Merryfisher 805 heating and hot showers

[freddyuk]

Here are some images of my heater system installation and my hot/cold deck shower where you can actually stand up (unless you are 6'+)
The diesel heater is bolted to the transom behind the rudder stock using the existing swim platform bolts and some stainless solar roof brackets I had lying around. The diesel supply will be T'd into the main tank using some copper tubing (I used the plastic pipe for testing). The exhaust is bandaged and secured to the same row of bolts with stand off brackets going up to the outlet on rear corner. The tiller is secured above here to get it out of the way. There is a smoke alarm inside the lazerette and an auto fire extinguisher.
The heater outlet splits with one pipe going up inside the rear transom space then through the storage bin and into the shielded outlet butterfly vent. With the covers on this keeps the rear deck toasty but can be turned off and the rain hood keeps it dry. The main outlet is fed via insulated 4" hose round behind the fuel tank and along under the saloon floor where it splits with one outlet up inside the front seat storage bin and out under the saloon table. The other outlet continues into the front cabin. In order to get the large diameter heater duct out from the lazerette you have to cut a round hole in the bulkhead behind the fuel tank. The only way to do this is to remove the house battery and feed yourself feet first forward into the hole under the saloon table and get your head down towards the stern with drill and cutter in hand. If you are claustrophobic DO NOT TRY THIS. You will not be able to quickly exit from this position. The heater pump can be heard inside the boat as a very faint tapping and this comes via the holes in the rear bulkhead so sealing these would eliminate any noise.
The inverter is housed on a fireproof board in the battery void. Input DC power is fed up into the saloon to a recessed isolator switch (via inline fuse). The AC power is fed via a 4 pole transfer switch from the AC breaker box - or the inverter - to the sockets.
The solar input keeps the battery topped up and feeds the low voltage supplies to the diesel heater, Netgear Aircard hotspot, USB charging socket and the backup engine temperature gauge.
The rear deck shower is plumbed into the hot and cold supplies in the lazerette and fed up inside the starboard void. There is a mixer tap unit below and a rubber covered access point above for the shower hose. I need to fit the gasket to the hose to keep the water out of the hole. The stainless shower hose is not good enough for saltwater so needs replacing but it does need to be flexible to work well.
With the covers on you can shower in comfort.
The boat is a mess as I have been laid up with a slipped disc since August so sorry about that. A few things to finish still as is the way.

 

[Seastoke]

When you say bandage , is it for the correct temp aS WHEN I BOURGHT MY PREVIOUS BOAT , the seller had fitted heater but coukd not get it going , just needs resetting but the bandage gave off fumes and it could have been a different story.

 

[freddyuk]

When you say bandage , is it for the correct temp aS WHEN I BOURGHT MY PREVIOUS BOAT , the seller had fitted heater but coukd not get it going , just needs resetting but the bandage gave off fumes and it could have been a different story.

It is proper exhaust bandage for the purpose. It does n ot give off any fumes but it is horrible stuff to get on your skin as the fibreglass is very irritating. Lying on your back with head stuffed up under the transom is yet another job best done once properly.

 

[freddyuk]

Here are some images of the heater mounting. I used Bighead fastners inside the heater case to provide fixing studs.

 

[spannerman]

Your exhaust should have a swan neck meaning it loops up above the outlet then down to the outlet thus ensuring no water or spray can run down into the heater. Can’t see in the pic but just thought I’d mention it.

 

[freddyuk]

Indeed it does do exactly that. It is as high as I could reach with the pipe going up in a loop. This is the only image I have with some idiot rafting up against me sawing through my gel coat.
The safety items in the lazerette.

 

[spannerman]

I’d remove those lines of his PDQ, that just typical of the incompetent and selfish people there are in our hobby who shouldn’t be allowed to own anything more complex than a pedallo. If thats his idea of responsible rafting I’d tell to find somewhere else.

 

[freddyuk]

Don't worry I moved it immediately. A serial offender I am afraid.

 

[chamac]

Thanks for posting this Freddy, the article and photos are a great help.
I have this job on the winter job list for my newly accuired 805.
Can you remember roughly what length of hot air duct and exhaust you used?
I don't have a canopy so the cockpit shower and heat would be a future add-on.
I don't have hot water yet so will have to stick with the garden sprayer and kettle until then.
I intend fitting the calorifier in the same void the starting battery, port side.
Is that the normal site where its fitted?
Charlie

 

[Jamie Dundee]

Don't worry I moved it immediately. A serial offender I am afraid.

I'd have removed it with a big knife...?

 

[freddyuk]

Thanks for posting this Freddy, the article and photos are a great help.
I have this job on the winter job list for my newly accuired 805.
Can you remember roughly what length of hot air duct and exhaust you used?
I don't have a canopy so the cockpit shower and heat would be a future add-on.
I don't have hot water yet so will have to stick with the garden sprayer and kettle until then.
I intend fitting the calorifier in the same void the starting battery, port side.
Is that the normal site where its fitted?
Charlie

The hot air duct was in a box of 10m compressed into 1m. There was more then enough as the boat is 8m so I used about 6m. Supplier link here: Aluminium - Insulated - 10m Length
I am in Ireland so getting kit to install the heating and hot water was a nightmare. I found the ducting and fittings were always the wrong size and stupidly expensive so I have quite a collection left over.
The hot water was fitted in the centre of the boat in front of the engine. I did not want to have a big house battery and calorifier on the same side. In the void under the table is a 120ah battery with starter battery in the engine compartment. I moved the engine battery to one side in the bilge. Some wedges were fashioned out of plastic wood and stuck to the hull to make a flat platform for the calorifier which was bolted through the front panel. There is still enough room to get the pumps and impellers serviced and access is via the hatch under the steps. I had 2 extinguishers here which I moved to the rear of the engine.
The pipework was run from the calorifier back to the sink where the connections were T'd in under the floor. The immersion was wired back to the switch panel with 2.5mm rubberised cable.
I attach some more images including the swan neck for the heater exhaust and the solar controller and isolator for switching AC between shore and inverter power. Inverter is 1500w so can run the immersion at 1000w if required for short periods. The engine does a good job of heating via the cooling system.
If you need help with installation I can take more photos.
A couple of quick fixes depending on which boat you have. Roof drain normally dumps onto the back deck so install a pipe to rake this outside the boat.
For somewhere to put a cup of tea a simple shelf slotted into the cabin side storage is useful. Two bits of plywood and some moulding does the job although the moulding was not fitted when this image was taken.
Have fun.

 

[chamac]

Thanks Freddy for the new photos and info.
I am in Ireland too and know full well what you are talking about.
I recently had to drill out the lock on my boat door (lost the key) and ordered a replacement from a company in the UK.
It was the only place I could find one online, anyway it was sent six weeks ago and still hasn't arrived.
Since Brexit, ordering from my usual toy shops has become a disaster.
I suspect there is some sort of conflict going on between the powers that be post brexit.
I will take a chance on the ducting as it is great value.
I see stainless skin fittings and exhaust ducting and nice quality stainless silencers on ebay.
There is a company doing vehicle heaters in Kildare who have a lot of stock.
Two Irish suppliers have been out of calorifiers for months now so I will have to wait for them to come back in stock.
My roof stores rain water until you move to the port side, then it tries to get you from the drain hole above
so I will try something like your solution. I was going to look at the ladder to see if it could be used.
Did you fit the exhaust skin fitting on the transom? Is that it under that dodgy shore line on one of your photos?
I was thinking high up above the engine exhaust exit on the transom.
Thanks again for your help.
Charlie

 

[freddyuk]

I have quite a few bits you may need if you are in Ireland. I have the bits to mount the heater if you doing it similar to mine and various ducting etc. I bought a bag of plastic hose barb fittings for that roof drain as I could not buy 1. I have some insulated hose left over and can measure it unless you need most of the full length as I did. Check with me rather than buy new.
I use ASAP Supplies in UK. SVB in Germany, EU Yacht shop and Ebay. Probably some others too. The heater fittings are a rip off so plan it very carefully first. Trying to buy everything from one shop does not work!! Some UK suppliers stopped sending stuff to Ireland as it was too much hassle.
I bought the proper silencer and exhaust skin fitting as cheap vehicle silencers can leak gases. The skin fitting is right above the engine exhaust so it is not in the way of fenders and high enough to avoid following seas. I did not fit a drain on the exhaust which is recommended as it was getting very expensive. I think skin fitting was £75 alone. I am happy to do more photos to assist.
Have you got the Nanni 4.390??

 

[chamac]

Thanks for your offer. This is a job that will not be done together.
I have stainless angle plate that should be ok for mounting the heater to the bolts on the transom.
Going to order a stainless exhaust skin fitting from Aliexpress.
I find that most stuff from China gets through customs easier that stuff from the UK.
The exhaust pipe would need to be good quality and wonder if the Ali stuff would be good enough.
€70 for the exhaust silencer and possible VAT charges on that. Not clear if it is from the UK or Turkey.
S/S 22MM MARINE AIRTIGHT EXHAUST SILENCER EBERSPACHER WEBASTO DIESEL HEATER CLAM | eBay
I will order a box of the hot air ducting from your supplier and see if it gets here. I will need most of the 10 meters.
I was originally going to duct the hot air into the engine bay and out under the steps somewhere.
That would get hot air into the shower area, berths and cabin in one go.
Might be worth putting a openable diversion T into the windscreen ducts.
I will fit the heater and work from there.
Yep, I have the Nanni 4.390. That was number 1 box to be ticked. It has just 140 hours from new.
As a previous VP owner, I love the cheap Toyota parts and easy servicing.

 

[freddyuk]

I decided against going through the engine bay. It was going to mean taking up valuable storage space in the lazerette; cutting through the silencing foam; adding to the access issues in the engine bay which is already tight and of course it would mean I could not fit my calorifier and battery where I wanted them. There is so much dead space round and behind the fuel tank and inside the void behind the cabin I went that route. The heaters pump out a lot of heat so one outlet in the cabin should be enough for the heads area too. I could not get into the void where the battery charger etc. is located no matter how I tried so this was a difficult area to work in. I left my screen hester ducts hanging where they were as it was too difficult to find correct connectors and be able to reach in to fit it all.! I am waiting to find a small child to send in there to finish the job......

 

[chamac]

Thanks for the photos Freddy
I will be on her this weekend so will have a look at your routing.
Looks like it makes sense.
I might put the calorifier in behind the starter battery, depending on which size I go for,
I like the fact that i can squeeze down (just) in front of the engine to work on it.

 

[lynallbel]

Thanks Freddy for the new photos and info.
I am in Ireland too and know full well what you are talking about.
I recently had to drill out the lock on my boat door (lost the key) and ordered a replacement from a company in the UK.
It was the only place I could find one online, anyway it was sent six weeks ago and still hasn't arrived.
Since Brexit, ordering from my usual toy shops has become a disaster.
I suspect there is some sort of conflict going on between the powers that be post brexit.
I will take a chance on the ducting as it is great value.
I see stainless skin fittings and exhaust ducting and nice quality stainless silencers on ebay.
There is a company doing vehicle heaters in Kildare who have a lot of stock.
Two Irish suppliers have been out of calorifiers for months now so I will have to wait for them to come back in stock.
My roof stores rain water until you move to the port side, then it tries to get you from the drain hole above
so I will try something like your solution. I was going to look at the ladder to see if it could be used.
Did you fit the exhaust skin fitting on the transom? Is that it under that dodgy shore line on one of your photos?
I was thinking high up above the engine exhaust exit on the transom.
Thanks again for your help.
Charlie

I used that same ducting when doing my heater last year, bit of a fiddle to fit, and I found peeling back the foil and the insulation then clipping the inner over the stub, carefully put back insulation and foil using another clip seemd to work well, so bascially it is double clipped

 

[freddyuk]

Thanks for the photos Freddy
I will be on her this weekend so will have a look at your routing.
Looks like it makes sense.
I might put the calorifier in behind the starter battery, depending on which size I go for,
I like the fact that i can squeeze down (just) in front of the engine to work on it.

Go for the vertical version as better access and needs less energy to heat what you need. I also got larger diameter outlet fittings for decent size pipe. 22 litre fits nicely. Trick for me was to get the left foot in behind the alternator and the right foot near the air vent inlet. You can then reach most things. Kneel on the right leg and you can get to the lower pumps etc. but it is a faff. A piece of timber across the bilge helps a lot.

 

[chamac]

Just an update,
Got my exhaust transom fitting from Aliexpress.
It took about a week from China to Ireland !! Its very well made.
I have the stainless elbow and silencer coming from Southern Marine Products
who were great to deal with and no problem shipping to Ireland.
I will try Dust Spares for the ducting.
Just need the exhaust pipe and better fuel line.
Freddy, I will use your routing as it does just use empty space so no loss there.

 

[simonfraser]

Thanks for posting this Freddy, the article and photos are a great help.
I have this job on the winter job list for my newly accuired 805.
Can you remember roughly what length of hot air duct and exhaust you used?
I don't have a canopy so the cockpit shower and heat would be a future add-on.
I don't have hot water yet so will have to stick with the garden sprayer and kettle until then.
I intend fitting the calorifier in the same void the starting battery, port side.
Is that the normal site where its fitted?
Charlie

how many hot kettles does it take to get the garden sprayer up to shower temp ?