Technical Old wives tales or not

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Technical Old wives tales or not

Sturdy old British kit? I've mentioned this one before but some time ago so maybe you missed it? Back when we moved from the country back into town I saw an old vertical receiver type compressor sitting on the pavement outside a motor factor which specialized in replacement panels. I didn't have a compressor at that time and was a sometime customer so stuck my head in the door and asked what the story was with the compressor. It doesn't work so it's going to the scrappie when he can be bothered to pick it up. Can I have it? Sure, just take it away. I got it in the back of the car somehow (luckily I always buy estates but I think I was running around in the wee DAF van then) and when I got it home and stripped it down all that was wrong with it was a broken return spring on one of the "clapper" type valves in the cylinder head. I temporarily substituted a modified biro spring in it's place and it pumped perfectly. A wee while later I turned up a larger diameter pulley for the motor to make it pump faster which usefully increased it's output but it was still a small compressor on quite a large tank. It drove my air tools but only in bursts, then you had to wait for it to recharge. After I'd owned it for about 10 years I got a bit worried about the tank and decided to get it properly pressure tested. I approached a company up in Fife who I knew did this sort of thing and he asked me to read off the plate on the reciever. Ok, said I, it's a BEN - hold on, said he. is it (and he went on to describe it down to the smallest detail) Oh yes he said, I know those very well. The tanks are made of 1/4 steel plate, boiler plate mate, Never seen one anywhere even near to failing. You're wasting your money getting that tested, it'll outlive you! But it was made in 1945 I said, looking at the plate. No problem said he, seriously I wouldn't waste your money.

So I took the large bung out of the tank and used my angled mirror (like a dentists mirror) to look inside and actually it was rusty but didn't look too bad so I just left it. Quite some years later I bought "The Hooligan" (my very powerful CP air impact wrench - 1000Nm torque for undoing stuff like crank pulley bolts - but it just couldn't pump enough air for it so I bought a modern 3hp belt driven on a 100 litre tank and sold the BEN to a chap who uses it in his small agricultural repair workshop and it's still going strong as far as I know - he's never complained to me anyway.

Here's a picture of it:View attachment 417226

I made the air filter and belt guard for it - neat eh? The air filter takes an "old mini" paper element. Biggest job I ever used it for was to respray one of my Imps, which was interesting as it didn't quite keep up with the spray gun so you had to decide where you were going to stop so it had time to recover but not leave a visible join line in the paint.
I think mine was a Ben also, the pump looks the same, and the brass plaque, but it was horizontal and the tank was definitely riveted with large rivets like a steam engine boiler. I sold it to a neighbour and he sprayed his car panels with it, it was years ago but he may still even have it, though I haven't heard it for a while, it had a tendency to make lights flicker ;) . Thinking back, did yours have a sort of clutch arrangement in the back of the electric motor to help it kick in, the motor does look familiar. The one I replaced it with is an old V twin Bristol compressor, the only thing that gave problem was a big end bearing I recall and you undid a small plate to access it and it was a cheap standard type bearing. When you see all the modern Azenda Spanish type with aluminium barrels etc. scrapped because they aren't worth fixing, I suppose that is the reason by British industry went down the toilet, people only needed to buy once! I bought the Bristol one from the widow of a mechanic who ran a little workshop near us and used to do king pin reaming and other bits for people. Another thing I recall I didn't buy, but was there in tissue paper was a set of brand new Nash Metropolitan hub Caps, how many times are you going to see that? :)
 
We still have a gravity fed water system (as opposed to a combie boiler which seems to be a "must" these days) so we have a hot water tank in a cupboard on the upstairs landing. It's lovely and warm in there so I keep my welding rods at the bottom of the cupboard and MRS J has the spare towels and sheets on the shelf above. My rods seem to like it and work well.
Same here, the gas boiler was fitted a couple of years before I bought the house around 1987, daughters combi boiler has had engineers out several times and only about four years old.
 
We still have a gravity fed water system (as opposed to a combie boiler which seems to be a "must" these days) so we have a hot water tank in a cupboard on the upstairs landing. It's lovely and warm in there so I keep my welding rods at the bottom of the cupboard and MRS J has the spare towels and sheets on the shelf above. My rods seem to like it and work well.
Snap as the saying goes. Still got half a packet of cast rods in the bottom of our airing cupboard. My workshop is fairly dry so most of the other rods seem to be ok in there. Anything technical then the rods could have a night in the warm just to be sure.

I’ve just changed our Rayburn for a newer one with a bigger boiler so I think I shall be reworking the pipes in the airing cupboard. I intend to install a plate heat exchanger so I can feed the excess heat into our central heating system. My wood is virtually free so cheap heat.
 
Snap as the saying goes. Still got half a packet of cast rods in the bottom of our airing cupboard. My workshop is fairly dry so most of the other rods seem to be ok in there. Anything technical then the rods could have a night in the warm just to be sure.

I’ve just changed our Rayburn for a newer one with a bigger boiler so I think I shall be reworking the pipes in the airing cupboard. I intend to install a plate heat exchanger so I can feed the excess heat into our central heating system. My wood is virtually free so cheap heat.
Curious Ian I have a room heater, coal fired and wanted to run a similar one in tandem with my gas central heating as the room heater is on from November till March, but I couldn't see an easy way to run the radiators without causing issues with the gas boiler pump system.
 
I think mine was a Ben also, the pump looks the same, and the brass plaque, but it was horizontal and the tank was definitely riveted with large rivets like a steam engine boiler. I sold it to a neighbour and he sprayed his car panels with it, it was years ago but he may still even have it, though I haven't heard it for a while, it had a tendency to make lights flicker ;) . Thinking back, did yours have a sort of clutch arrangement in the back of the electric motor to help it kick in, the motor does look familiar. The one I replaced it with is an old V twin Bristol compressor, the only thing that gave problem was a big end bearing I recall and you undid a small plate to access it and it was a cheap standard type bearing. When you see all the modern Azenda Spanish type with aluminium barrels etc. scrapped because they aren't worth fixing, I suppose that is the reason by British industry went down the toilet, people only needed to buy once! I bought the Bristol one from the widow of a mechanic who ran a little workshop near us and used to do king pin reaming and other bits for people. Another thing I recall I didn't buy, but was there in tissue paper was a set of brand new Nash Metropolitan hub Caps, how many times are you going to see that? :)
No Mine didn't have anything like that clutch arrangement on the motor. I actually had a spare motor for it too. They both had large capacitors and back in those days I was really ignorant about mains electric motors. It failed to kick in one day when I was using the spray gun - which actually turned out to be a fault with the pressure switch but I was convinced it was something to do with the motor so, in my stupid ignorance, I started continuity checking with my rather nice AVO Minor meter. Of course, the charge in the capacitors ruined the meter which was set on Ohms for the continuity checking. I was so upset when I realized what I'd done it wasn't for several days that I realized I could have done myself a serious injury! I've never owned such a quality piece of electrical kit since.

The compressor which replaced it, no doubt made in China? is this one:

P1050752.JPG


Which I run at 125 psi claims 14 cfm air delivery (so likely around 9, maybe 10 cfm free air? (it can do 150 psi but I keep it down to that for reliability and long life) it drives the "Hooligan" very effectively on nice large diameter hoses. I doubt if it'll last anything like as long as the BEN has but It'll outlive me so I don't care! It runs on my old fused garage 13 amp spur but trips the RCD circuits if I try to run it from one of the house sockets. Going to get a "proper" 16 amp supply wired in the garage for it when my friend's electrician son can find the time to do it for me and I'll eb able to run the welders from that supply when needed too. At present I have to be careful not to hook up anything else if the compressor is on as it pulls quite some current on start up. By the way, just in case anyone is thinking of buying this brand, I'm very pleased with it and with the backup from UKHS from whom I bought it. When it arrived the big compressor pulley was bent so I rang them up and they immediately offered to send another. As it was only the pulley which was damaged and I worried if they sent another compressor complete that it might actually be even worse damaged, I asked if they could send just the pulley. It arrived in two days flat. I rang to thank them for their service and was told they hold comprehensive spares so if I ever need other parts just to ring. The compressor has run faultlessly for several years now but doesn't run every day. probably averaging out at about one week in every five or six in terms of total hours (it tends to run for quite a while when I'm doing a "big" job and then lie idle for a while.)
 
Same here, the gas boiler was fitted a couple of years before I bought the house around 1987, daughters combi boiler has had engineers out several times and only about four years old.
Same story here Mike, both my boys have combies. the older boy doesn't have much trouble but did need a few visits just after it was installed, seems to have settled down now, but we'll see? younger boy has had ongoing problems with the water pressure dropping and needing topped up roughly every two weeks. Got to be a leak somewhere? but no-one can find it. Last time the plumber visited he put a leak sealer in the system. We'll just have to see if that "cures" it, but long term I'd be happier if they just found the leak. They never had a moment's bother with the old baxi back boiler it replaced.
 
Curious Ian I have a room heater, coal fired and wanted to run a similar one in tandem with my gas central heating as the room heater is on from November till March, but I couldn't see an easy way to run the radiators without causing issues with the gas boiler pump system.
I don’t intend to run the pump from the Rayburn at the same time as the central heating pump as the Rayburn should provide enough heat on its own so should be quite a simple bit of plumbing. I’ve a redundant section of 22 mm from the central heating circuit that I can access easily so I will investigate feeding the heat from the Rayburn in at that point.

I you want to add the heat from your room heater and still run the gas it might be a bit more involved. I expect you would need to feed it in at the gas boiler before any zone valves. (Domestic Hot Water or rads). Presumably you have two systems, pressurised and gravity?
 
No Mine didn't have anything like that clutch arrangement on the motor. I actually had a spare motor for it too. They both had large capacitors and back in those days I was really ignorant about mains electric motors. It failed to kick in one day when I was using the spray gun - which actually turned out to be a fault with the pressure switch but I was convinced it was something to do with the motor so, in my stupid ignorance, I started continuity checking with my rather nice AVO Minor meter. Of course, the charge in the capacitors ruined the meter which was set on Ohms for the continuity checking. I was so upset when I realized what I'd done it wasn't for several days that I realized I could have done myself a serious injury! I've never owned such a quality piece of electrical kit since.

The compressor which replaced it, no doubt made in China? is this one:

View attachment 417228

Which I run at 125 psi claims 14 cfm air delivery (so likely around 9, maybe 10 cfm free air? (it can do 150 psi but I keep it down to that for reliability and long life) it drives the "Hooligan" very effectively on nice large diameter hoses. I doubt if it'll last anything like as long as the BEN has but It'll outlive me so I don't care! It runs on my old fused garage 13 amp spur but trips the RCD circuits if I try to run it from one of the house sockets. Going to get a "proper" 16 amp supply wired in the garage for it when my friend's electrician son can find the time to do it for me and I'll eb able to run the welders from that supply when needed too. At present I have to be careful not to hook up anything else if the compressor is on as it pulls quite some current on start up. By the way, just in case anyone is thinking of buying this brand, I'm very pleased with it and with the backup from UKHS from whom I bought it. When it arrived the big compressor pulley was bent so I rang them up and they immediately offered to send another. As it was only the pulley which was damaged and I worried if they sent another compressor complete that it might actually be even worse damaged, I asked if they could send just the pulley. It arrived in two days flat. I rang to thank them for their service and was told they hold comprehensive spares so if I ever need other parts just to ring. The compressor has run faultlessly for several years now but doesn't run every day. probably averaging out at about one week in every five or six in terms of total hours (it tends to run for quite a while when I'm doing a "big" job and then lie idle for a while.)
I am starting to worry on two fronts, one is the state of my equipment compared with yours and the other is the state of my mind, just looked in the garage, the compressor I am using that I thought was a Bristol for some reason is an HPC and the funny clutch arrangement I thought was on my old BEN compressor is actually on this one lurking under one of my benches.:confused:
 

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I am starting to worry on two fronts, one is the state of my equipment compared with yours and the other is the state of my mind, just looked in the garage, the compressor I am using that I thought was a Bristol for some reason is an HPC and the funny clutch arrangement I thought was on my old BEN compressor is actually on this one lurking under one of my benches.:confused:
Crazy old man Mike? join the gang, there's plenty more of us!
 
I don’t intend to run the pump from the Rayburn at the same time as the central heating pump as the Rayburn should provide enough heat on its own so should be quite a simple bit of plumbing. I’ve a redundant section of 22 mm from the central heating circuit that I can access easily so I will investigate feeding the heat from the Rayburn in at that point.

I you want to add the heat from your room heater and still run the gas it might be a bit more involved. I expect you would need to feed it in at the gas boiler before any zone valves. (Domestic Hot Water or rads). Presumably you have two systems, pressurised and gravity?
Yes, ideally the gas boiler central is on a timer and just has the basic circulation pump, water is gravity fed from attic , no pressurised system/combi etc.
I thought that as I keep the room heater on continuous Nov. to March if it was similar model with back boiler topping up the radiator gas central heating it would be warming the radiators in addition to when the gas comes on. I find the room heater warms the down stairs room plus the one above via the chimney breast transferring heat as it is and if in addition it was adding a little to the radiators so much the better.
 
Nothing wrong with a bit of "overkill" it's often why an older vehicle can be relatively cheaply brought back to life and is strongly to be recommended with the old horticultural machines I mess about with.

Cebora - pronounced Chebora I'm told? My MIG is a Cebora Pocket Turbo 130. It's the same machine rebadged as Snap On and was sold out of their vans (for more money) and an excellent machine it is too, had mine for a long time and the only problem I've had is with the switch in the handle itself which controls the wire feed, It's not a very robust design and needs to be dismantled about every 2 years and have it's contact faces cleaned with some fine grade emery, then it's good to go again 'till the next time. The rest of the machine has never even "blinked"! Can't remember when I bought it but I've had it for a long time.

The other excellent welder I have is the first one I ever bought. It's an SIP Topweld 140 stick welder. bought in the early 70's. I've made and repaired shed loads of stuff with it. Welding up cultivator chassis, making my own small (5ft x 3ft) unbraked trailer and many other projects. The only problem I've come across with it is that because it's a machine at the cheaper end of the price range (I was an impoverished and ignorant youngster when I bought it) it's transformer windings are aluminium. If I was buying again I'd go for one with copper wires. In fact the aluminium core works very well but has a basic flaw. I found this out one day when welding with it and found it getting increasingly difficult to strike the arc. This got worse until one day I gave up using it, thinking it was knackered, and parked it under my workbench where it stayed for quite a number of years. Luckily I had access to welding gear at work so just used that. Then when I started doing the evening welding classes I found that many of my students were wanting to learn on machines like it - I encouraged people to bring their own machine in with them and learn on their own machine because these cheaper machines can be quite different to use, especially regarding striking the arc which depends on having a good open circuit voltage and can be quite marginal on really cheap machines. So, as some students hadn't yet bought their machines, I hauled the SIP out from under the bench and set about finding what was wrong with it. It turned out to be very simple. A friend at work who was a professional welder (north sea pipes) helped me dismantle it and we found the connection between the aluminium windings - which were formed into "eyes" by bending the wire round - and the steel output terminals was poor due to a build up of corrosion ( I now know this was an electrolytic reaction between the aluminium and steel of the terminal. I gave them a light clean up and made sure the connections were tight and it worked probably better than it ever had even when new! I now find that a very light clean up every couple of years and a light coat of ceramic anti seize completely cures this problem. I've since resurrected a few of these welders with this same problem and I'm always keeping my eyes open at autojumbles for cheap machines because often that's all they need to completely restore them to full usability again.

Don't know how many of you are into doing stick welding? but in case it's useful some of the more common problems my beginners had were:

Using the "wrong" rods. You need to be using a good quality general purpose, all position, RUTILE rod. Buy from a welding supplier who will be able to advise you on what's best and probably be cheaper too.

Don't expect too much from the machine. These small machines are all air cooled and many don't even have a fan. Mine didn't and would overheat and cut out when welding heavier gauge stuff. All but the cheapest will have a thermal overload which cuts it out if the windings get too hot. Then you have to wait for it to cool down before it'll work again - could be half an hour - but if you just start welding again right away, within a very short time it'll get to hot and cut out again because it wasn't fully cold when you restarted. By the way, these cut outs can fail so if your machine was working fine and suddenly cuts out and then, after waiting for it to cool, it still won't work all it may need is a new cut out which is cheap and easy to change.

Don't expect it to give you a long weld time with thicker rods. My machine - SIP topweld 140 - claims to be able to handle 3.5mm rods, and it will, just, for a very short time. I find it much better to accept that it works well with 2.5 (and smaller if you get good at it - small rods are much more difficult to work with). I've also installed a cooling fan into the back of it's cover and blanked off the rear louvres so that air is pulled in over the transformer core from the front and expelled through the fan at the back. It now very rarely, if ever, cuts out when using 2.5 rods. As a little guidance 2.5 rods are ideal for welding stuff like angle iron and plate. You're not going to weld car bodywork with it. Even with a 1.6 rod you've got to be very good to weld stuff like wings and sills. better to buy a MIG if that's what you want to do. Unless you're only going to use it very occasionally, it's worth splashing a little more cash for one with a cooling fan and probably, as it's going to be a bit more "uprange" it'll have copper windings too.

Electrical supply. Don't expect to be able to take the welder down to the bottom of the garden, plug it into your power tool extension lead, and expect it to work. It'll "fool" you into thinking it's working because when you switch it on it's lights will light up and the core will probably "humm" but it won't be able to pull the current it needs to weld and, although you might get a spark, you'll find you can't strike the arc. I have a 15 meter 2.5 wire size, 3 core extension which, when plugged into the welder's own supply cable allows me to work anywhere I need in my workshop and that's probably about as far as I think I could stretch it. I would not use this extension unless needed though and plug the machine in on it's own cable wherever possible. So you need nice thick cable size and not too long otherwise the current drop in the wire itself will stop it working. The shorter the better is the way to go.

I'm sure there's much more I could talk about but the above is agood starting point. I find welding very satisfying to do and it's amazing what you can do once you've mastered the basics. You do need to learn some technique though and a short course will rapidly bring you up to speed whereas trying to just muddle along on your own will take much longer. Don't think these wee machines are "toys". you can easily hurt yourself and others if you're not careful but also you can make and mend some really ambitious stuff. My biggest achievement was to build my own trailer. 95% of it being welded up with the SIP stick welder with only a few little brackets added later with the MIG. I'm very proud of it so here's a picture for you all to go "awe" over. It's loaded up with my gardening gear ready to go off for a day's happy gardening at my boy's house :

View attachment 417183
Mines a cebora, it was a great machine, had to replace the gun and line and it worked brilliantly for a further 3yr, until the line feed went, no longer supplied, and those cheap Chinese’universal’ line feeders are not worth the postage, and that was free
No Mine didn't have anything like that clutch arrangement on the motor. I actually had a spare motor for it too. They both had large capacitors and back in those days I was really ignorant about mains electric motors. It failed to kick in one day when I was using the spray gun - which actually turned out to be a fault with the pressure switch but I was convinced it was something to do with the motor so, in my stupid ignorance, I started continuity checking with my rather nice AVO Minor meter. Of course, the charge in the capacitors ruined the meter which was set on Ohms for the continuity checking. I was so upset when I realized what I'd done it wasn't for several days that I realized I could have done myself a serious injury! I've never owned such a quality piece of electrical kit since.

The compressor which replaced it, no doubt made in China? is this one:

View attachment 417228

Which I run at 125 psi claims 14 cfm air delivery (so likely around 9, maybe 10 cfm free air? (it can do 150 psi but I keep it down to that for reliability and long life) it drives the "Hooligan" very effectively on nice large diameter hoses. I doubt if it'll last anything like as long as the BEN has but It'll outlive me so I don't care! It runs on my old fused garage 13 amp spur but trips the RCD circuits if I try to run it from one of the house sockets. Going to get a "proper" 16 amp supply wired in the garage for it when my friend's electrician son can find the time to do it for me and I'll eb able to run the welders from that supply when needed too. At present I have to be careful not to hook up anything else if the compressor is on as it pulls quite some current on start up. By the way, just in case anyone is thinking of buying this brand, I'm very pleased with it and with the backup from UKHS from whom I bought it. When it arrived the big compressor pulley was bent so I rang them up and they immediately offered to send another. As it was only the pulley which was damaged and I worried if they sent another compressor complete that it might actually be even worse damaged, I asked if they could send just the pulley. It arrived in two days flat. I rang to thank them for their service and was told they hold comprehensive spares so if I ever need other parts just to ring. The compressor has run faultlessly for several years now but doesn't run every day. probably averaging out at about one week in every five or six in terms of total hours (it tends to run for quite a while when I'm doing a "big" job and then lie idle for a while.)
same here, so far can’t fault it and service seems very good…agree that it needs the larger airlines
 
Yes, ideally the gas boiler central is on a timer and just has the basic circulation pump, water is gravity fed from attic , no pressurised system/combi etc.
I thought that as I keep the room heater on continuous Nov. to March if it was similar model with back boiler topping up the radiator gas central heating it would be warming the radiators in addition to when the gas comes on. I find the room heater warms the down stairs room plus the one above via the chimney breast transferring heat as it is and if in addition it was adding a little to the radiators so much the better.
With your room heater being solid fuel you would also need some system to absorb the heat in the event of a power cut.
Coil in your immersion tank or its own rad/ rads upstairs perhaps.
 
With your room heater being solid fuel you would also need some system to absorb the heat in the event of a power cut.
Coil in your immersion tank or its own rad/ rads upstairs perhaps.
Yes, it's not like you can quickly switch off the heat from a coal fire. I didn't want to have separate extra radiators though.
Your suggestion of a separate heating coil from the coal fire would heat the immersion tank for hot water like the old back boilers open fires had when I was young, but won't make much difference to the radiators around the house.
I have pondered the problem for some time trying to find the ideal solution without involving extra pumps and electronic valves shutting off different circuits.
 
Yes, it's not like you can quickly switch off the heat from a coal fire. I didn't want to have separate extra radiators though.
Your suggestion of a separate heating coil from the coal fire would heat the immersion tank for hot water like the old back boilers open fires had when I was young, but won't make much difference to the radiators around the house.
I have pondered the problem for some time trying to find the ideal solution without involving extra pumps and electronic valves shutting off different circuits.
 
Yes, it's not like you can quickly switch off the heat from a coal fire. I didn't want to have separate extra radiators though.
Your suggestion of a separate heating coil from the coal fire would heat the immersion tank for hot water like the old back boilers open fires had when I was young, but won't make much difference to the radiators around the house.
I have pondered the problem for some time trying to find the ideal solution without involving extra pumps and electronic valves shutting off different circuits.
How about a coil in your tank, you would need a normally open motorised valve controlled by a tank stat to save overheating and keep a bit of capacity for the room heater to heat when the ch pump and boiler is on.
A second circuit linked into the central heating circuit that hopefully would run a rad or two upstairs. You would need a normally open motorised valve that is linked to the pump power to close it when the pump turns on. Otherwise as have no doubt considered, you might get reverse flow through the room heater assuming the pump would overcome the convection flow.
Not a simple solution and you would need a couple of valves but no extra pump or heat exchanger needed.
Would you change your coal fire to a dedicated wood burner or perhaps a multi fuel? Regs are changing I believe.
 
How about a coil in your tank, you would need a normally open motorised valve controlled by a tank stat to save overheating and keep a bit of capacity for the room heater to heat when the ch pump and boiler is on.
A second circuit linked into the central heating circuit that hopefully would run a rad or two upstairs. You would need a normally open motorised valve that is linked to the pump power to close it when the pump turns on. Otherwise as have no doubt considered, you might get reverse flow through the room heater assuming the pump would overcome the convection flow.
Not a simple solution and you would need a couple of valves but no extra pump or heat exchanger needed.
Would you change your coal fire to a dedicated wood burner or perhaps a multi fuel? Regs are changing I believe.
No simple solution what ever I do.
Regarding wood burners etc. in the middle of town so smokeless fuel preferred, no cheap source of dry logs for me and finally with my current set up on low I only have to top coal twice a day and empty ash once. I know there is very little ash with wood but it does tend to need topping up more often than anthracite.
One thing I will not be doing is installing a heat pump;)
 
No simple solution what ever I do.
Regarding wood burners etc. in the middle of town so smokeless fuel preferred, no cheap source of dry logs for me and finally with my current set up on low I only have to top coal twice a day and empty ash once. I know there is very little ash with wood but it does tend to need topping up more often than anthracite.
One thing I will not be doing is installing a heat pump;)

I thought about it after I posted and I guess that was similar to what you were thinking anyway, separate circuits, valves etc. so sorry if I was stating the obvious.
Agreed on the heat pump, air source one anyway.
Probably the best and cheapest solution is the one you already have.

My next project is to make a dedicated wood grate for my Rayburn as it came with a multi fuel one which lets the ash through too quickly. I could buy one but where’s the fun in that.
 
In previous life I had a PowerMax boiler. This was effectively a hot water cylinder with a fire box across the bottom with heat tubes going through to a cap on the top. A fan fed gas burner fired into the firebox and fumes were taken away from the top. The huge thermal store made it extremely efficient. Radiators were simply tapped from top side via pump with the return fed into the bottom. There was no heat exchange coil on the radiator circuit. Hot water was provided by a high performance copper coil in the top of the cylinder. You got instant mains pressure hot water through that coil without the rattle of a big inefficient burner to flash heat the water. Plumbers hated them because they refused to read the instructions and they were not getting kickbacks to sell Bosh, Glowbum or whatever brand of combi boiler was the latest rave.

It was intended to be fitted upstairs so there would be no thermal syphon effect. Mine was fitted downstairs with an electric valve. The gas burner fired on heat demand, so you "could" fit a second heat source meaning the gas would fire less often. Unfortunately that would be against the gas regulations.

You an get a similar effect with a thermal store cylinder again you need a high performance oil in the top for heating hot water. Some have two coils so you can run a shower and not have it doing annoying stuff when someone opens a tap elsewhere in the house. A pair of side tappings are fed to the gas boiler. A second set can be connected to any other heart source eg solid fuel back burner. The mass of water in the cylinder mess the flows dont affect each other but they do both need a pump and you need another pump for the radiators which also have their own side tappings and pump.

The very top of the cylinder is vented into a feed and expansion tank (bigger is better if you have solid fuel). Cold feed drops into the bottom of the cylinder at the drain tapping.

Does it work? I fitted one at my mothers house (though it was gas only) and halved her gas bills. It stopped the boiler cycling on/off every 20 seconds and dramatically improved its efficiency.
 
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