Gas water heater installation

[Geoff Walton]

Hi, we are in the process of refurbishing our narrowboat and in particular we want to install an instantaneous gas water heater. Currently room sealed ones are very expensive so we are looking at the conventional type. Although these are permitted by BSS there is still the concern that there could be a build up of carbon monoxide gas. Our plan is to install the heater in a cupboard in the kitchen. It would be quite simple to make this cupboard air tight internally but add a large air vent in the cupboard to the outside. The flue would go out through the roof as the old heater did. This arrangement would affectively put the gas heater outside the boat where it could get all the air it needs and disperse any unwanted gases. Seems too simple.

Thoughts anyone?

[Tony Brooks]

And unless it has electronic ignition, winds on the side of the boat might blow out the pilot flame.

 

There must still be many tens of hundreds of boats with such heaters, and you do not hear much, if anything, about the causing deaths from CO, especially now it is mandatory to fit CO alarms to boats.

[Ex Brummie]

There is a cut off date of the boat build which precludes the fitting of open flue gas appliances in narrowboats. I can't be a***d to check the BSS regs myself, but would suggest you do.

[alan_fincher]

3 hours ago, Ex Brummie said:

There is a cut off date of the boat build which precludes the fitting of open flue gas appliances in narrowboats. I can't be a***d to check the BSS regs myself, but would suggest you do.

 

There is no cut-off date in the BSS regs.  You can fit one to any age of boat.

The same may not be true if the RCD applies though - that's not anything I know about as both my boats are 87 years old!

[MtB]

12 hours ago, alan_fincher said:

The same may not be true if the RCD applies though - that's not anything I know about as both my boats are 87 years old!

 

From some point in 1998 open flue appliances (such as a Morco) were banned from any boat requiring RCD compliance.

 

If the OP's boat is later than 1998 then s/he may not fit an open flue water heater and remain RCD compliant. Whether this will have them waking up night after night with worry or if they couldn't give a toss is up to them to decide. Many boaters couldn't give a toss as there is no official enforcement whatsoever. But there is an argument that if your boat is legally required to RCD compliant and if isn't, your insurance company might sieze on this as an excuse not to pay out in the event of a claim. Again this may have the OP tossing and turning at night with worry, or they may take a more pragmatic view and shoulder that (microscopic) risk themselves. Also, there are persistent rumours that certain sniffy brokers won't sell a boat without RCD (or by extension, an RCD breached by installation of an open flued appliance). Again the OP is free to decide if they care not a jot about this, or if they do care a jot. 

 

Like you I don't think there is anything in the BSS about open flue appliances not being allowed.

 

Alan De E tends to quote reems of irrelevant waffle from BSS in threads like this, which still nets down to what you and I just said. 

 

 

Edited October 5, 2023 by MtB
Add a bit.

[David Mack]

11 hours ago, MtB said:

Alan De E tends to quote reems of irrelevant waffle from BSS in threads like this,

And frequently states things as 'legal requirements' when they are actually from documents giving 'guidance' or setting out 'best practice'.

[BEngo]

18 hours ago, Geoff Walton said:

Our plan is to install the heater in a cupboard in the kitchen. It would be quite simple to make this cupboard air tight internally but add a large air vent in the cupboard to the outside. The flue would go out through the roof as the old heater did. This arrangement would affectively put the gas heater outside the boat where it could get all the air it needs and disperse any unwanted gases. Seems too simple.

Thoughts anyone?

On the face of it it is simple.  However, once you have boxed the heater in (out?)  you are no longer able to get at the controls, have gas  joints  inside the box which in BSS speak are not readily accessible so are a failure point and you  will have a right rigmarole of dismantling and reassembly if/when you need to service the heater. The gas inlet pipe will need to be sealed as it enters the box and  there also may be electric cables which  need to be sealed where they pass through the box walls.

 

 Extending  the controls through the box to make the thing useable  will mean more holes in the box so it is no longer room sealed and are a modification which I doubt is RCD compliant unless the OEM approves it.

 

So, no, it ain't as simple as it looks!

N

[MtB]

1 minute ago, BEngo said:

On the face of it it is simple.  However, once you have boxed the heater in (out?)  you are no longer able to get at the controls, have gas  joints  inside the box which in BSS speak are not readily accessible so are a failure point and you  will have a right rigmarole of dismantling and reassembly if/when you need to service the heater. The gas inlet pipe will need to be sealed as it enters the box and  there also may be electric cables which  need to be sealed where they pass through the box walls.

 

 Extending  the controls through the box to make the thing useable  will mean more holes in the box so it is no longer room sealed and are a modification which I doubt is RCD compliant unless the OEM approves it.

 

So, no, it ain't as simple as it looks!

N

 

 

In addition to all this, I bet the manual states not to be installed in a "compartment" (technical term for what the OP is proposing).

 

If compartment installation is permitted, the manual will give chapter and verse about materials the compartment can be made from, fire proofing, labelling and ventilation requirements.

 

 

[Tacet]

13 hours ago, MtB said:

 

From some point in 1998 open flue appliances (such as a Morco) were banned from any boat requiring RCD compliance.

 

If the OP's boat is later than 1998 then s/he may not fit an open flue water heater and remain RCD compliant. Whether this will have them waking up night after night with worry or if they couldn't give a toss is up to them to decide. Many boaters couldn't give a toss as there is no official enforcement whatsoever. But there is an argument that if your boat is legally required to RCD compliant and if isn't, your insurance company might sieze on this as an excuse not to pay out in the event of a claim. Again this may have the OP tossing and turning at night with worry, or they may take a more pragmatic view and shoulder that (microscopic) risk themselves. Also, there are persistent rumours that certain sniffy brokers won't sell a boat without RCD (or by extension, an RCD breached by installation of an open flued appliance). Again the OP is free to decide if they care not a jot about this, or if they do care a jot. 

 

Like you I don't think there is anything in the BSS about open flue appliances not being allowed.

 

Alan De E tends to quote reems of irrelevant waffle from BSS in threads like this, which still nets down to what you and I just said. 

 

 

 

Alan knows much more about this type of thing, but where/what is it that bans open flue appliances?

 

The Recreational Craft Regulations 2017 require gas appliances to be installed in accordance with manufacturers' instructions and maybe that precludes it in practice, but where is the rule in principle?

[MtB]

2 minutes ago, Tacet said:

Alan knows much more about this type of thing, but where/what is it that bans open flue appliances?

 

The Recreational Craft Regulations 2017 require gas appliances to be installed in accordance with manufacturers' instructions and maybe that precludes it in practice, but where is the rule in principle?

 

I spent a whole day back in about 2002 studying the RCD and it is definitely in there. Curiously I don't remember which page it is on.

 

You are asking about the RCR which is a different regulation. Interesting you seem to be suggesting the ban on open flue has been dropped now. 

[Tacet]

5 minutes ago, MtB said:

 

I spent a whole day back in about 2002 studying the RCD and it is definitely in there. Curiously I don't remember which page it is on.

 

You are asking about the RCR which is a different regulation. Interesting you seem to be suggesting the ban on open flue has been dropped now. 

I'm questioning - not suggesting!  Elswehere 'Alan de Enfield' has said that the RCD is now called the RCR, which makes sense to me.  I.e a former EU Directive has morphed into a good old UK Regulation. And until you get to the bit about engine emissions, the RCR compliance  seems very straightforward in itself.

 

From another thread, about tank inspection hatches, it was (I think) eventually concluded these are not required despite earlier assertions to the contrary.  There was nothing drawn to anyone's attention otherwise.

 

The RCD (and I genuinely don't understand what that has now to do with UK boats) was quoted as broadly saying that compliance with ISOs was deemed to be compliance with its own requirements.  And the ISO (or was it British Standard?) required inspection hatches.  But the concensus of the small number that remained interested seemed to be that neither the RCR or RCD required full compliance with ISOs.

 

 

Just now, Tacet said:

I'm questioning - not suggesting!  Elswehere 'Alan de Enfield' has said that the RCD is now called the RCR, which makes sense to me.  I.e a former EU Directive has morphed into a good old UK Regulation. And until you get to the bit about engine emissions, the RCR compliance  seems very straightforward in itself.

 

From another thread, about tank inspection hatches, it was (I think) eventually concluded these are not required despite earlier assertions to the contrary.  There was nothing drawn to anyone's attention otherwise.

 

The RCD (and I genuinely don't understand what that has now to do with UK boats) was quoted as broadly saying that compliance with ISOs was deemed to be compliance with its own requirements.  And the ISO (or was it British Standard?) required inspection hatches.  But the concensus of the small number that remained interested seemed to be that neither the RCR or RCD required full compliance with ISOs.  Again that makes sense.  The BSS requirements are the least onerous, the next is RCR and to ISO/BS are the toughest.  But you don't always need to meet the gold standard.

 

 

 

[David Mack]

41 minutes ago, Tacet said:

The RCD (and I genuinely don't understand what that has now to do with UK boats)

The RCD was updated in 2017, when we were still in the EU. Following Brexit the 2017 RCD has been copied across effectively unchanged as the RCR. So strictly, relevant UK craft have to comply with the RCR, not the RCD. But in practice it makes no difference at present (until one or both documents gets amended, withdrawn or replaced).

Edited October 5, 2023 by David Mack

[Ex Brummie]

Like I said, I couldn't be a***d to look up the regs, and  have great respect for those who know chapter and verse and share it. 

I knew there was some quasi regulatory restriction .

[Stroudwater1]

I’m confused as the heater is to vent out of the roof like the old heater. So does that imply that the OPs boat already had one? 
 

Our Paloma heater is in a large cupboard and has been since 1993. There’s a decorative open vent in the front of the cupboard into the corridor between bedroom and kitchen. All seems fine, the CO meter is next to the cupboard but seems happy. 
 

It maybe best to call a plumber who does BSS checks as well and ask about it and then they could fit it if they were happy with the concept? 
 

 

[blackrose]

I don't understand why so many posts here are going on about the technicalities of RCD or RCR compliance when the OP only mentioned BSS requirements? Has this boat been built to RCD safety standards? If not then isn't the RCD irrelevant to the OP?

 

I fitted a non-room sealed Valiant instant gas water heater to my 2005 sailaway and then replaced it with a Morco D-61 a few years ago. Both have passed BSS inspections so there's no need to install it in a cupboard. If CO was an issue then you'd need to install your gas hob and oven in a cupboard too! 

 

In fact you're probably more likely to create CO by fitting a non-room sealed gas water heater in a cupboard as in the OP's scenario because you're then relying on a single vent (of unknown adequate size?) to the outside. Also if the vent gets blocked with spiders web and dirt or the wind is blowing the wrong way you might have a lack of air to the heater and incomplete gas combustion leading to the formation of CO inside the cupboard, and unless that cupboard is gas tight it will escape into the boat. Just a bad idea in my opinion.

Edited October 6, 2023 by blackrose

[Geoff Walton]

Hi Guys, lots of feed back thank you.

Some feed back from me.

As far as I can see non-room sealed instantaneous water heaters are allowed by BSS for the time being until something better comes along. This is because they have a good safety record. To date I have not found a heater manufacturer that would approve their room sealed heater for narrowboat use. Glad to proven wrong about this. Our boat was built circa 1997 and was fitted with a central heating gas boiler.

The cupboard I am proposing would have door with a rubber seal so access would be no problem. I accept that a there will be the need to seal all the joints and holes. I was contemplating a 200 x 200 vent in the side of the boat. Should be adequate to keep the most enthusiastic spiders at bay.

The issue with burning LPG is the gradual build up of carbon monoxide in your body. Generally you use hobs and ovens for a short time and hence not too much of a problem, Whereas water heaters can run for some time and use a lot more gas. Evidently carbon monoxide stays in your body for up to 4 hours so if you are not careful you can keep topping it up until it reaches a dangerous level. I don't know anything about RCD or RCR perhaps someone can point me in the right direction to read about it. It has been good to have your comments, my next move is to find a boat registered gas engineer to get their advice on the installation.

[MtB]

8 hours ago, Geoff Walton said:

my next move is to find a boat registered gas engineer to get their advice on the installation.

 

Any RGI will have a purple fit at your proposals to DIY-convert an open flue appliance to room sealed, and will refuse to be involved in any way. 

 

 

[Tony Brooks]

8 hours ago, Geoff Walton said:

Generally you use hobs and ovens for a short time and hence not too much of a problem, Whereas water heaters can run for some time and use a lot more gas.

 

Are you sure about that? Even a 5-minute shower will only burn gas for about five minutes - how long does it take to bake a cake or a Sunday roast in the oven, or cook vegetables on the hob? I think that you seem very confused. I don't know for sure, but I suspect cooking a decent roast meal will take longer and use more gas than the typical run time of an instant gas water heater.

[MtB]

Half-arsed proposals based on flawed understanding are one of the reasons we have the gas regulations and BSS in the first place. 

 

I'd be surprised if an open flued water heater such as a Morco can be compartment-installed and remain in compliance with the manufacturer's installation instructions. But I haven't read the manual for a few years now so there may be a section on how to do it safely. 

Point being, I think the OP's proposal will be a BSS fail anyway.

[Tacet]

On 05/10/2023 at 11:45, David Mack said:

The RCD was updated in 2017, when we were still in the EU. Following Brexit the 2017 RCD has been copied across effectively unchanged as the RCR. So strictly, relevant UK craft have to comply with the RCR, not the RCD. But in practice it makes no difference at present (until one or both documents gets amended, withdrawn or replaced).

Thanks.  Whenever I try to look at the RCR or RCD

 

https://web.archive.org/web/20120608095401/http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:1994:164:0015:0038:EN:PDF

 

it only seems to have reasonably basic requirements, mostly along the lines of everything should be adequate for the job; there are some areas of exception.

 

Yet MtB recalls some RCD stuff  about open flue appliances; where is this to be found, for example?  Or was it/is it a lot simpler than some would have us believe?

[David Mack]

1 hour ago, Tacet said:

Thanks.  Whenever I try to look at the RCR or RCD

 

https://web.archive.org/web/20120608095401/http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:1994:164:0015:0038:EN:PDF

That's the 1994 EU original. The current UK version is at https://www.legislation.gov.uk/uksi/2017/737/contents

 

1 hour ago, Tacet said:

it only seems to have reasonably basic requirements, mostly along the lines of everything should be adequate for the job; there are some areas of exception.

British Marine has produced a guidance document which sets out a lot of detail of one way to comply with the high level requirements, which lists a lot of international standards and says you should comply with all of them. A certain forum member is keen on quoting huge chunks of it as gospel, when it is not. That said, compliance with all those standards probably will satisfy any authority that you comply with the RCR, but doing so will require you to buy, read and understand hundreds or thousands of documents.

[system 4-50]

10 hours ago, Geoff Walton said:

The issue with burning LPG is the gradual build up of carbon monoxide in your body. Generally you use hobs and ovens for a short time and hence not too much of a problem, Whereas water heaters can run for some time and use a lot more gas. Evidently carbon monoxide stays in your body for up to 4 hours so if you are not careful you can keep topping it up until it reaches a dangerous level

This sort of information is how you can build urban? myths.  In practical terms it is a load of twaddle imho.

[blackrose]

8 minutes ago, system 4-50 said:

This sort of information is how you can build urban? myths.  In practical terms it is a load of twaddle imho.

 

And not just in your humble opinion. It's just a load of twaddle.

 

If any non-room sealed appliance is going to emit CO then how about your multi fuel stove? That can burn for 24 hours a day in winter. Perhaps they should all be room sealed too! 🙂

2 hours ago, Tony Brooks said:

 

Are you sure about that? Even a 5-minute shower will only burn gas for about five minutes - how long does it take to bake a cake or a Sunday roast in the oven, or cook vegetables on the hob? I think that you seem very confused. I don't know for sure, but I suspect cooking a decent roast meal will take longer and use more gas than the typical run time of an instant gas water heater.

 

Yes indeed. The longest my gas water heater generally stays on continuously is about 5 or 10 minutes maximum while I have a shower or do some washing up, whereas my oven can be on for 2 hours to cook a joint of meat. Likewise my hob can stay on for half an hour or more.  I'm not sure what sort of world Geoff is living in if it's the opposite on his boat? 

Edited October 7, 2023 by blackrose

[Tony Brooks]

23 minutes ago, blackrose said:

 

And not just in your humble opinion. It's just a load of twaddle.

 

If any non-room sealed appliance is going to emit CO then how about your multi fuel stove? That can burn for 24 hours a day in winter. Perhaps they should all be room sealed too! 🙂

 

Yes indeed. The longest my gas water heater generally stays on continuously is about 5 or 10 minutes maximum while I have a shower or do some washing up, whereas my oven can be on for 2 hours to cook a joint of meat. Likewise my hob can stay on for half an hour or more.  I'm not sure what sort of world Geoff is living in if it's the opposite on his boat? 

 

Also on a cooker boiling over and fat spills in the oven are probably more likely to clog burners, so the combustion is inefficient far more easily than the partially enclosed water heater burner.

[Tracy D'arth]

I have never read of a maker whose instructions will allow an open flued gas burning appliance to be built into a cupboard with a vent to the outside to try to modify it to a balanced flue.  Regardless of any boat building regs, it must be installed in accord with the manufacturer's instructions.

If you want to hide it, hang a backless cupboard over it so that it can be lifted off for servicing but there will be minimum distances to be checked and heat/fire proofing of the "cupboard"