Question on Stove with Back Boiler

MarkZ

Hi,

When back boilers are normally fitted, I believe that a new header tank is installed so that the boiler can vent into it and take cold water from it if overheats.

The reason normally given is that if electricity supply is lost, the pump will not function, and as the fire in the stove continues to burn, the water in the back boiler will get hotter and hotter until it boils. The header tank releases this pressure and allows colder water to feed into the stove to cool it down.

I come from the IT industry, and when we have a device that can't be allowed fail even if power is lost, we install an uninterruptable power supply onto the device. This is in effect a large battery that can keep the device running for a particular number of hours (calculatable) in the event of a power failure.

Could one of these be used to replace the header tank on a stove. In my case installing the header tank would be very expensive because of the way the pipes would need to be routed.

Good solution or bad solution?
Mark

M cebee

its a crazy idea:D

Hotblack Desiato

What if the pump fails :eek: ?

MarkZ

Good point on the pump failure issue. In my job if this was a valid concern, we would put in two devices. So, in this case it could be I suppose 2 pumps in order to cover off on the possibility of one of them failing.

All failsafe systems have there limits of course.

In the case of the header tank, the cold supply could fail, the ballcock could fail, the piping could become blocked etc.

Even with 1*UPS and 2*pumps, both pumps could suffer a bad fate at the same time since they are in the same location. Or, piping could become blocked.

There would be a safety valve on the system, so explosions due to pressure could never happen.

The installation of the header tank could cost 3-4K, so I am willing to do quite a bit of work in order to avoid it.

M cebee

Pump failure ,ups failure,wiring fault

Afaik the expansion is failsafe;)

even a backup power supply like a genny wouln't do

volvo 240

I can't believe anyone would charge 3-4k for a header tank to be installed!! Unless this if for installing a new system or heavily intergrating/modifying an existing system.
As an example. If I was to start my own buisiness. I would think I could supply and fit a solid fuel boiler heating system for around 4k. Villager AHI stove 1000 euros. 7 rads, copper pipework, liner etc 1,700 euros. labour 1,300 euros. I used to fit gas combination boilers including all labour and materials. Using copper pipe. 7 rads trv's uprate the gas pipework for 1,600 pounds 7 years ago!! On my own it took me a week!!
Are prices for plumbing materials much higher in Ireland than the UK, or are earnings heavily taxed so you have to charge more?

On my open vented woodburning boiler stove heating system I have:

3 bar safety valve near the stove on the flow.

Feed and vent pipes direct to the boiler from F&E tank. (4 tapping boiler)

pump.

Small expansion/header tank.

In the event of a powercut and the pump did not work I have 2 double gravity circulation radiators that would help to dissipate the heat from the stove.
All in as safe as it can be.
James:)