Gate Valve on HW Return

danjo

Have a Firebird Super 90 running on kerosene. There is a gate valve fitted on the return pipe from the coil in the HW tank. Below the valve the pipe joins the return from the rads, which goes to the boiler via the pump.
The question is ...what is the purpose of the gate valve fitted there?
It is fully open at the moment. Could it be used for balancing?

K.Flyer

danjo wrote: »

Have a Firebird Super 90 running on kerosene. There is a gate valve fitted on the return pipe from the coil in the HW tank. Below the valve the pipe joins the return from the rads, which goes to the boiler via the pump.
The question is ...what is the purpose of the gate valve fitted there?
It is fully open at the moment. Could it be used for balancing?

This valve is for balancing your central heating system and is normally only partially open, roughly one full turn out from closed. However systems vary and it may need to be adjusted further, (especially if you have your radiators on zone valves,) in order not to put too much back pressure on the circulating pump.

danjo

Thanks K.Flyer.
Rads are all in one zone but there is a motorized valve to select between HW or Heat + HW.

One more question..should pump be running when on HW or is only for Rads? Thanks for info.

danjo

K.Flyer

danjo wrote: »

Thanks K.Flyer.
Rads are all in one zone but there is a motorized valve to select between HW or Heat + HW.

One more question..should pump be running when on HW or is only for Rads? Thanks for info.

danjo

Once the boiler has been switched on the pump should be running on either setting HW or CH & HW.

danjo

Thanks again K.

danjo.

Sparkpea

unless the hot water is gravity fed then the pump wont be running

danjo

Sparkpea wrote: »

unless the hot water is gravity fed then the pump wont be running

Thanks for that, Just to clarify, if the HW is gravity fed then it does not need the pump?

K.Flyer

danjo wrote: »

Thanks for that, Just to clarify, if the HW is gravity fed then it does not need the pump?

If your central heating system has been installed correctly then your central heating circulating pump should be operating once your central heating boiler is switched on.

I'm not sure if Sparkpea is referring to a central heating pump, (possibly a water pressure booster pump?) but in your case with a firebird kerosene boiler your circulating pump should be on with the boiler.

danjo

That's very clear.
It is set up to come on with the boiler so all is well.

Thanks danjo

Sparkpea

Also just to clarify that the gatevalve is a balancing valve and imo if the pipework is 22mm or 28mm into the coil the gatevalve should be open halfway, if its 15mm then open full or it likely wont have one on 15mm. The more you cut it down the better chance the pump has of heating the radiators but if you turn it down too much then you run the risk of the heating expanding (pumping it into the header tank) but again this depends on what speed the pump is set to run at.. 1,2,3.