oil boiler plus multi fuel stove boiler on one system

[paddyo]

I have an oil burner (grant 50/90) plus a multi fuel stove for my heating system. I normally fire up the oil boiler for about 2 hours and by then the stove is hot enough so i switch off oil boiler. At the minute the hot water circulates through the whole system,which means that even though the oil boiler is off, the hot water is being pumped or circulated through it. Could i fit some sort of valve so that the hot water doesn't have to go around the oil boiler? You see, my oil boiler is positioned in my detached garage,so the hot water has to travel all the way into my garage,then through my oil boiler and return.This doesnt seem very efficent to me. Any ideas?

 

[Best]

Do you know what method was used to connect the boilers together? A twin coil copper cylinder method is a common system for dual heating.
To be honest, - if it had been done by a proper engineer, neither boiler should heat the other, especially by pumping in!
It would really need an experienced guy to look at it first, but all I would say is a check valve (one way) valve normally could be fitted to the pumped pipes at oil boiler to stop fire pumping into oil boiler. But I would hesitate to say about the solid fuel stove as it should have open primary pipes as well as pumped pipes - but has it?

 

[lame plumber]

you need expert advice onsite, just adding valves is a no no .

 

[Best]

I agree^^^
A thorough check of the way it is piped is essential first. Many systems are done in strange unorthodox & even dangerous ways & putting a valve on a pipe might stop a boiler circulating or venting safely.
An oil boiler has a thermostat & safety stats, but a solid fuel fire can keep heating & in a worst case scenario could come under pressure, so is more dangerous.

 

[paddyo]

my system at the minute consists of oil boiler plus multi fuel stove (plus solar tubes which i wouldnt brag about) Im wondering is it possible to fit some sort of valve so that i can heat radiators only without heating my dhw cylinder? I do have a wee manual valve which if i shut off then it only heats the dhw cylinder,and if i turn on then it heats both dhw plus rads. But i have no way of heating the radiators only.

 

[SimonG]

In a word no, not without being done properly which will probably mean a lot of money.

 

[paddyo]

i do have a (triple) coil dhw cylinder. i also have solar tubes on roof

 

[paddyo]

replacing old grant 50/90

thinking of replacing my grant oil burner with one of those new more efficent grants. are they a lot easier on juice? my existing one is about 13 year old

 

[Best]

i do have a (triple) coil dhw cylinder. i also have solar tubes on roof

Need to find out if you have 4 pipes joined to stove. If you have, probably 2 will be large 28mm, which may be the primaries that heat the cylinder & should have a vent & feed pipe off them to a small expansion tank.
Other 2 pipes may be the pumped pipes for rads, which the oil boiler would be joined to. If all this is joined correctly & with thermostatic control on stove pump etc, then an engineer may be happy to use a check valve on the pumped pipes ONLY.
This raises the question why has this not been done by installer?

This is all speculation.

 

[lame plumber]

Re: replacing old grant 50/90

best you tell the world where you are and Im sure an oily on here would be happy to advice you at your premises. The new boilers are more efficient in the way they recover heat that would have previously gone up the chimney, as it still takes the same amount of fuel to provide 24 kw of heat output, its just less enregy is wasted now.

However, they may wish to review you current setup, having just looked at some of your previous posts.

 

[Best]

I assume the oil boiler also heats the solid fuel boiler (when the fire is not lit)?
That's also wrong.

 

[lame plumber]

Need to find out if you have 4 pipes joined to stove. If you have, probably 2 will be large 28mm, which may be the primaries that heat the cylinder & should have a vent & feed pipe off them to a small expansion tank.
Other 2 pipes may be the pumped pipes for rads, which the oil boiler would be joined to. If all this is joined correctly & with thermostatic control on stove pump etc, then an engineer may be happy to use a check valve on the pumped pipes ONLY.
This raises the question why has this not been done by installer?

This is all speculation.

have a look at padyo previous posts, you may build a picture

 

[Best]

Re: replacing old grant 50/90

Your Grant oil boiler, (Multipass or Euroflame) will be quite efficient , if it is serviced & set well.
It is probably at best about 85% max yearly. A condensing Grant claims to be approx 93% yearly.
So 8% minimum saving perhaps, but can be more.
It is the controls (motorised valves controlled by thermostats to cut circuits off) & TRVs
plus your house well insulated that saves you also!

 

[Dotty]

Moving to the oily forum.

 

[Dotty]

All threads by Paddyo merged.