Advice pls - convert from back boiler to oil fired centeral heating system

clearlyn

Hi All

I am a fairly handy DIY person(i think). I have recently had some house renovations done and i have put in some additional radiator piping and radiators(3No). My existing heating consists of 7 radiators driven by a fire place back boiler radiator system.

I would now like to install a oil fired burner and connect in to my existing radiators along with my new radiators loop(4No.). Of course i have had quotes from plumbers to do supply the burner and do the cutoffs/hook ups but they all wanted in excess of €3000 for what I estimate is probally about 6-8 hours work!

Can anybody offer any advice please or give me some pointers.


Thanks

JamesM

For a start, Have you decided where you want to place the oil fired boiler ? In the kitchen, utility room, outside shed, garage attached to the house, or cabinpac (it's own little box outside)
Jim

clearlyn

Jim

Thanks for the reply. The oil fired boiler will be an internal sealed type and housed in a exterior utility room(2m from the house)(quoted €1100 at Heatmerchants). All the new piping is terminated at that point. The location is approx 4-6m from the water cylinder,back boiler and rest of piping(it a small house).

I am in the electrical field and from my view point it should not be too differcult to convert. The existing back boiler heating system has its own top up tank in the ceiling. Also the back boiler 1 inch pipes appear to go through the cylinder on route to the radiators. To keep it simple I think that I just need to break into the existing pipe feed with the oil fired boiler new hot water feed and presumbaly break in the return radiator pipe to the burner??

Any help is greatly appreciated

rooferPete

Hi,

I think you will find there is a bit more to linking a gravity system and a pressurised system (proposed).

There is also the question of non return valves, pump, thermostats, oil tank and pipe work etc.

My reading of your post is you expect to tee into the existing flow and return pipes just before they join the coil in the the existing cylinder ?

There is a bit more involved than just joining the pipes together, as much as I know with three systems in my house I would still bring my plumber in to do a link up like you are proposing.

The price based on your description does not look to be over the top in todays market.

.

JamesM

Pete is correct - I was mistakenly assuming that you were getting rid of the back boiler and I was trying to build up a picture of where you were going to run pipes etc. If you are retaining the backboiler, then, as Pete says, there is indeed a lot more work involved. Also you will need sombody competent to design the layout.
Jim.

ismynametoolong

Clearlyn . I had a back boiler system and installed an oil fired burner but i bypassed the back boiler and used the original attic tank supply and most of the piping joining up the piping from the new boiler where the original pump was installed with a new pump at the new boiler .The pressure relief valves can be installed near the boiler and we used the original expansion pipe into attic heater tank .It was at least 8 years ago and with new regulations i would make sure any work you undertake is done so in accordance with the regs ( Visit your Library ) a great source of info . I only last month blocked up the chimney that had the back boiler and dumped same , I also fitted a manual zone valve to isolate the heat upstairs and the difference is unbelieveable , all downstairs rads can be at full heat within 5 - 7 mins ideal if just arriving into the house on a cold day .

clearlyn

Thanks to rooferpete,jamesm and ismynametoolong for you replys.

It look like it will be much easier to blank off/bypass the back boiler. As ismy.... says I could then use the original attic tank supply and most of the existing piping joining up the original pump and original rads. The pressure relief valves can be installed near the boiler and i could use the original expansion pipe in the attic top up tank.

Please see the attachment a typical system taken from the web. I believe that my existing back boiler preforms the same position and function as the central heating boiler in the attachment. In theory I simply need to cap off the back boiler and tie in the new feed and return pipe from my new central heating boiler in their place. Am i on the right track, will I be one step closer to replacing the turf with a switch????

rooferPete

Hi,

Most sealed oil boilers that I know of use a pressurised system, they don't need a tank in the attic and are topped up when being serviced or vented, the big difference is the pressurised system is more effecient.

You can link the oil boiler to your back boiler and if like me you like to see the flames then the fire should be giving at least background heat.

What you want to avoid is your oil boiler heating your back boiler because that will cost you about three good sized radiators.

If you decide to eliminate the back boiler don't cap it off or it could explode leave the pipe fittings open by cutting them back and blanking the flow and return pipes, when you have emptied the boiler to below the return connection use a wet and dry vacum cleaner to remove the last of the water, to be safe you can drill a few holes in the boiler.

Personally I would keep the boiler working as long as possible by using a gravity system for the oil boiler, the difference in cost will not be that much but the comfort of having the alternative even as a back up could be worth it.

.

JamesM

clearlyn wrote:

Am i on the right track, will I be one step closer to replacing the turf with a switch????

Getting closer ! BUT, because of the danger of a backboiler overheating, the circuit from the backboiler to the cylinder and on up to the header tank in the attic, is the primary curcuit, with the circuit to the rads branching off that. The existing water pump is on the rads circuit.
When you fit the oil boiler in the utility room, you will need a water pump on the return out there. If the larger bore pipe is going up to the cylinder and back to the oil boiler, then the hot water will travel round this circuit and not flow too well through the branch to the rads. You could install a valve in the flow before it enters the cylinder. This could be partially closed to to cut down the flow to the cylinder and redirect it to the rads.
It is difficult to come up with ideas without actually seeing the layout.
In the utility room - presumably you will be burning kerosene and have the boiler close to an outside wall. If possible, keep the pipes over ground, well lagged, all the way to the house. Try to run them along a boundry wall if possible. Only go underground if you have to and for as short a length as possible. Can't think of anything else, as I said, it is difficult without seeing the layout.
Jim.

clearlyn

Guys

Thanks for all the advice. Its safe to say that I am now uncertain of my ability to do this job properly. :eek:

I am a bit confused as to wheather I should continue to use the open vent or presurised sytem. Also there seems to be many arguments for eliminating or retaining the back boiler. If any body can still offer any direction I would be greatful.
Also the original guy that I got the quote from is gone to work in the UK, if anybody can recommend a person that can cover the greystones area that can give a quote for the work I would be most greatful. I am not sure if this will break the forums advertising rules,if that is the case perhaps its better to use private messaging.

Regards
clearlyn

mrbig

I asume the back boiler you are refering to is in an open fire, if so you are beter off without it, they are horibly ineffecient. You will save yourself alot of cost in the longrun by geting a good plumber on the job, 3000 sounds a bit steep was that including materials?

Reyman

Nice to hear good old Roofer Pete's wise words from back in 2005 !
Where is this man now anyone know?