flue puzzle

[Tom766]

Anyone good with puzzles?

This should be easy but i'm having trouble assembling this flue on the boat, I suspect somethings the wrong size or missing?

Have a Rinnai water heater on the wall and found the flue, pictured, in the cupboard. The flue appears to be brand new, the boiler isnt.

Im guessing the large flanged collar is silicone sealed to the roof and the small ring separates the inner and outer flue tubes creating the double skin.

Problem is that the outer tube is exactly the same diameter as the large collar so it will not slide down over it, just sits on top.

Midland chandlers cant help!

    Tom

[rusty69]

You've got all the right bits, but not necessarily for the right heater. 

[Boaty Jo]

I wouldn't muck about if I were you, too risky.

Contact Rinnai and get proper advice from a stockist / approved installer

[Richard10002]

I think that, as long as you don't liveaboard you don't need a flue. My Rinnai is fitted in the kitchen with no flue, and it passed the BSS in 2014.

[MtB]

11 hours ago, rusty69 said:

You've got all the right bits, but not necessarily for the right heater. 

I'd say quite the opposite. I think some bits are missing or wrong. I've only ever installed two or three from scratch and each time I found it very difficult to assemble the pile of flue components into what I considered a satisfactory flue. 

In each case there where no instructions with the flue and neither rinnai nor Morco could give any coherent guidance on the phone. The se flue kits are not made by the boiler  manufacuters. Those I was supplied with where anonymous.  

[MtB]

3 minutes ago, Richard10002 said:

I think that, as long as you don't liveaboard you don't need a flue. My Rinnai is fitted in the kitchen with no flue, and it passed the BSS in 2014.

 

Even if it passed I would say it is foolhardy to use it. 

[bizzard]

I dunno, but the Rinnai would probably only be in use for a about 10 minutes max while taking a shower or doing the washing up, whereas a gas cooker and oven could be going for a couple of hours or so cooking a roast dinner or baking cakes also exhausting into the cabin space. The Rinnai is likely to be a lot higher up than the cooker so its exhaust is likely to escape up the nearest roof vent quicker than the exhaust from the cooker.

[Richard10002]

29 minutes ago, bizzard said:

I dunno, but the Rinnai would probably only be in use for a about 10 minutes max while taking a shower or doing the washing up, whereas a gas cooker and oven could be going for a couple of hours or so cooking a roast dinner or baking cakes also exhausting into the cabin space. The Rinnai is likely to be a lot higher up than the cooker so its exhaust is likely to escape up the nearest roof vent quicker than the exhaust from the cooker.

These were my thoughts and, almost word for word, those of the BSS inspector at the time. In addition, the manual says it has cutout features which monitor oxygen percentages - as a lay man, I obviously don't know how effective the cutouts might be?

In addition, I am sure there was an extensive discussion regarding a Rinnai, (probably mine), discharging its' gases into the cabin. I'm not sure whether MtB contributed, but I can't believe he wouldn't have :).

At present, I only use it for a shower, and I cant recall the last time I had a shower on board, (I have a bath at home!). Having said that, I'm considering doing away with the Truma water heater and hot air blower, so the Rinnai could become my sole source of hot water.

[bizzard]

12 minutes ago, Richard10002 said:

These were my thoughts and, almost word for word, those of the BSS inspector at the time. In addition, the manual says it has cutout features which monitor oxygen percentages - as a lay man, I obviously don't know how effective the cutouts might be?

In addition, I am sure there was an extensive discussion regarding a Rinnai, (probably mine), discharging its' gases into the cabin. I'm not sure whether MtB contributed, but I can't believe he wouldn't have :).

At present, I only use it for a shower, and I cant recall the last time I had a shower on board, (I have a bath at home!). Having said that, I'm considering doing away with the Truma water heater and hot air blower, so the Rinnai could become my sole source of hot water.

As long as the bulkhead its fixed to and ceiling above the Rinnai heater are well shielded it would be ok.

Edited August 11, 2017 by bizzard

[MtB]

The British standard (can't remember the number) mandates flueless appliances may not be installed in rooms of less than 10 cubic metres IIRC. 

[MtB]

Anyway back on topic, I just had a look at my morco flue and that roof collar is pop riveted to the roof. A tube from the top of the Morco is a nice snug fit up inside the roof collar, and the external tube carrying the terminal is a nice snug fit over the outside of the roof collar. 

So the collar in the photo appears too large for this to happen. Send it back!

Edited August 11, 2017 by Mike the Boilerman

[Richard10002]

4 hours ago, Mike the Boilerman said:

The British standard (can't remember the number) mandates flueless appliances may not be installed in rooms of less than 10 cubic metres IIRC. 

I think I exceed the BS by a reasonable amount. My boat is a 45ft cruiser stern. My lounge kitchen where the Rinnai is fitted is about 15 cubic metres 4.6m x 1.9m x 1.7m. In addition, there is a passageway to the bedroom, and there are big gaps at the bottom and top of the bathroom door, so the whole of the inside of the boat is pretty much connected in an almost open plan kind of way.

Does the BS include gas cookers and ovens, which are flueless by default? If so, all spaces with a gas hob must/should exceed 10 cubic metres?

So, unless there is another reason not to use it, does my Rinnai sound compliant with regulations, and safe to use?

Genuine question, as you raise some doubts, and I'm reasonably sure these were covered a few years ago - and I'm considering making it my sole source of hot water.

[Tom766]

Stirred something up here!  You'd never get away with no flue on a house boiler so i'd expect the same would apply on a boat you may or may not live in ?

I think if I got a slightly bigger diameter collar for the roof the whole lot would fit. the inner tube slides down and fits nicely onto the draft diverter on the heater. The outer tube just sits on top of the collar, it seems to me that it should slide over this to sit on that large flange which is sealed to the roof. Wondering if a local engineering firm could spin and stretch the ali' collar to give it a couple more millimetres in diameter...

[Richard10002]

I agree that gas central heating boilers in houses are almost certainly all room sealed, as are some boat instant water heaters, as is my Truma Gas hot air and water heater.

Our gas cookers and ovens at home aren't room sealed, and don't have flues, and our water heaters on boats dont run for long, unlike central heating boilers in houses when it's a bit chilly, or cold.

I'm asking some questions because I have a Rinnai which exhausts into the lounge kitchen and, as I have said, I'm sure I asked lots of questions a few years ago, and the conclusion was that it was fine, and wasnt likely to kill me. I also had a BSS inspection in 2014, and the inspector commented on the Rinnai, said it was fine, and gave me an advisory on ventilation, which is based upon everything running at full power at the same time.

If that was all wrong, I'd like to know... Mike quoted a 10 cubic meter space, and my space is 15 cubic meters, or more, so I'm still thinking all is well with my Rinnai.