Subject: V rocket rooman water heater Mon Oct 07, 2013 11:59 pm
This is my current project just working on a few ideas before I get to start welding it all up.
Few changes so far.. Internally Insulate both outside walls of firebox with refractory board. Insulate underneath stove with refractory board. Make door of 1"-2" square tube drill holes in tube side facing glass to provide air wash, couple of slots in outside of door with covers to control air input.
Still to figure out.... Placement of secondary air feed. Water jacket internal thickness...prob 2".
T2H Admin
Posts : 913 Join date : 2013-10-07
Subject: Re: V rocket rooman water heater Sat Oct 12, 2013 2:29 am
Have you been able to do a mock up on this yet?
ppotty1 Admin Admin
Posts : 241 Join date : 2013-09-30
Subject: Re: V rocket rooman water heater Sat Oct 12, 2013 6:05 am
Not yet, the lad who is getting the steel sheet for me only just dropped it off plus there are two pieces missing ! going to take the bits I have round to another mates house to get it in his bending maching. Hope to start on it next week and think Im leaving out the water jacket as I know that part will work anyway.
T2H Admin
Posts : 913 Join date : 2013-10-07
Subject: Re: V rocket rooman water heater Thu Oct 17, 2013 5:12 pm
What are your steel prices like for projects like you have worked on? It would be interesting to know.
T2H Admin
Posts : 913 Join date : 2013-10-07
Subject: Re: V rocket rooman water heater Thu Oct 17, 2013 5:14 pm
You may not have to use a pump, you may be able to use a thermal siphon.
ppotty1 Admin Admin
Posts : 241 Join date : 2013-09-30
Subject: Re: V rocket rooman water heater Sat Oct 19, 2013 4:37 am
The cost of steel here has gone crazy over the last few years so I cant tell you what this would cost, I get the steel from a friend who runs a small company that make signs etc. I ask him to keep the off cuts he has no use for and I pay him over the scrap price he would normally get. The cost for this project is around £20.00
Pekka Leskelä
Posts : 36 Join date : 2013-10-07 Age : 63 Location : Finland
Subject: Re: V rocket rooman water heater Wed Oct 23, 2013 7:11 pm
It probably needs a shortcut to the chimey for the lighting up. Should be easy to make a damper for that.
Check this interesting downdraft stove Twinfire http://www.wittus.com/ Door handle operates also the damper.
ppotty1 Admin Admin
Posts : 241 Join date : 2013-09-30
Subject: Re: V rocket rooman water heater Tue Oct 29, 2013 11:35 am
Updates..
Secondary air feed going in underneath the stove with air control. Water jacket will be 2 inch.
I did have second thoughts on building a mock up and was going to go straight for the final build version. However The final build will probably have to wait now so will crack on with the mock up version and get it all working....hopefully.
ppotty1 Admin Admin
Posts : 241 Join date : 2013-09-30
Subject: Re: V rocket rooman water heater Tue Oct 29, 2013 11:37 am
Pekka Leskelä wrote:
It probably needs a shortcut to the chimey for the lighting up. Should be easy to make a damper for that.
Check this interesting downdraft stove Twinfire http://www.wittus.com/ Door handle operates also the damper.
Wow nice stoves Pekka...nice prices too :o
ppotty1 Admin Admin
Posts : 241 Join date : 2013-09-30
Subject: Re: V rocket rooman water heater Mon Dec 02, 2013 12:24 pm
Latest vid and progress on this.
woodrascal
Posts : 26 Join date : 2013-11-29
Subject: Re: V rocket rooman water heater Tue Dec 03, 2013 11:27 pm
Looking very Good!
Any ideas as to how many btu's/hr your finished boiler will put out?
caotropheus Subscribers
Posts : 333 Join date : 2013-10-07
Subject: Re: V rocket rooman water heater Wed Dec 04, 2013 2:59 pm
Nice stove
My main concern goes for water temperatures being too high. Are you going to heat water is a closed or a open system?
ppotty1 Admin Admin
Posts : 241 Join date : 2013-09-30
Subject: Re: V rocket rooman water heater Fri Dec 06, 2013 4:27 am
Woodrascal....I have no idea what the output will be, I guess I could figure it out though.
Caotrop...Open system, water passes through a vented coil in the cylinder for hot water, and directly through the radiators all part of the same system. When pressure builds up usually through overheating a stat fires up a pump to push it round the rads. never managed to boil these yet ;)
woodrascal
Posts : 26 Join date : 2013-11-29
Subject: Re: V rocket rooman water heater Fri Dec 06, 2013 10:52 pm
ppotty1 Admin wrote:
Woodrascal....I have no idea what the output will be, I guess I could figure it out though.
Is there a formula you could pass on to work out the surface area/volume/material thickness/whatever, required to achieve a given number of btu's/hr output? It would be a great help to me for my own rocket boiler project.
Many thanks
ppotty1 Admin Admin
Posts : 241 Join date : 2013-09-30
Subject: Re: V rocket rooman water heater Sat Dec 07, 2013 9:01 am
woodrascal wrote:
ppotty1 Admin wrote:
Woodrascal....I have no idea what the output will be, I guess I could figure it out though.
Is there a formula you could pass on to work out the surface area/volume/material thickness/whatever, required to achieve a given number of btu's/hr output? It would be a great help to me for my own rocket boiler project.
Many thanks
Will have a word with a mate of mine who's a heating engineer, pretty sure he will be able to help out.
alan m
Posts : 14 Join date : 2013-12-04 Location : ireland
Subject: Re: V rocket rooman water heater Sun Dec 08, 2013 8:13 am
looking good. it should work great. i think i would add a second layer to the second door. have a sheet flush with the inside.. maybe wedge it there then leave a gap and put a second sheet outside that. the air gap should insulate it a bit and keep the heat in the boiler
i think i would change the back of the boiler a bit. you have the heat going down adn back up behind the boiler. i would worry that you will be heating the exaust gasses a bit. i would put a layer of insulation at the back of that plate. then continue the boiler up behind the insulation. then conect the return from the cylender to that hopefully the exaust gasses would be hotter than the return temps adn would then pre heat the water before it got to the intense heat of the main boiler.
i would also add some kind of heat sink to that area. this should increase the surface area and pull more heat out of the exaust gasses.
ppotty1 Admin Admin
Posts : 241 Join date : 2013-09-30
Subject: Re: V rocket rooman water heater Wed Dec 11, 2013 11:13 am
Thanks Alan, All of the heat on this so far is radiant I would guess the stove body will be cooler once the Jacket is filled, Id like to keep the temps fairly high in the flue and inside the body to reduce condensation, will know alot more once I fill the jacket and take more readings. Could end up changing alot more yet.
gadily Moderator
Posts : 1477 Join date : 2013-12-08
Subject: Re: V rocket rooman water heater Thu Dec 12, 2013 10:01 am
i like your design seen the vids
but to cancel the drip down of water inside the system use a preheat water system
preheat either at flue point or preheat externally to the main heat system your creating a box which holds heat use this heat as a preheat system
just one thing make sure parts can be swapable as this is plumbers gripes with any system they design it takes ages to swap old parts out and the amount of things that you need to take apart just to get to this part is the most annoying