Sail Life - Dometic Proheat X30 hydronic heater on a boat, part 1 of 3 - DIY project

Publicerades den 6 dec 2020
It's getting colder by the day! I need some heat! This week I get started installing a Proheat x30 (
If you want to order Christmas gifts from and be sure they arrive in time these are the dates to be aware of :)
US - December 10
Europe - December 6
00:00 Introduction
00:09 Dometic Proheat X30 and other components of the system
01:40 Insulating the hull
02:27 Plumming diagram
06:18 Technical compartment
07:03 Location for Proheat X30
11:54 Layout of the technical compartment
12:50 Installing two fan heaters (Real Heat 6000 & 6400)
15:19 Where should I install the exhaust thru-hull?
17:02 Cya! :)
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  • Getting waste heat from generator is admirable, however, when generator isn't running it will not add heat. The heat exchanger will help with that situation, but you may have a convection loop (water on the generator side, being heated by your hot water boiler, will rise and circulate) losing heat through your generator. If you add to that your motors heat (in the future), same thing applies. There are ways to incorporate those sources in a better way.

  • What happened to the Refleks?

  • Too bad there isn't a heat exchanger in the bulk tank to run the exhaust through to recycle the heat from the exhaust back into the heating system.

  • What happened to the Refleks Stove that you got for Athena some time ago? What were the reasons behind changing to Proheat X30?

  • watched this, now I'm bored. Can you do daily video's or a constant live stream like big brother please

  • I thought you had a refleks stove?

  • Hvad er prisen for den diesel varmer ?? Tak for alle de fine videoer du laver 👍👍

  • She looks so small in the water.

  • We use the same insulation blanket material at the plant i work at. We insulate 550lb steam piping with it.. should be more than enough. It has saved my arms from being severely burned hundreds of times..

  • When you are done you might want to experiment with using higher speed/volume fans on those matrix units. I'm using the same ones (which are made here in Seattle). On the smaller unit I moved to a 120mm fan (with adapter to step down to 92mm) with 150m^3/h (90cfm) which made a big difference in efficiency of the heat exchange. I checked this by measuring input and output coolant temps and watching how heat dissipated across the unit with a thermal camera.

  • @3:35 I don't know why you are being so shy here. Am I missing something? Independently, heat exchangers and hydonic heaters have their pros and cons. But they were made for eachother. As soon as you choose one, shouldn't you also choose the other? Maybe if I had a boat that already had a different heating solution installed, but no water heater, I might try to run the water heater solely off the engine and generator with some sort of heat exchanger without a full hydronic heater system, but that is a different situation. Hydronic system already has several tanks of hot water in it. Wouldn't installing another tank for hot water just be silly? It seems like "non controversial politeness" is, in this case, just a lazy excuse for not explaining something. I can forgive you a million times over for offending me, if you also inform me ;)

    • @5:30 And with a heat exchanger on your generator the efficiency of your offshore bread baking should go up nearly as high as a diesel oven, with one exhaust pipe instead of two. Nice. Why don't the generator and the hydronic system and the engine all the same exhaust through-hull? Giant hole near the backstay with no engineering review was not so clever...

    • I mean, your electic oven running off the diesel generator is maybe a choice that you want to avoid arguing about xD But here, haven't you clearly chosen the most elegant solution for a water heater that runs off diesel? Am I missing something?

  • Can you not combine the heater exhaust with the engine exhaust and put them through one thru-hull?

  • put the exhaust into the cockpit, boom heated cockpit.

  • :)

  • Hi Mads: Exhaust outlets of any description along the sides of vessels is BAD NEWS. Guaranteed at some point a plastic fender will cover them and then the result is spectacular! speaking from many experiences. Commercially for example on Cats they are on the inner sides of the hulls, if not the transom. However, ideally exhausts (never a good idea at sea as water can go back the other way!) exit through a device called a funnel at the top of the vessel. Even then the fumes still cover the vessel and cause sickness. So apart from not being on the hull sides, your other main concern should be so that the fumes enter the living space as little as possible. Try the top of the mast for example!

  • On the outside of the bulwark. You don’t want sea water forcing its way back in.

  • Another great video thanks and get well

  • Here's an idea, take the boat and sail for the tropics :)

  • Unless you can plug it somehow, I'll second the recommendation to put the exhaust towards the centerline on the stern, to protect it from heavy quartering seas.

  • I hope you write a Sail Life vocabulary/dictionary one day. Maybe a video dictionary.

  • Exhaust outlet location: Could you locate it below the dock lines as mentioned, but install a custom made stainless steel shield above the outlet which would redirect the exhaust gasses downwards towards the water line? Maybe even a removable shield that could be used only when docking, and won't impede sailing speed when on passage.This way the dock lines are protected from the heat. Just a thought.

  • The cold gave you a deep, rich radio-announcer voice.

  • Three comments. 1) I installed the similar models of the REAL fan coils (6000 models line) and the fans that cam with them are the weak link. They just do not blow much air. I am currently looking for more powerful fans to get more heat out of the coil. 2) Think about adding a muffler to the exhaust and a silencer to the intake. The exhaust is real loud (think 707). The intake is a high pitched whistle. Now that I have both, the only thing that I hear is the water pump. 3) You might consider using a "GRAS" rated boiler fluid (Generally Considered As Safe) so that if you have any cross contamination between boiler fluid and potable water it will not kill you. I use Peak Sierra based on Propylene Glycol.

  • Hi Mads, you might want to think about suspending the heater with rubber profiles, thusly limiting structure-borne sound transmitting throughout the boat.

  • Hej Mads Kan jeg lokke dig til at smide et link eller info om hvor man kan købe de grønne skumplader som du ofte bruger til diverse ting - har tævet Google gul og blå med alskens søgninger uden held. Tak for god inspiration :) Bh Thomas

  • Glad you are back I thought there was a glitch in the matrix when there was no saillfe video last week ,👍😁

  • Where do the fan heaters get their required air flow to the fan's? Other words fresh air.

  • Do you have vents to let air flow behind the heat vents. So that air circulates.

  • You had created diy heating item why are you not installing that

  • stay well and beware of the zombie minks

  • Great. I hate my Webasto AT 5000 and searching for a good solution. This is a great small heater. Thanks

  • How is the exhaust protected from an ingress of water? Enjoy all the vids.

  • Glad to see all the progress you're making. It's amazing to see your commitment to the project and fun to see all the things you try. It's definitely given me confidence to try slot of new things myself. Hope you'll be fully recovered quicklt from whatever pesky illness you have at the moment so that you can get all the things you need to get done in time! This has turned into one of my all time favourite YT channels, little did I know I was in for a double refit of the same boat but I do think all the changes you've made are for the better. Good luck with the rest!

  • Nice to see you back Mads. Glad you are feeling better. We have a catamaran with a eberspacher would love this system, the advantage of running hoses instead of ducting would save loads of room and the hot water another huge advantage. Trouble is paying for it all... £4000+. Way out of most sailors/cruisers budget

  • I'd put that exhaust on the transom because if you put it on the starboard side you could get alot of water in there.

  • I put my exact in the combing.

  • Glad to see you back Mads. Hope you feel better soon.

  • We have had two heaters on our boats. First exhaust was right where you started, by the docklines. One melted howser on a cold winter's night in Catalina was a lesson learned. The second, on the boat we have now, is on the transom and right above where the dinghy would tie and where feet could get more than toasty! Will be a good challenge to figure that one out.

  • Hopefully you’ll not be anchored out and using the boarding ladder much in the winter when the heater is running, so I say mount the exhaust on the transom.

  • If you can pull the return pipe from the radiator in the bathroom in a loop benieth the floor boards you will get some really nice floor heating in colder climes. We lived aboard our Bavaria 42 in Göteborg during 4 cold winters and we loved that luxuary. Just put som insulation benieth so you dont warm the ocean instead.Took me like 30 min extra and soo worth it!

  • Hey Madds, Have you thought of putting the heater exhaust in place of the through hull is just forward of Athena's dock line and putting that through hull under the dock like. Don't know what is coming out of that forward through hull but thought I'd mention the ideal. Ken.

  • You could install the exhaust in the first location you mentioned, but install some sort of cowling to direct the hot air away from the dock lines.

  • Too complex ,guaranteed to break or require endless maintenance

  • You should have placed the heater module on the centerline, that way it would always be below the expansion tank, even in high seas. As it is, what degree roll will it take and still feed? Is that roll degree likely?

  • I wish the x30 had been available when I installed my X45 several years ago. Except for one small hiccup that the manufacturer covered it has been working flawless for 8 years. I use it also to heat my domestic hot water for bathing and washing dishes instead of engine heat. So we can turn those nice fan coil units off for summer and still have hot water. I also installed heat sensors on the fan coil units so the only start blowing when the water is up to temp. Good luck with your install, it will be one of the most satisfying installations for your boat. Enjoy being warm.

  • Hi Mad's. Good to see you back and recovering. We would go for transom fitting the exhaust outlet and be sure to put a 150mm goose neck in the exhaust hose line just before the outlet. Is it necessary to insulate the tanks also? Sail Safe mate. Ant, Cid & the pooch crew.

  • I hope you feel better soon!!!

  • I have an AMEL 54 and the exhaust is halfway down the hull midship and I didn't think of this until I found one of my fenders melting The exhaust gets very hot so think of a place where fenders are less likely to be. Cheers mate from The BOAT (the best of all things)

  • Is the buffer tank used in 'summer mode'? If so, are you going to insulate it?

  • If you load the storage up, aren't you going to prevent air flow over the exchanger?

  • I love your videos and appreciate the effort you put into them. I am interested in your air supply for your heater fans. Did you leave a vent of some kind so the fans can pull in fresh air? If not you probably should consider that. Keep up the good work and stay safe.

    • The heater fans are intended for heating the interior, so for efficiency they should not be drawing in air from the outside of the boat.

  • merci pour les sous titres

  • Glad you are feeling (a little) better.

  • Get to feeling better, my fellow viking.

  • Mads, good job. Points to consider - a "sealed" system will be easier to vent, have less tendency to sludge, occupy less space as the expansion vessel will only need to be small (4% of the total volume and the pressure variation should be no more than 0.5bar - 2bar). Inhibitor can then be added and basically forgotten about and you'll have no issues with boat movement, frothing/aeration in the vented expansion tank, plus no evaporation and so on, it's normally a no brainer. A temperature and pressure relief valve is all that is then needed discharging to a safe place (I would suggest bilge). I don't know the heater but if it is modulating keep the circulating water as small as possible for response times. The boat, even with insulation is going to be cold but will heat up very quickly so a modulating burner would normally be an important consideration rather than just running the water at a constant temperature. The circulation pipes looked suitably small bore (10mm?) which is great for small volume and response times. Make sure the pump (integrated?) is accessible for servicing. The accumulator tank is a strange one to me but is obviously part of the manufacturers instructions and requirements - follow them. Fit quality isolation valves everywhere for ease of servicing - full bore and temperature rated, butterfly valves save space. Lag pipework where you don't need heat. Heat loss from pipes can be a pain but it will stop condensation and mould in cold climates. As high up on the transom as you can - the exhaust is not designed to mix with water and flue temps should be low-ish (condensing boiler?). A water trap may be required. We have a standard electric water heater and two Eberspaecher which blow very hot gases which means a lagged exhaust, but there are no complaints with the shower and heating! Good luck!

  • If those fans for heaters are a bit noisy, my recommendation would be to check out Noctua fans. They manufacture semi affordable super quite fans for PC. Like Noctua NF-A20 PWM 12V 800RPM 200x30mm

  • Re. exhaust location, couldn't you plug the heater exhaust into the motor engine exhaust?

  • Located near your ladder might not be a bad location as the small amount of heat from the exhaust will keep ice from forming on your ladder. You could put it in the center, shooting between ladder steps to minimize exhaust spooge "nastiness" which ought to be minimal, really. Get well buddy.

  • 👏👏👏👏

  • You're a genius

  • Don’t forget to leave a space behind those fans mas

  • Getting the feeling you’re adding alot of weight Starbard side aft.. not necessarily a problem but the engine is aft aswell, obviously she’s not a racing vessel, but maybe Exaggerates “hobby horse action”. Not sure? You are adding weight mid ship.. so maybe not an issue? Opinions?

  • I hope you read late comments like mine🙂... I found a quite interesting solution for a gimbled stove close to the end of the following ytvid: Hope it helps sage some space👋

  • I was watching this thinking the video quality was great. Then I realised it’s the lighting. You definitely nailed it with the colour temp and spread of lights.

  • Hi Sail-life, Excellent job however I am very surprised to see a rigid mounting of the heater on the hull of the boat, indeed this kind of boiler will tend to vibrate in operation and resonate throughout the hull with the noise of an infernal machine, mounting on silent-block as in submarines would perhaps be wise ...... hello from Françe.

  • We had our heaters blown off when the exhaust was hit by a wave. They were air heaters but O assume they function quite the same speaking about the combustion. Try to develop some cover so the heater can work in rough seas.

  • Hi not sure that metal/rigid plate between the hul and the heater and radiators are the best thing. I would go for some vibration insulation there. Question : Air does exit via fan heater holes you made. WHere does it INTAKE from ?

  • Hope you get feeling better!

  • Pleased you’re back on deck. Hope you stay well and thanks for another great video.

  • Does somebody know the brand of the tubing and connectors Mass is using. I am in the same process of installing a water heater in my boat

    • Normal household pex tubing and connectors. Get from your local hardware store.

  • You could possibly tie the exhaust into the generator exhaust then u wouldn’t have as many holes threw the boat. Just a suggestion but someone out there probably would say it’s unsafe but idk. Love the videos.

  • Glad to see you back, after binging 4 years of your videos in a matter of weeks I was getting withdrawal symptoms! I also hope you dont mind that I gave your overalls their own fame and put them on Things with faces. Love the channel, dang spiffy job!

  • how are you handling air intake for the fan heaters??? those ventilators shouldn't be blocked and usually need a steady supply of air to push through a heating element, don't they?

  • You make fabulous videos Mads. I personally like the side of the boat somewhere. If it's on the transom, you can sometimes get fumes in the cockpit in a following wind, but then you will get that sometime no matter what. Good luck with it all, you're a bloody inspiration. Ciao from western Australia.

  • It's going to be LOUD! Mount it in the engine compartment.

  • How come you're not hooking up the biggest heat source you have on Athena - the engine. In spite of being a sail boat you're very likely to run your engine quite often when going to remote places and just blowing all that energy out with the coolant water is such a waste. Just one more heat exchanger....

  • The biggest problem that happens with hydronic systems is they can be air locked reducing efficiency. Hopefully the expansion tank at a high point will eliminated that problem.

  • When in a marina isn't access to showers usually included in the fee?

  • do you have a carbon monoxide detector?

  • Looks like you have a choice of singed toes or singed line for placement of your exhaust. How hot will the exhaust port actually get? And, how hot will the exhaust be? Personally, I'd go for singed toes as, after actually singing you toes a couple of times, you'll attain the habit of watching where you step if you're just wearing sandals which might not be much of an issue considering where you plan to do the bulk of your sailing. Constantly having to worry about a line failing seems not a good choice. You might even end up with a pleasantly warm boarding ladder - nice for cold days. And, for another Christmasy note - try hot whiskey - it will definitely make you feel better, or at least a little numb to your discomfort.

  • Commenting as I watch :) maybe use some rubber feet as spacers. That might reduce vibrations proliferating from the heater to the hull.

  • Heaters, flu....😳 Get to the Pacific, get warm, get well👌

  • I’ve had a diesel hydronic system, and I installed a Chinese diesel air heater on my newest boat as well. Both made sense to have the exhaust high up on the stern. I think it would have worked just fine on the hull as well, it’s just personal preference. If you have water coming in that high, and up the gooseneck, you probably have a lot more to worry about! I’d go with the stern between the ladder and backstay chainplate. Also, thank you for making such great videos!

  • If the fans are too loud try papst computer fans

  • As you are going to sail with wind in your back, then perhaps not mounting it in the back, as the fumes will pass your head

  • Installing on transom is clean but you have to consider where you will store your dingy and the other things folks hang off the pushpit area during voyages. I think side is best. Move forward of likely route of dock lines by 12 to 18 or so inches and you should not see an issue.

  • Mads, why install the heater in the boat and not on the other side of the bulkhead out in the cockpit locker then just run the lines? The pump is not loud but not silent either and becomes annoying when sitting watching a movie or relaxing. Mine is out in the very back, as far away as possible actually mounted to the transom, and was still annoying. One more thing if you don't know what flooring you going to use you could have routed the edges of the holes and mounted the heaters and fans from the inside, so all you see is the cut out when looking from the saloon and no matter the flooring it will fit.

  • Nice video, get well soon

  • Water heater, not “hot water heater”! Why would you heat hot water? I rather heat cold water, especially when taking a shower.😉😎💪🥵 You’re doing a great job Mads, really enjoy your videos. Hope you feel better. Exhaust one meter forward from the stern.

  • The most important thing is the ventilation! Not only inside the sailboat, but also the air in and out of the sailboat. Without good ventilation, you'll get condensation! A LOT! Kind regards.

  • For the heater fan units, do you have plans for a return inlet to let air back behind so it can be heated and recirculated? Hope you are feeling better. Wrap a hot towel around your head, and get some soup, champ.

  • Definitely on the stern,safer from heeling,feel better.

  • Mads, what is the BTU output, enjoy your channel very much.

  • you need to vent the under seat storage area so that the fans can pull "new air" from the whole cabin.

  • It seems that the 5 gallon holding tank should be able to keep the heated fluid HOT. Thus it seems like it should be WELL INSULATED in order to do so. Te expansion tank, maybe not so much, but...............

  • Glad to see you are feeling better. Stay well Mads. Missing my Sunday Sail Life fix is 💩. 😜

  • My heater exhaust is on transom next to swim ladder. Even off center plenty high to stay dry. It has a cover that can be placed when seas get up if needed.

  • Going to insulate your tanks? I gotta believe they will get super warm, which isn't great for being in that compartment in the summer.

  • Unlikely the heater will be blasting super hot when you're using the ladder. I recommend the transom mounting, and some distance inboard from the rail, since the rail can dip in the seaway in certain conditions.

  • if i do say so myself, its good to have you back. :)