Connecting twin coil together! in indirect unvented cylinder

Thunderbird_2

Dear all

A new central heating is being installed at the moment, and we have a question regarding Twin Coil Indirect Unvented cylinder.

I need 250L minimum, and I want to install twin coil and connect them together to the boiler as big one coil (outlet of the top coil connected to the inlet of the bottom coil then back to the boiler)

The reason being, I have got 37kw boiler and would like to make most of it. The fast recovery coils are only rated 22kw. Can I use the solar coil in a boiler circulation? (obviously without solar panels) Or is it too thin to take the higher temperature and pressure from the boiler?

Many thanks

Thunderbird

HappyMJ

Thunderbird wrote: »

Dear all

A new central heating is being installed at the moment, and we have a question regarding Twin Coil Indirect Unvented cylinder.

I need 250L minimum, and I want to install twin coil and connect them together to the boiler as big one coil (outlet of the top coil connected to the inlet of the bottom coil then back to the boiler)

The reason being, I have got 37kw boiler and would like to make most of it. The fast recovery coils are only rated 22kw. Can I use the solar coil in a boiler circulation? (obviously without solar panels) Or is it too thin to take the higher temperature and pressure from the boiler?

Many thanks

Thunderbird

22kw will heat a tank of water of 250L in no time. I'd just leave it. The boiler will cycle on and off to use only 22kw of gas. It won't use 37kw for the entire heating period.

keystone

Your G3 ticketed installer will answer this question for you.

Cheers

Thunderbird_2

Thank you both for replying. My installer does not know if it is ok for the solar coil to be connected, he just says it will be ok on 22kw.

We have a bathroom and 2 shower rooms. I tend to use the shower a minimum of 20 minutes at a time and I don't want to run out of hot water.

So, can we connect both coils together? I would have bought a triple coil and connected the top two together (leaving the solar one abondoned for the future) but we don;t have the head clearance needed for a triple coil cylinder, hence the question whether or not a solar coil will take the higher temperature and pressure from the boiler circuit.

Any furthur advice will be gratefully received.

Many thanks

ziggyman99

Your under some misapprehension if you think that a solar system runs cooler and at less pressure than a heating system. A evacuated tube solar panel will reach stagnation temperatures of 270C - enough to melt solder. Normal working temperatures on my systems can be up to 130C at pressures of 1.5 bar. Way above the temp of a heating system and with comparable pressures.