openspaceman

Last I heard it was 31k tonnes/month when the boilers aren't broke down.

What's the difference between a tracked a340 and a430? Just 2" of opening in height?

We ran some trials quartering small dimension sc from coppice and it moved less and was more stable than oak. At the same time we were exporting larger stuff to Portugal. They seemed to through saw it and then glue it in random widths for table tops, drawer bottoms etc. At about the same time it was in vogue (expensively end jointed) for a couple of gridshells. I don't know what triggers shake in sc but if the bark is still smooth we didn't get shake. SC is one of the most reliable to re grow from stump at any size/age. I see sc posts and stakes I put in 30 years ago and still good, even cca treated stuff didn't last long because the treatment was seldom correct, only pine absorbed it well. Even then if overdosed it weakened the wood. I worry about the new stuff, organic copper salts, I cannot understand why nitwork rail specify it for bridge crossing timbers when creosote is proven. I here many complaints about this from the now defunct fencing sawmill of a company near here where garden fences haven't lasted 5 years.

Still don't know what you would describe her as. I was recently corrected for calling a blue eyed inuit type a husky! Local arb contractor here had one called varna after the saw. As to harness would it be wrong to train my daughter's dalmation cross to harness? And what sort of harness?

Sorry the above is wrong, I meant parallel, meaning the pump won't run unless one of the zone valves is open.

It looks like this was answered because they were to be spar trees. However back in 1974 when I started for EFG the two old guys who had been felling during the war swore it was necessary to top big conifer because the air resistance of the top caused it to snap and fall vertically onto the feller, in much the same way Fred Dibnah's chimney stacks broke up before hitting the ground. Working in Surrey I think the tallest tree I ever felled was a 123 ft Douglas and that was no problem.

You could just put another in parallel and join the bottoms, there is an issue with plastic headers since a child was killed when one burst over its bedroom. I'd seriously consider going unvented if you can source a cheap accumulator and pressure vessels, lots of upsides and few down, if any. Consider a simple zone system, like the standard S plan: a programmer and 2 honeywell zone valves. Have the DHW on one zone, space heating on other and run the DHW and pool in parallel, the DHW temperature set by a tank stat controlling its zone. When it is satisfied all the flow will go to pool. In winter you will need to arrange some sort of pump over compensation should the DHW and heating circuits become satisfied. As the programmer will not be controlling a burner you will be able to use the redundant contacts on the zone valves in series to cut the primary pump. I think you are bound to need a separate pump for the boiler to the accumulator.

I've managed to curb my desire for a working stirling engine at £150 but the various comments about stove fans have made me dangle a 12V 0.3A fan, ripped from a beer cooler, above the little Jotul. It's running off a wall wart and my wife says it is making a difference in this study. If I left it on 24/7 that would cost me about a fiver in electricity a year. The house is now cold for the first time this winter and I'm going to run out of logs. I'm guessing the large temperature differential (22C at ceiling level and 13.3C at floor) in the sitting room is indicative of poor insulation.

Like Difflock you need to take my advice with some circumspection, I'm not so hot on the wet side as I dealt mostly with feed and burner issues (because the plumbing didn't often cause a problem). When you say you lose water is that because the F&E tank overflows? My thinking would be a pumped circuit in the house, drawing from a plate heat exchanger, the primary of which would be pumped from the boiler circuit. This keeps both circuits separate and you could go unvented in the house. It would also allow the primary circuit to be at a higher temperature than the house circuit. Ball valves on the output of the boiler directing to either house circuit heat exchanger or swimming pool (but this may be an issue with DHW) on the grounds you will not need house heating and swimming pool heating. To avoid a heat exchanger for the pool could you weight plastic pipe in a loop to the bottom of the pool? NB most domestic pex pipe is not suitable for chlorinated pool water. I think a general rule for 28mm pipe is 70W/m per deg K so to sink 50kW ( probably the maximum heat you can pump through 28mm) with pool at <20 and water at 75C you'll need about 150m of pipe. Else you will need a second plate heat exchanger which can cope with pool water and keep the pool pump running whilst the boiler is running. I haven't got one out yet but used plate heat exchangers can be had from combi boilers. Coils have too small a surface area to transfer these large amounts of heat.

All seems sensible to me Bigger ones seem to be cheaper second hand and RHI may well put a lot on the market. Mine's too small on that rule, mind the boiler holds 600 litres so the total is around 2600 with 150kW on dry woodchip , as Huck says wet wood derates it considerably, once you get to 40%mc I cannot get the flue temperature above 120C nor have a clear exhaust. I am getting some interesting drying patterns in the hopper though which surprise me. Along the lines of the monorator gasifier. In the past I believed one could ignore drying in the hopper but now... I agree but in Huck's case the oil tank as an accumulator will not stand any pressure. He'll also need a fairly expensive pump for that volume and distance, prices start rocketing up once you get above a typical domestic15-50

Mother was pure dalmation and when he was acquired my daughter was told she'd run off with a springer! From looks and manner I feel he's got a good deal of english pointer. He's big though, 35kg. 60 quid buys you a dna test that lists the major and minor breeds present now. one day...

OK I assumed the expansion vessels were for both systems, I expect two 50l domestic ones were more available/cheaper than 100l. It doesn't matter how many expansion vessels you have, nor where they are in the system as long as the bladders are charged to the same pressure and they can cope with the 10% water volume expansion between cold and hot. Impressive, the old firm did something similar to a Buddhist monastery but that fired a gasifying cordwood boiler once per day. I worked well so I only made one familiarising visit and was never called out to it.

This one is just one year now, biggest pleasure of my weekend is walking with him. He's fast with a good nose. One mishap is when he ran through the woods opposite my house and returned to me with a puncture wound through the nearside front between the bone and tendon.

So you have 3 100 litre expansion vessels for the three DHW tanks and three in parallel for the space heating? Do you manually switch the solar heating? I worked on a sandler system in Brixton that used one 3000l tank for DHW and underfloor with super insulation and solar thermal input. The backup was 25kW pellet boiler. System was a disaster because it used a stratified tank with a diffusion tube, The heat wasn't metered so the 12 tenants controlled their temperature by opening windows. This meant the underfloor pump worked constantly and quickly ruined the stratification, the DHW plate heat exchanger pumps were cut out at 50C so no hot water. The design was also daft in that the solar thermal and boiler both fed into a common header, effectively the solar thermal circuit diluted the 75C water from the boiler. They should have switched solar heat to just pre warm boiler feed when there was no chance of solar reaching 50C in a day. Apart from discomfort there was a safety issue in that the housing association did not appoint a service contract, I was freelance snagger for the installation company which went bust, and went to fix minor problems when called by the housing association handyman. The solar system leaked and no one noticed and an automatic pump refilled the system. With no solar input the boiler ran 24/7 with a switch off every 6 hours to automatically de ash. Consequent to this with no chimney sweeping and a gas cowl terminating the flue, draught was lost because the cowl was blocked with soot. By this time the boiler internals had burned out in 4 years of constant use. This was all made worse by the housing association people being an uncaring bunch of jobsworths. Against my advice they replaced the boiler like for like instead of going for FIT under the RHI with a new bolier. I have only one circuit, a simple fan coil unit running straight off the accumulator. As it's running on arb arisings I have lots of feed problems so it generally only runs when I am at work. Yup I'd be interested in looking at the site. Woking BC crow about their renewables ( big CHP scheme and lots of PV but don't allow one to see what is being produced.

If that is centigrade then yes you are sending far too much heat up the flue. One reason may be too much air (probably secondary)

Second attempt at posting this : what about trying a couple of the load covers from an estate car, about 1.2m x 1.2 m and roll up. I used ones from an old astra estate.

Yes but he mentioned dhw tanks as separate volumes. I wondered if that was significant. I need to add a second expansion vessel as the new accumulator tank increases the volume such that I've had to reduce the temperature. That's my view as long as there is only iron and copper in the circuit, mind he says he spent £65k on his so an extra 600 quid for inhibitor is minor. I'm working on a fraction of that budget. I used a couple of 6m lengths of 2" barrel which my old boss came down, designed, cut and threaded just for the bends and connections. I think the black iron came to over 500 quid. I wouldn't want to try and tap threads on that by hand. Then 2 8m lengths of heat main into the barn where the accumulator sits. The small load I have on is run off 28mm ersatz hep20. I see I poked 1.5MWh into the system last week.

Any particular reason for 6 discrete expansion vessels?

Is it possible/practical to repair a punctured tank on an ms200t? The translucent side bit with the filler in it.

The corollary is that because it is not stable it's highly reactive and that is what makes it dangerous, I believe it inhibits the chemical that takes oxygen from blood and bungs it in the cells. Butterfly collectors used to use crushed laurel to kill their finds so I am always wary of being in an enclosed space with fresh laurel chip. I wouldn't worry about cyanide surviving a fire.

50mm heat main is about 60 quid/metre for the twin pipe, personally I would avoid it and pay more for a pair of singles if the delta T feed to return is high to better isolate any cross conduction. The end fittings are about £100 each though. It's just a 2" mdpe water pipe with closed cell insulation all round stuffed down a normal rigiduct. Many biomass systems will have thermal stores and this amounts to a lot of water in the system, often too much to dose with corrosion inhibitor. In a sealed system (still not allowed under building regs in domestic premises unless the latest part J changed that) it's not a big problem as any free oxygen dissolve in the water gets vented or reacts and then there is no more to do harm. In a vented system there is still a point where fresh air can get in at the F&E tank so these should have inhibitor. Antifreeze is another matter and apart from keeping the boiler running I don't know what would happen. I would hope the expansion vessel would cope with the main body freezing.

I saw at canford, one imported for ARBRE around the turn of the millenium, on a rottne base, it only managed about 80 500kg bales/day, has this improved?

I don't expect a battery electric one to compare well with a petroil one but what does 30 minutes run time (mentioned for the husky lion powered one)mean in practice, e.g. has anyone cut 5" discs until the battery of one of these runs out?

+1 and the spool block will be the bottleneck. You get more wear and tear as well as oil deterioration once the temperature gets above 40c (blood-heat).

Would this be a typical cost or a guess? Tracked chippers are fairly difficult to move without hydraulics being live unless you can get alongside and lift. So taking it off the trailer and away from lorry access should be more secure if the engine is well immobilised, and yes £700 is a small price to pay on a £28k machine, especially after having a 1928 nicked as well as a more expensive one. It is similar cost to the aftermarket tracker-immobiliser fitted which isn't without problems.