Soild Fuel Rayburn HTG

[lovejoy]

Hi guys fist post am hoping you may beable to help.
I am a fully qualified plumber and gas installer and have been working in the trade for the last 5 years on mainly new build property. I have never worked with solid fuel before. Now here is my problem:
I have been asked to look at a job where the guy wants to replace his current Rayburn, which just does cooking and HW, with one to run 4 or 5 rads upstairs. He currently has a Primatic cylinder running off this with HW only required downstairs. Now I know this will need replacing also as there is a largeish hole in the side currently patched with what looks like Denso and silicon!! The probem is he has already fitted the Htg flow and return pipework upstairs under the floors and laid new carpets and the airing cupboard is downstairs in a single storey extension. I am therefore thinking getting the header above the highest rad will be an issue, am I right in thinking this is correct as I think you cannot run unvented off solid fuel so vented will be required, therefore the header needs to be above he highest rad? I will struggle to get pipework to a tank in the main house roofspace now without ripping up new carpets. There is a small roofspace above the airing cupboard in which I can fit the header and it will be around level with the highest rad, will this be adequate? Also I will requite a cold storage tank, as the cold water is only required downstairs does it matter what hieght this is at? Finally I am not sure if any special accreditation is required to work on soild fuel?
Thanks for any help, will be very appreciated!! and sorry for lenghty post!!!
Cheers Dan.

 

[justlead1]

Hi. There are a few issues.
1.Rayburns will heat rads but a lot of fuel to get good results
2. Cylinder below rads, can under certain conditions heat the rads by gravitation, cooling the water. (issue in summer when immersion is used.)
3. If the F&R which has been installed has not been sized correctly circulation may be impaired.
5. If a pump is fitted, with the minimum head you suggest pumping over can be a problem.
6. Gravity circulation must be adequate to carry the heat generated by the Rayburn. To achieve this pipe sizing, circulating height, and general design to provide good circulation must be achieved.
7. The new carpet lifting are the least of your worries.
8. Over the years i have done these jobs for people who beat me into submission to carry out work. As they thought they had invented the wheel and would heat the house for nout. Wrong every time.
Good Luck

 

[tackleburger]

Surely it is not a problem when the immersion is used an immersion isn't going to heat rads.

I agree on the rest this is going to be a nightmare for you I fear. Watch the cold water you can put the whole house on mains no problem with that but you then have unequal hot & cold pressure so showers will be an issue unless they are electric.

 

[justlead1]

hi. On several occasions i have witnessed circulation from indirect cylinder when its position is raised but on ground floor and rads are on first floor. The cylinder coil can work in reverse. Heating the water inside the coil thus creating circulation to rads. This can be designed out, but one needs to be aware.

 

[lovejoy]

Thanks for your replies so far guys. There are no showers in the property so theres no problem there. The htg flow and return already in place are 22 to feed 4/5 rads. My main worry is getting the header abover the rads. Is it time to jump ship do you reckon? I haven't actually agreed to do the job or priced it yet and it sounds more trouble than its worth tbh, might just put in a massive price. Any more help would be appreciated mind...

 

[justlead1]

Hi. Have a go. 28 mm to cylinder, 22mm to rads as a minimum. Take the rads of the flow and return at boiler level. Monitor results when you fire up. It much more interesting than pumped systems. And your getting paid for it. It also Saturday and i had a drink. Good Luck

 

[Bungditin]

Always like to leave at least a meter above rad for expansion tank.