How to disable a back-boiler?

[Daniël Bos]

I know capping it off would be really stupid....

 

How do you know your boiler is still ok after running it disconnected for two years? Do you pressure test it regularly?

 

I run a couple of Rayburn cookers with back boilers disconnected but have no intention of using them in the future.

This hunter however has so much water-heating capacity that I don't want to risk ruining it as it may come in handy some time.

[pycoed]

By OK I mean it looks OK! No holes visible, that is.

I don't intend using the boiler again - I did have it connected to the coal central heating system, but when I moved the main boiler (Trianco) to a boilerhouse, I decided re-connecting it wasn't worth the hassle for the minuscule amount of hot water it delivered.

[treequip]

I know capping it off would be really stupid....

 

How do you know your boiler is still ok after running it disconnected for two years? Do you pressure test it regularly?

 

I run a couple of Rayburn cookers with back boilers disconnected but have no intention of using them in the future.

This hunter however has so much water-heating capacity that I don't want to risk ruining it as it may come in handy some time.

 

Its a bit of a moot point, your options are run it wet, run it dry, (without making a bomb:001_huh:) or don't run it.

[Pumpy]

Hey Dan, cross posted before. Yeah good mate, has Hannah recovered from that mental swim? nutter, top job

 

I thought you meant your old bamboo frame yurt The Hunter should be OK in that monster, the air controls are brilliant if the rope seals are good so you should be able to get it goldilocks If it were me I'd get a set of fire bricks and cut em to box around the boiler (wear a dust mask them bricks are made of orrible stuff) cut the baffle plate down with an angle grinder to accommodate the fire bricks... jib job

 

The installation distructions make such a fuss about putting a thermostat on the return so it's not cycling cold water when it's first lit, to avoid excessive boiler corrosion, I wouldn't run it dry without fire bricks protecting it.

Edited September 25, 2013 by Pumpy

[drythropple]

Hi guys,

 

I bought a second hand hunter herald 14 last week. I'd not seen it or any pictures and when I went to collect it I found it has a wraparound boiler.

 

I don't need the boiler right now and was wondering about the best way not to ruin it so I could plumb it in at a later date.

 

I thought about filling it with dry sand or vermiculite? It looks quite hard to remove and I'm on a very tight budget.

It's to go in a yurt so no worrying about building regs or stuff like that.

I ran mine with dry sand for 3 years, my friend "recycled" it , flushed out the sand with a power washer and now its heated his house for 2 years with no problem

[openspaceman]

I ran mine with dry sand for 3 years, my friend "recycled" it , flushed out the sand with a power washer and now its heated his house for 2 years with no problem

 

I've never done it but my guess is sand is better than vermiculite as it will conduct heat away from the metal better, once steel gets near red heat it doesn't last long.

[peatff]

I've never done it but my guess is sand is better than vermiculite as it will conduct heat away from the metal better, once steel gets near red heat it doesn't last long.

 

If your burner is getting the steel up to red heat inside the house you need to cut the air down, cherry red is about 900°. I'd try to isolate the boiler from the heat with soft firebrick as suggested by someone earlier.

[openspaceman]

If your burner is getting the steel up to red heat inside the house you need to cut the air down, cherry red is about 900°. I'd try to isolate the boiler from the heat with soft firebrick as suggested by someone earlier.

 

Firstly it's not my burner and secondly I'm not advocating it but it can happen, wood really needs hot conditions in the firebox to burn out, I typically measure 1100C in combustion chambers.

 

The walls seldom reach this because the heat has to conduct or radiate to the inside wall, through the metal and out to the ambient air. The rate at which it receives this heat and then passes it away will determine the equilibrium temperature of the wall. Put an insulator on the outside, like vermiculite, and the metal work gets hotter because it cannot get rid of heat through the insulator. A brick on the inside can work because it reduces heat getting to the wall but the wall still has to get rid of the heat coming through the brick or the brick just gets to the combustion heat as it cannot get rid of it through the wall.