Heating System Help

azzeretti

I have had lots of problems with my heating system. I have managed to figure out the following and I am hoping someone can help?

The system is an Oil fueled system.

Most of the radiators do not heat more than 2 inches from the top. Two, very small raditors, heat fully. I got a plumber in and he closed off a valve entering the hotwater tank, and suddenly all the radiators heat. He told me to turn try opennig the valvue slightly and get the right balance to heat the two. The problem is that even a very slight opening of this vlave stops the radiators heating. Closing the valve is fine and the rads work, but we can't heat the water without using the immersion.

Can anybody suggest anything to try?

Lex Luthor

maybe the valve entering teh hot water tank is faulty and cannot regulate properly. By slightly opening it, it opens fully. You should be able to grade the openings and it sounds like the tank is taking all the hot water.

You might also try to balance the rads aswell

http://www.diydata.com/projects/centralheating/balancing/balancing.htm

Have a look at this

if you don't have a thermocouple to measure the temps on the rads...general rule of thumb is and this is only general.

Rad furthest from boiler is open fully, next rad before that is closed slightly, and so on to the first rad nearest the boiler which is only open slightly. Try to work it out so you open them equally as much the futher you move away from the boiler.

Also, bleed the rads.

ircoha

azzeretti wrote:

I have had lots of problems with my heating system. I have managed to figure out the following and I am hoping someone can help?

The system is an Oil fueled system.

Most of the radiators do not heat more than 2 inches from the top. Two, very small raditors, heat fully. I got a plumber in and he closed off a valve entering the hotwater tank, and suddenly all the radiators heat. He told me to turn try opennig the valvue slightly and get the right balance to heat the two. The problem is that even a very slight opening of this vlave stops the radiators heating. Closing the valve is fine and the rads work, but we can't heat the water without using the immersion.

Can anybody suggest anything to try?

It seems to me that the resistance through the HW cylinder is less than the resistence through the rad circuit, hence the problem u have.

If you can have your plumber replace the aforementioned valve with an electric 2 port motorised zone valve, http://www.myson.ie/pages/motorisedvalves.htm
u can then get a 2 zone time clock and heat the water first and then have the heating on.

if balancing as per Lex above it is the lockshiled valves u adjust, with the normal valve fully open

JamesM

azzeretti wrote:

I have had lots of problems with my heating system. I have managed to figure out the following and I am hoping someone can help?

The system is an Oil fueled system.

Most of the radiators do not heat more than 2 inches from the top. Two, very small raditors, heat fully. I got a plumber in and he closed off a valve entering the hotwater tank, and suddenly all the radiators heat. He told me to turn try opennig the valvue slightly and get the right balance to heat the two. The problem is that even a very slight opening of this vlave stops the radiators heating. Closing the valve is fine and the rads work, but we can't heat the water without using the immersion.

Can anybody suggest anything to try?

The first questions have to be: How old is the system and did it ever work. If it used to work OK, something has gone wrong. There is certainly a circulation problem. If it is an old system, maybe there is corrosion or sludge in the pipes to the rads, and they are partially blocked. Does the water pump have more than one speed ? Is it set to the fastest speed. If the system used to work OK, There is no point in fitting new motorised valves or anthing else until you find the problem with the existing system.
Jim.
P.S. Have you changed the system in any way recently - Were the 2 small rads, which are heating, fitted after the rest of the system ?