Webasto Hydronic Heater Best Practices

[Macblaze]

I know this topic has been discussed a billion times but I can't quite seem to get a specific answer to the intended purpose and usage of a hydronic heater in a liveaboard context.

We are a dock (for now) in Victoria — the PNW Victoria — and will be here most of the winter. It's a 38' sailboat with a huge aft cabin and no insulation. To date, temps have been generally above freezing and we have only lost 3 pillows to mildew before we learned not to store them against the hull.

We have a Webasto 90s hydronic heater and three radiators: V-berth/salon, salon, and aft cabin but, under advice of the fellow who sold me the boat, we don't use it and instead use a Camfaro electric heater and a smaller (cheaper) electric heater in the aft cabin. The result is hot spots and cold spots and the occasional breaker thrown when I wimp out and run things full blast. (See this thread)

To date, the only time we have used the Webasto is during the summer up in the Broughtons on cold rainy mornings for an hour or so to warm up the cabin and this morning when I thought I would try it out. Turns out it heats the boat way more evenly and quietly.

So, the question(s).

Despite reading a ton of stuff I have yet to learn anything specific about the Webasto's intended use, duty cycles or day-to-day maintenance.

Is it intended to be used 24 hrs a day when its cold enough to warrant it?
Or for 7 days a week for three months?
Does it need more than a yearly checkup?

I realize (or at least have been told) that using the electric heaters saves wear and tear on the more expensive Webasto, but I have little understanding of what that means. If they were originally truck heaters shouldn't they be able to stand hour after hour and day after day of usage? Or am I better off leaving it as an emergency backup?

Enquiring minds want to know!

[groundtackle]

I'm in Victoria as well. Not living aboard but spend lots of time on the boat. I have a hurricane hydronic furnace and really like it but to just warm up a the boat a bit I prefer to run one or two small electrics. The electrics are 1500 watts so cost around 16cents per hour to run flat out
The diesel heater is more like 0.9l / so over 1$ per hr albeit for more btu's. Then there's the other (maintenance) costs of the furnace. It's great when you're not plugged in though.




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[japarker11]

The Webastos hydronics will certainly provide a lot of warm evenly distributed heat. It will be roughly three times the electric resistance heaters limited by your 30 Amp shorepower. Costs per unit of time used will be higher, as noted above.

But each of these heat sources do not help the condensation issue. It does not take much water carried on board be wet shoes or weather gear">foul weather gear to have droplets forming on any cold surfaces. We have spent several November days aboard in Ketchikan, tied to shore power supplied resistance heaters, saving that expensive diesel. Even with an insulated hull it became so miserable we turned to the Webastos air heater. Drawing cold outside air would not only heat the boat but would also dry things out in a matter of hours. I would strongly recommend using outside air for one of the fan coil units on the hydronics system. As for duty cycle on the Webastos, they will run until the Racors plug. A flexible dryer vent tubing routed from a dorade to the inlet of the FCU would do the trick.

Winter moorage in front of the Empress is on our bucket list for some future year. Hope you are enjoying yours.
John

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[Lepke]

I live on a power boat with boiler - a large version of a Webasto. The boat came with water base boards and took hours to warm from a cold start. I went to marine forced air heaters similar to car heaters in place of the base boards radiators. Now from cold to comfort is about 30 minutes. I also can run at a lower water temperature.
japarker11 is right about the moisture issue. Having a vented heat source draws out the moisture. Most commercial fishermen run diesel stoves and their cabins are dry.

I also plumbed my boiler so waste engine heat can be used to heat the boiler when running. Plumbed like a car heater.

[ve7mdl]

I guess this is a PNW issue since all of us are from this area

We are using a diesel stove and a small diesel heater for the salon, but electric as long as it is not below freezing. One thing we found very useful was a de-humidifier. For a small space there are some that run on 12 volts. For a large space, get a 115 V unit. It works well for us.

Cheers, ....Erik.
m/v B.C. Girl
Richmond, BC

[newhaul]

Diesel heat for comfort and a dehumidifier for dry

[Macblaze]

Thanks for all the good info so far. But the key factoid I am missing is: is it ok to run the Webasto for 24/7 for a couple of days when its cold (-1°C as I type)?

Thanks

[transmitterdan]

Originally Posted by Macblaze

Thanks for all the good info so far. But the key factoid I am missing is: is it ok to run the Webasto for 24/7 for a couple of days when its cold (-1°C as I type)?

Thanks

Yes, it is ok to run it. In fact the longer and hotter it runs the better. Often diesel heaters are oversized or run in cool temps and so they don't run long enough and hot enough to burn off the carbon deposits.

I don't like running any type of heater when no one is on board. An exception is certified "bilge heaters" with safety cutoffs and relatively low operating temps.

[newhaul]

Originally Posted by Macblaze

Thanks for all the good info so far. But the key factoid I am missing is: is it ok to run the Webasto for 24/7 for a couple of days when its cold (-1°C as I type)?

Thanks

Yes it is just fine to turn it on and heat the boat until spring with it just don't run out of fuel ( personal experience )

[newhaul]

Originally Posted by transmitterdan

Yes, it is ok to run it. In fact the longer and hotter it runs the better. Often diesel heaters are oversized or run in cool temps and so they don't run long enough and hot enough to burn off the carbon deposits.

I don't like running any type of heater when no one is on board. An exception is certified "bilge heaters" with safety cutoffs and relatively low operating temps.

I agree with no portable electric heaters but do you turn off your furnace in your dirt home when you go to the store?
The wabasto has safety built into it so its safe

[Pyxis156]

We like to cruise in the winters and are in the PNW as well. We have run our Espar hydronic heater pretty much 24/7 for three days straight before. At night we turn the thermostats down some so it would turn off occasionally at night, but for this one time I am referring to it was cold enough to make the system run pretty much continuously. No problems and we have not ever serviced the unit. I finally tracked down a service manual for our unit just last month thinking I might take it apart after this winter to see if there is any buildup or cleaning that needs to be done. I think the fact that you find so little information out there on regular servicing or cleaning for these types of boilers indicates they are pretty robust.

On especially cold days we have occasionally experienced the unit having to go through a second start sequence (which it does automatically without intervention) before it fires up. I have seen a few cases of problems posted that were caused by a bad glow plug or clogged fuel filters leading to low fuel flow but surprisingly few issues with the boiler itself. Again, all the above pertains to our Espar and while I believe it and the Webasto are very similar beasts, YMMV...

[rfadler]

Originally Posted by Macblaze

Thanks for all the good info so far. But the key factoid I am missing is: is it ok to run the Webasto for 24/7 for a couple of days when its cold (-1°C as I type)?

Thanks

Absolutely. Assuming it's installed correctly you could run it all winter long. We have a Webasto 2010 and ran it for 5 days straight while anchored in False Creek in Vancouver. I have received very good support from Sure Marine in Seattle where I purchased our system. They are very supportive of do-it-youselfers.

[pdxsailordiver]

I have a Webasto AT3900. I added a digital thermostat and leave it set at 40 when I'm not on the boat . Small electric oil filed heater keeps the boat warm but if there is a power outage the Webasto will keep things warm. After talking to Webasto support I only run it on kerosene.
When we are anchored out my wife has complete control of the thermostat. Now she will go out any time of the year.

Tim Hryciw
S/V Maria Victoria

[Stu Jackson]

Originally Posted by Macblaze

but, under advice of the fellow who sold me the boat, we don't use it

Do you still know this guy? I'd ask him why he told you that, since we can't go back in time and suggest you should have done so back then.

It is always difficult on a forum to even begin to answer a question put like this, since we weren't there and have no idea why anyone would install something on a boat that couldn't be used. My guess is you were so wrapped up in the purchase of the boat that this one detail slipped. Too bad.

ITWMB, I'd do what you said you done in your OP: find all the service info you can can, and use it.

Good luck. And it's there so you can stay warm.

[Macblaze]

Originally Posted by Stu Jackson

Do you still know this guy? I'd ask him why he told you that, since we can't go back in time and suggest you should have done so back then.

Good luck. And it's there so you can stay warm.

I did ask. He said something along the lines of why would you use an expensive, delicate piece of equipment when you could just use electric heaters. And yes, since it was warm and spring and I wanted to go sailing, I left it at that :-)

His statement is mostly why I am enquiring. What I took as fact and general best practice then now seems a bit specious...I just couldnt find anything to contradict him.

Thanks!