Heating Dilema.

[warlock]

Hi All,

 

Here's a dilema for you. My boat Col has a stove with a back boiler and 2 rads attached. The rads are heated either by the stove or an Alde. Currently the Alde has been decommisioned because there's a gas leak. According to the stickers put on by the engineers it's not been serviced since '95, that's when Col was built so it's been neglected somewhat.

Anyhoo, on top of that I think the stove is on it's last legs. I've been looking around and I can get a nice stove, without a back boiler for 2-300 bills. So my q. is, should I...

 

A: Get one. Rip out the rads and Alde and replace them with an eco-fan.

B: Replace the stove with a back boiler model and get the Alde serviced.

C. Replace the stove with a back boiler model and try and find a pump to pump the water round the system and rip out the Alde.

D. Non of the above and be open to suggestions from you lot.

 

Hope that makes sense...What would you all do?

 

Cheers, Warlock.

[pwl]

Well, our just acquired boat has an antique Aldi on it and we plan a small stove and a Webasto. An Alde works well but eats gas. OTOH, you already have it and a replacement costs £££££

 

P

[steelaway]

Hi All,

 

Here's a dilema for you. My boat Col has a stove with a back boiler and 2 rads attached. The rads are heated either by the stove or an Alde. Currently the Alde has been decommisioned because there's a gas leak. According to the stickers put on by the engineers it's not been serviced since '95, that's when Col was built so it's been neglected somewhat.

Anyhoo, on top of that I think the stove is on it's last legs. I've been looking around and I can get a nice stove, without a back boiler for 2-300 bills. So my q. is, should I...

 

A: Get one. Rip out the rads and Alde and replace them with an eco-fan.

B: Replace the stove with a back boiler model and get the Alde serviced.

C. Replace the stove with a back boiler model and try and find a pump to pump the water round the system and rip out the Alde.

D. Non of the above and be open to suggestions from you lot.

 

Hope that makes sense...What would you all do?

 

Cheers, Warlock.

 

 

Hi There

IMHO

If live on it I think you're better with two alternatives for heating - So Choice 'B'

If you dont then - Choice 'C'

It would be a shame to remove the existing central heating.

 

Alex

[warlock]

Cheers so far peeps. Yeah I do already have an Alde, I've heard they roar through gas but it's there. The only thing is, with it being 10+ years old is it worth servicing? It may well be on it's last legs anyway.

BUT and it is quite a large but. I think Col is an ex hire boat. If he is then surely the stickers are lying because surely the Alde would have to be regularly serviced to comply with the BSS/RCD issues.

[Yoda]

Keep the stove and use it for the time being. Fix and service the Alde. Then buy new Alde and Eco fan and be happy.

[Keeping Up]

Go for option B if you can.

 

If you are heating the boat only by Alde, they use quite a lot of gas. Similarly if you are heating the boat only by solid fuel stove, they use quite a lot of solid fuel - which is cheap if you are collecting and burning free wood but can be nearly as expensive as the gas option if you are using bought-in smokeless fuel AND you're keeping the whole boat warm with it. A lot of people compare the cost of heating the whole boat by Alde versus the cost of heating just the lounge by solid fuel, and of course the solid fuel looks a lot cheaper.

 

Having a mix of solid fuel and gas (with appropriate thermostatic controls) is an excellent option.

 

The boiler may have many years of use left in it. Certainly there is no BSS requirement for the boiler ever to be serviced on a private boat, but I don't know about hire-boats.

[warlock]

Well, the stoves chimney is in a bad way..cheap and easy-ish to repair I know but also one of the hinge lugs has snapped too. Is that easy to repair? I've tried various glues but they can either take the weight of the door but not the heat or take the heat but not the weight. I'm not sure what it's made of or what make..sorry.

 

I'd like to keep the Alde for 2 reasons.

A. It has the pump that pumps the water round the rads.

B. Quick heat when I get home late from work and it's freezing.

[dor]

If the Alde is a 2928 (i.e. has a balanced flue), I would remove the burner unit and send it off to Alde for a service. Cost is around £70, plus any parts that are needed (probably needs a new pilot jet). You can download the service sheet which tells you how to remove the burner unit from the alde website.

 

Fit a new solid fuel stove, without the back boiler for simplicity and price, unless you feel like paying the extra.

 

You will find that the solid fuel stove will provide 90% of your heating, and the alde will only be used to boost the heating until the stove gets going, or for a quick blast first thing in the morning to get the bathroom/bedroom warm. This will mean that the running costs of the alde (which incidently are not much higher than a diesel burner these days) will be reasonably manageable.

 

If you want central heating, you have to be prepared to pay for it - no different in a house. But the cost doesn't have to be ridiculous, and provided you only use the central heating as a backup to the stove the costs will be reasonable.

[bottle]

Hi Warlock

 

Option 'B' this gives you two forms of heating and if one fails, you then have the other, very handy if it's cold.

[Chris Pink]

Could you keep the back boiler and get a replacement for the stove? also if it's a reputable make you might be able to get the bits to fix it, or find a welder.

 

The Alde should be serviceable, as long as you can still get the bits, its got to be cheaper than replacing it.

[chris w]

........... the running costs of the alde (which incidently are not much higher than a diesel burner these days) will be reasonably manageable.

 

Dor

 

With respect, I can't agree with your statement (unless I am grossly missing something)

 

 

The Gross Calorific Value of Propane is 50MJ.kg^-1

 

13kg therefore contains 650MJ = 650 x 10³ KW.secs

 

An Alde has a heat output of 5.4KW at 80% efficiency max (probably closer to 70%, but let's use 80%) which means that the heat input is 6.75KW, so 13kg of propane will last:

 

650 x 10³ /6.75 /3600 hours = 27 hours

 

At £20 for a propane refill, that equates to a running cost of 20/27 = 74 pence/hour

 

My Webasto heater (with exactly the same heat output) consumes 0.25 litres of diesel per hour. At 58 pence per litre, for diesel, that equates to 14.5 pence per hour.

 

 

This means the Webasto is currently a factor of over 5 times cheaper to run than an Alde.

 

 

Even if diesel rises to £1.20 a litre after November this year, as predicted, running a Webasto will still be 2.5 times cheaper to run than an Alde.

 

Plus, one doesn't have to lug heavy gas bottles around, and find a retailer of gas every few days either.

 

One even feels it, subjectively, in that it always seems that however long one runs the Webasto, the diesel level never drops noticeably

 

Chris

Edited February 21, 2008 by chris w

[Phoenix_V]

Dor

 

With respect, I can't agree with your statement (unless I am grossly missing something)

The Gross Calorific Value of Propane is 50MJ.kg^-1

 

13kg therefore contains 650MJ = 650 x 10³ KW.secs

 

An Alde has a heat output of 5.4KW at 80% efficiency max (probably closer to 70%, but let's use 80%) which means that the heat input is 6.75KW, so 13kg of propane will last:

 

650 x 10³ /6.75 /3600 hours = 27 hours

 

At £20 for a propane refill, that equates to a running cost of 20/27 = 74 pence/hour

 

My Webasto heater (with exactly the same heat output) consumes 0.25 litres of diesel per hour. At 58 pence per litre, for diesel, that equates to 14.5 pence per hour.

This means the Webasto is currently a factor of over 5 times cheaper to run than an Alde.

Even if diesel rises to £1.20 a litre after November this year, as predicted, running a Webasto will still be 2.5 times cheaper to run than an Alde.

 

Plus, one doesn't have to lug heavy gas bottles around, and find a retailer of gas every few days either.

 

One even feels it, subjectively, in that it always seems that however long one runs the Webasto, the diesel level never drops noticeably

 

Chris

 

 

Your maths are about right for the Alde BUT

There are various gas buying schemes and it is possible to buy an 11kg bottle of flogas (as I do) for about £13 delivered

Aldes website quotes 420g/hour on full power so that equates to about 10kg in 24 hours or just under 50 pence per hour.

 

Looking at Webastos I am not sure I follow your calculation, according to Webastos website the Thermo top c for instance would appear to be a comparable heater with 5.2kw output uses .59 litres diesel per hour ie about 36 pence per hour, so the difference is not so great. Drip feed stoves are less efficient.

 

Diesel heaters such as the Webasto use about 3.5 amps/hr electricity (again taken from the website) and have known isues with reliability and require regular servicing.

 

The fuel occupies less space but it is easier to get bottles delivered to a boat than diesel and regularly changing bottles is no more onerous than humping bags of coal.

 

So I dont think the choice is so clear cut

 

I should be interested to hear from anyone who has used both as I am currently looking at what heat to install and at the moment veering towards coal/multifuel stove for comfort and economy backed by an Alde.

[Ernie]

I should be interested to hear from anyone who has used both as I am currently looking at what heat to install and at the moment veering towards coal/multifuel stove for comfort and economy backed by an Alde.

We have a solid fuel stove (did have a diesel stove but dumped it - literally) and one of the tall thin Alde’s.

 

We use the stove for general boat heating – it has not been out since October. We use the Alde for heating water for washing and showering – it’s on for around one hour every day when we have not been cruising. A 13kg bottle of gas lasts us just over a month in the winter but that includes running the cooker as well so it is difficult to determine how much is used by the Alde. We occasionally turn on the radiator in the bathroom and bedroom and fire up the Alde to heat them. We have only needed to do this when the outside temperature drops below around minus 2 – probably only half a dozen times this winter. It is nice to have the Alde as a backup heat source.

 

In the summer when we are cruising almost every day, a bottle of gas last over two months as the engine does most of the water heating.

[smileypete]

An Alde has a heat output of 5.4KW at 80% efficiency max (probably closer to 70%, but let's use 80%) which means that the heat input is 6.75KW

 

...

 

My Webasto heater (with exactly the same heat output) consumes 0.25 litres of diesel per hour.

 

I think you're grossly missing something Chris, why not do the math for your heater and you may find out.

 

In any case an Alde should be used on a thermostat, which invalidates a straight comparison somewhat.

 

Using a thermostat it basically comes down to the cost of the fuel in energy terms and the efficiency of the heater.

 

Edit:

Propane at £20 for a 13kg bottle is around 12p/kWh.

Taxed diesel at £1.10 a litre is around 10p/kWh.

 

So there's not a lot in it unless a separate tank for untaxed diesel is used.

 

cheers,

Pete.

Edited February 23, 2008 by smileypete

[chris w]

Your maths are about right for the Alde BUT

There are various gas buying schemes and it is possible to buy an 11kg bottle of flogas (as I do) for about £13 delivered

Aldes website quotes 420g/hour on full power so that equates to about 10kg in 24 hours or just under 50 pence per hour.

 

Looking at Webastos I am not sure I follow your calculation, according to Webastos website the Thermo top c for instance would appear to be a comparable heater with 5.2kw output uses .59 litres diesel per hour ie about 36 pence per hour, so the difference is not so great. Drip feed stoves are less efficient.

 

Diesel heaters such as the Webasto use about 3.5 amps/hr electricity (again taken from the website) and have known isues with reliability and require regular servicing.

 

The fuel occupies less space but it is easier to get bottles delivered to a boat than diesel and regularly changing bottles is no more onerous than humping bags of coal.

 

So I dont think the choice is so clear cut

 

I should be interested to hear from anyone who has used both as I am currently looking at what heat to install and at the moment veering towards coal/multifuel stove for comfort and economy backed by an Alde.

 

I did make a couple of errors:

 

1. The consumption of 0.25l/hr of diesel for the Webasto is at HALF heat (ie: 2.5KW output). However, this is the mode in which the Webasto runs after its initial heating up of the water from ambient to 62degC which takes 20 minutes and during that period, ONLY, does use diesel at a rate of 0.5l/hr. (ie: about 0.2 litres actually consumed)

 

However, after that, all consumption is at a rate of 0.25l/hr while it heats the water to 72degC.

 

2. The actual consumption though is even lower because for about 50% of the time, the Webasto is in "idle mode" whereby it turns off the burner while it lets the water temperature drop from 72degC to 62degC after which the Webasto comes on again at half power to take the water back up to 72degC and so on. So my figure of 14.5 pence per hour was an overestimate because I had overlooked the idle time. Thus, the running cost difference between the Alde and the Webasto is even greater.

 

The servicing issues to which you refer are applicable to Eberspaechers not Webastos, which are easily dismantled and serviced by the owner. I don't know what you mean by "they consume 3.5A/hr". There is no such measurement as amps/hr.

 

Even in its normal half power mode, my Webasto runs 3 radiators and a 60 litre calorifier and the boat is toasty warm.

 

BTW, with the new Alde, and according to their website, there must be absolutely NO copper whatsoever in the heating circuit anywhere or else aggresive corrosion will take place. This is because the new Alde's use aluminium chambers. Where are you going to get an aluminium calorifier?

 

Chris

Edited February 23, 2008 by chris w

[dor]

Where are you going to get an aluminium calorifier?

 

You don't need to. As has often been pointed out, you can use a stainless steel one (Alde recommend one), which is not a lot more in cost than an equivalent copper one.

 

And how does the price of diesel boilers compare to the Alde?

Edited February 23, 2008 by dor

[Phoenix_V]

You don't need to. As has often been pointed out, you can use a stainless steel one (Alde recommend one), which is not a lot more in cost than an equivalent copper one.

 

And how does the price of diesel boilers compare to the Alde?

 

 

The Old Alde is apparently still available and considerably cheaper than the new one, I gather the new one is slightly more efficient but uses more electricity so is there really any great advantage in going for the new one?

[chris w]

And how does the price of diesel boilers compare to the Alde?

 

List price of both is ~£1200, though I have seen brand-new warranted Webastos on Ebay for £600 occasionally.

 

Chris

[Ernie]

650 x 10³ /6.75 /3600 hours = 27 hours

At £20 for a propane refill, that equates to a running cost of 20/27 = 74 pence/hour

Chris

Chris,

 

Are you assuming that the Alde burner is firing all the time?

The reality is that it only fires when there is a heat demand from the boiler thermostat which of course is dependant on such things as ambient boat temperature and calorifier water temperature. The Alde works the same way as any other central heating system.

[chris w]

Chris,

 

Are you assuming that the Alde burner is firing all the time?

The reality is that it only fires when there is a heat demand from the boiler thermostat which of course is dependant on such things as ambient boat temperature and calorifier water temperature. The Alde works the same way as any other central heating system.

 

Yes I understand that Ernie, so I assumed 100% duty cycle for both units to get a relative cost of running. It does seem that the typical Alde user is changing their gas bottle every 3-4 days based on stuff on here and my asking aroud my marina. Even ignoring the maths above, that equates to around £30-£40 per week running costs, for a liveaboard, with regard to the Alde.

 

Chris

[dor]

List price of both is ~£1200, though I have seen brand-new warranted Webastos on Ebay for £600 occasionally.

 

The going rate for the new Alde boiler is about £1000 including the full fitting kit. I think the older type can be found for under £700. Maybe even less occasionally on Ebay.

[saltysplash]

I dont understand what all the fuss is about

 

 

We have a 60ft boat with squirell/backboiler feeding 1 rad using gravity/convection system.......boats too bloody warm if left in Swmbo's hands. Water is heated either via immersion or engine or Paloma...normally paloma unless out and about.

 

13k gas bottle lasts us appx 1 month coal for the fire varies depending on the outside temp.