is a tiffin 45, red bay al along way to go any ideas?? where are heat exchangers located ? does this seem right ?

  4. Very good, detailed video. My coach is 7 months old and has the old style pumps, but they are working(I checked voltage on both and isolated #1 and can feel/hear it running. Lights are sll green). I am not getting heat in zone 1. Zone 2 works fine. The line from Aquahot to check valve is hot, but between check valve and pump remains cool. From the pump 1 to zone 1 is cool also. Is it possible to have a faulty check valve on a new coach? Or should I be looking elsewhere for the problem? I’d rather DIY than drive it to get service. Cold and snowing here. Thanks!

  5. Thanks for the vid…new aquahot owner here and the vid was helpfull to learn what makes aquahot tick!

  6. Hey, I’m helping my cousin work on his aqua hot 450D. He’s needing the pumps like you replaced in this video. Been looking for the part numbers but haven’t seen them yet. Can you get me a link for them. Thanks

  7. Very happy I found this video. I have the same system, a 450D, and the front furnace isn’t blowing hot air. Of the two lines exiting the Aquahot, only one is hot. So I thought it was a pump issue and this video confirms it. Now I know how to definitively troubleshoot and fix it. Thank you!

  8. Very helpful Darren, thanks.. I had to change both of my pumps out as well. 2016 Entegra Anthem.

  9. Darren, quick question.. do you remember what year this aqua hot was. I have the exact same system in my Entegra, and was curious when aqua hot made that change away from the faulty motors. Mine is a 2016. Thanks in advance!

  10. Great video with nice, clear instructions. Had to do my own two pumps (Like those) one year apart with the retro kits.

  11. I am so glad I found this video, I had this exact problem when my 450d would make hot water and no heat. It was 25f outside when it failed. I called the folks at Aqua Hot and they helped me troubleshoot the system and bypass the command circuit in the coach, the pumps were good but the circuit board just got stupid. After I jumped the signals the system started working and hasn’t failed again. Go Figure. It was great to find a video explaining what the components are and where they are located.

  12. Your site and information is so very useful! This is exactly what I needed Darren – thanks so much! Now the RV Sales Company cant find the replacement part – they do see there is a new one to replace this (but didn’t know anything about the kit. Aquahot isn’t the easiest site to navigate and forget calling on the phone. Do you have the kit numbers? I figured since pump 2 is out I should probably replace both pumps while I am doing this! (thoughts on doing that?

  13. You could hear my pump working but no fan blowing inside. I did bypass the fans and they are working…what do you think?

  14. Thank you I work on these but have not had to do a pump but now I do .one came in to the job so just want to say thanks for the helped me understand the I will work on it comfortably

  15. Thanks so so much. Is hydro hot the same I think that’s what I have and I want to service it. I need to go look hehe. Thanks alot

  16. Very interesting. So on the inlet side of the pump there is a rubber hose that connects into a metal fitting on the wall. Is that a check valve?

    Aqua hot seems to have engineered as if none of the parts will ever break. No valves to isolate the pumps from the system and jury-rigging the door switch seems like they really cheaped out.

  17. You are supposed to drill holes for the pump or the cover will chaff the wiring on back of the pump. That bracket is for the stir pump which has already been replaced. Also, nice dipping the hose in the antifreeze but put the pump in there as well to make sure it is lubed and not dry.

  18. I appreciate this vid. I have a 450D and 1 zone has stopped pumping. I have not trouble shot it yet. Just assume bad pump. My Aqua Hot is 2010 vintage. I access the burner/pump from passenger side and the display board and expansion tank from the driver side LOL

  19. Darren, when watching the video I noticed that the antifreeze looked like automotive antifreeze. My understanding is you should use a non-toxic, I forgot the kind of antifreeze it is, but because the domestic hot water runs through the boiler, cross contamination could happen. If this is not the correct, please advise, Thanks, Enjoy all your videos and have learn a lot.

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