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The oven is 45 feet from the hob?

The boiler is on the "other side", but is only 3 feet from the oven. How does that work? Remember we are talking about pipe length here, so you need to take into account the vertical distances as well as horizontal if the pipe is crossing from one side to the other. You will also have to add in for the extra bends/elbows involved.

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Ok, calculating your pipe sizes and allowing for fittings as shown, we have:

 

From the regulator to inside the cabin bulkhead on the port side, 10mm pipe via 2# bulkhead fittings, 2# pulled slow bends into 1# 10mm tee.

From that 10mm tee branch across the forward bulkhead and down the starboard side to the boiler, 10mm pipe via 2#  elbows and 3# pulled slow bends.

From the 10mm tee, reduced to 8mm on the end  to oven and hob via 1#  8mm tee,   2#  8mm elbows  and 2# pulled slow bends.

 

Keep fittings and bends to a minimum. No kinks. Pipework supported every 0.3m, all fittings supported.  The bottle regulator and hose must be minimum 10mm bore not 8mm.

 

Test nipples on end of runs at boiler and oven.

 

This will supply with all appliances lit with  a pressure drop within 0.125 kPa.

 

E&OE

 

 

Edited by Tracy D'arth
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3 hours ago, Tracy D'arth said:

Ok, calculating your pipe sizes and allowing for fittings as shown, we have:

 

From the regulator to inside the cabin bulkhead on the port side, 10mm pipe via 2# bulkhead fittings, 2# pulled slow bends into 1# 10mm tee.

From that 10mm tee branch across the forward bulkhead and down the starboard side to the boiler, 10mm pipe via 2#  elbows and 3# pulled slow bends.

From the 10mm tee, reduced to 8mm on the end  to oven and hob via 1#  8mm tee,   2#  8mm elbows  and 2# pulled slow bends.

 

Keep fittings and bends to a minimum. No kinks. Pipework supported every 0.3m, all fittings supported.  The bottle regulator and hose must be minimum 10mm bore not 8mm.

 

Test nipples on end of runs at boiler and oven.

 

This will supply with all appliances lit with  a pressure drop within 0.125 kPa.

 

E&OE

 

 

Gas taps on both branches would be a good idea too.

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12 hours ago, Tracy D'arth said:

Ok, calculating your pipe sizes and allowing for fittings as shown, we have:

 

From the regulator to inside the cabin bulkhead on the port side, 10mm pipe via 2# bulkhead fittings, 2# pulled slow bends into 1# 10mm tee.

From that 10mm tee branch across the forward bulkhead and down the starboard side to the boiler, 10mm pipe via 2#  elbows and 3# pulled slow bends.

From the 10mm tee, reduced to 8mm on the end  to oven and hob via 1#  8mm tee,   2#  8mm elbows  and 2# pulled slow bends.

 

Keep fittings and bends to a minimum. No kinks. Pipework supported every 0.3m, all fittings supported.  The bottle regulator and hose must be minimum 10mm bore not 8mm.

 

Test nipples on end of runs at boiler and oven.

 

This will supply with all appliances lit with  a pressure drop within 0.125 kPa.

 

E&OE

 

 

 

 

That looks carefully thought out.

 

One point to debate is the need for two test nipples, one on each branch. Some would argue that only one test nipple is necessary for 'whole system' soundness (or tightness, or whatever it's called this week) testing, so two breaches the requirement for 'no unnecessary fittings'. 

 

Arguably the two branch isolators are not 'necessary' either! 

 

On my first NB I fitted a manifold in the gas locker with a separate gas line to every gas appliance, each with an isolator in the gas locker. Always passed a BSS

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30 minutes ago, Alan de Enfield said:

 

Does that pipe meet the minimum wall thickness quoted in the specification ?

 

 

Let's have a guess.....

 

Answer? Probably not, which is why imperial pipe is used.

 

 

 

 

Mind you I'm not sure the OP has ever defined what set of regulamations he wants to comply with. 

 

 

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2 minutes ago, MtB said:

 

 

Let's have a guess.....

 

Answer? Probably not, which is why imperial pipe is used.

 

 

 

 

Mind you I'm not sure the OP has ever defined what set of regulamations he wants to comply with. 

 

 

 

 

Are there multiple standards covering gas installations in 'small boats' then ?

 

Do these multiple standards have differing requirements (that'd be a little unusual - is it pick & mix as to what part of which specification you follow ?)

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1 minute ago, Alan de Enfield said:

 

 

Are there multiple standards covering gas installations in 'small boats' then ?

 

Do these multiple standards have differing requirements (that'd be a little unusual - is it pick & mix as to what part of which specification you follow ?)

 

Yes. I'm surprised you didn't know this.

 

Some like their gas installations to comply with BS PD 54823:2016 Guidance for the design, commissioning and maintenance of LPG systems in small craft. 

 

Still others worry about ISO 10239. 

 

Most don't give a shit and are happy if their boat passes BSS.

 

 

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22 hours ago, Tracy D'arth said:

Ok, calculating your pipe sizes and allowing for fittings as shown, we have:

 

From the regulator to inside the cabin bulkhead on the port side, 10mm pipe via 2# bulkhead fittings, 2# pulled slow bends into 1# 10mm tee.

From that 10mm tee branch across the forward bulkhead and down the starboard side to the boiler, 10mm pipe via 2#  elbows and 3# pulled slow bends.

From the 10mm tee, reduced to 8mm on the end  to oven and hob via 1#  8mm tee,   2#  8mm elbows  and 2# pulled slow bends.

 

Keep fittings and bends to a minimum. No kinks. Pipework supported every 0.3m, all fittings supported.  The bottle regulator and hose must be minimum 10mm bore not 8mm.

 

Test nipples on end of runs at boiler and oven.

 

This will supply with all appliances lit with  a pressure drop within 0.125 kPa.

 

E&OE

 

 

It has been pointed out to me that there is a severe error in using the 2008 ISO table in that it specifies pipe sizes by the outside diameter not the inside diameter.

The figures I have worked out are therefor incorrect.

 I will amend the sizes as follows using the 2017 ISO table which effectively is one pipe size larger.

 

 Do not use the original figures.

 

From the regulator to inside the cabin bulkhead on the port side, 12mm pipe via 2# bulkhead fittings, 2# pulled slow bends into 1# 12mm tee.

From that 12mm tee branch across the forward bulkhead and down the starboard side to the boiler, 12mm pipe via 2#  elbows and 3# pulled slow bends.

From the 12mm tee, reduced to 10mm on the end  to oven and hob via 1#  10mm tee,   2#  10mm elbows  and 2# pulled slow bends.

 

These sizes bring the pressure loss due to pipe resistance to within  the 0.125kPa allowed.

 

The isolation valves I included as otherwise it would be difficult to find any leak on either leg.  The test nipples on the ends of each leg are to satisfy an examiner that the running pressure in each leg is within the pressure loss calculation This would possibly be required if the boat was a hire or residential boat.

 

Sorry for this error, and thank you to the gent who brought the error in the published table to my attention.

 

To reiterate,  Do not use the 2008 table.  Use the 2017 amended table which specifies pipe sizes by the internal diameter and will be one size larger across the table.

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On 16/06/2022 at 10:00, Tracy D'arth said:

Ok, calculating your pipe sizes and allowing for fittings as shown, we have:

 

From the regulator to inside the cabin bulkhead on the port side, 10mm pipe via 2# bulkhead fittings, 2# pulled slow bends into 1# 10mm tee.

From that 10mm tee branch across the forward bulkhead and down the starboard side to the boiler, 10mm pipe via 2#  elbows and 3# pulled slow bends.

From the 10mm tee, reduced to 8mm on the end  to oven and hob via 1#  8mm tee,   2#  8mm elbows  and 2# pulled slow bends.

 

Keep fittings and bends to a minimum. No kinks. Pipework supported every 0.3m, all fittings supported.  The bottle regulator and hose must be minimum 10mm bore not 8mm.

 

Test nipples on end of runs at boiler and oven.

 

This will supply with all appliances lit with  a pressure drop within 0.125 kPa.

 

E&OE

 

 

It has been pointed out to me that there is a severe error in using the 2008 ISO table in that it specifies pipe sizes by the outside diameter not the inside diameter.

The figures I have worked out are therefor incorrect.

 I will amend the sizes as follows using the 2017 ISO table which effectively is one pipe size larger.

 

 Do not use the original figures.

 

From the regulator to inside the cabin bulkhead on the port side, 12mm pipe via 2# bulkhead fittings, 2# pulled slow bends into 1# 12mm tee.

From that 12mm tee branch across the forward bulkhead and down the starboard side to the boiler, 12mm pipe via 2#  elbows and 3# pulled slow bends.

From the 12mm tee, reduced to 10mm on the end  to oven and hob via 1#  10mm tee,   2#  10mm elbows  and 2# pulled slow bends.

 

These sizes bring the pressure loss due to pipe resistance to within  the 0.125kPa allowed.

 

The isolation valves I included as otherwise it would be difficult to find any leak on either leg.  The test nipples on the ends of each leg are to satisfy an examiner that the running pressure in each leg is within the pressure loss calculation This would possibly be required if the boat was a hire or residential boat.

 

Sorry for this error, and thank you to the gent who brought the error in the published table to my attention.

 

To reiterate,  Do not use the 2008 table.  Use the 2017 amended table which specifies pipe sizes by the internal diameter and will be one size larger across the table.

Bumping to the top in the hope that the OP sees it.

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