header tank circulating , from cold fill to vent

[dave b]

Hi
I am a first time user although i have read lots of post,s on here .

I have just fitted two , two port valves and a new pump to my system , which is an open vented system , we only moved in a short while ago and have had problems circulating the water to the 15 rad,s , ihad to turn the pump up full to get it moving , i will put sludge remover in over the next week or two blah blah blah .

the problem i have is this i fitted a new pump thinking that i may need a more powerfull one so i fitted a 6m head pump it was a 5m before .

the water is circulating from the f/e tank feed and back out of the vent with the force of a bath tap , the pump is set on n/o 1

is it that i have to increse the length of the vent pipe or what

by the way i have turned off the feed tap and it is running like a dream


please help Dave

 

[twgas]

Did you replace the two port valves or add them as an upgrade?
It shouldn't pump over on 1, possibly piped wrong or a restriction in the cold feed/open vent area.
The vent pipe should extend 450mm above the water level, I doubt if altering your's will have any great affect.
I assume the "feed tap" is on the cold feed, between the f&e tank and the system - "it shouldn't be there" - turning it off may remove the symptoms but it is not running like a dream. The pump is likely to dump water into the f&e tank and as it can't be replenished you will cause more problems.

 

[stanboy]

are you sure you have the pump in the correct direction

 

[dave b]

Did you replace the two port valves or add them as an upgrade?
It shouldn't pump over on 1, possibly piped wrong or a restriction in the cold feed/open vent area.
The vent pipe should extend 450mm above the water level, I doubt if altering your's will have any great affect.
I assume the "feed tap" is on the cold feed, between the f&e tank and the system - "it shouldn't be there" - turning it off may remove the symptoms but it is not running like a dream. The pump is likely to dump water into the f&e tank and as it can't be replenished you will cause more problems.

Thanks Mick

yes your right it,s not running like a dream

the valves were a replacement one was sticking closed and when i looked at the other it was a mess

the gate valve is on the cold feed , dont know why either the whole system works when i close the valve , and then run,s from the vent when i open it as it should be ,

do you not think that i should have put a 5m pump back on ? , do you think if i put the sludge remover in it may clear the partial blockage

 

[dave b]

are you sure you have the pump in the correct direction

Hi

Stanboy

Yes it is in the right direction thanks

my first thought was oh you pr--- , you have put the pump on
the wrong way, but no i managed to get that bit right

Dave

 

[twgas]

Before you add the cleanser, I would recommend cutting out the feed/vent connections and relacing with new tees and bit of pipe, probably best to use compression so that it can be disconnected easily in the future.
It should be configured; boiler->vent->feed->pump, with max 150mm between vent and feed.

 

[dave b]

Before you add the cleanser, I would recommend cutting out the feed/vent connections and relacing with new tees and bit of pipe, probably best to use compression so that it can be disconnected easily in the future.
It should be configured; boiler->vent->feed->pump, with max 150mm between vent and feed.

Yea , i thought that was the only option , but i turned off the feed from the tank , turned up the pump and banged the tee a good few times ,

now i have opened up the feed again , the pump is on 2 and i only have a trickle from the vent , about a half of a cup an hour ,

do you think now that i may get away with putting the vent poss a meter higher and then back down a meter ,

P/S the config is all ok

22mm from boiler up to vent , with a 22mm tee only 80mm across to another tee 22mm down to pump , and a 15mm feed from tank into that tee , the pump is about 300mm down from that tee.

Cheers for all your help
Dave

 

[twgas]

do you think now that i may get away with putting the vent poss a meter higher and then back down a meter ,

That is not the way to go, it will block up again, the cutting out is the only way.
How far above the pump is the f&e tank?

 

[DP]

I would also remove the valve on the feed pipe. Or at least disable it

 

[twgas]

I would also remove the valve on the feed pipe. Or at least disable it

good call

 

[dave b]

do you think now that i may get away with putting the vent poss a meter higher and then back down a meter ,

That is not the way to go, it will block up again, the cutting out is the only way.
How far above the pump is the f&e tank?

Thanks again Mick

I will do that

The tank is only about 1.5m above the pump , and about 2.0m away

ie the feed pipe go,s along the loft about 2m with a drop of about 150mm , then it go,s around a 90 degre bend a meter then drod,s down into the airing cupboard , the pump is about 1200 to 1300mm down from that.

Thanks Dave

 

[dave b]

I would also remove the valve on the feed pipe. Or at least disable it

Thanks D P

I do intend to remove this valve that there is no need for , but it is handy to have untill i sort the current problem ,

I will cut out the old pipe and rejoin using comp fitting,s in case the bas----- block,s up again.
At least it is giving me somthing to do at night and at weekend,s now the football season is over.
Dave

 

[twgas]

1·5m is ok, just, any less can cause the problems you have.

 

[dave b]

1·5m is ok, just, any less can cause the problems you have.

Well , what a weekend

I was going to cut out the " H " section on saturday . ie T to T , but as i was p----d off with it on thurs night banging away , i decided to go and
give it a taste of it,s own medicine , so i banged it a few time,s , and the system took it,s revenge.

I was leaning on the top pipe going into the coil on the cylinder which is a large tank 1500 x 450 mm , and it let me know by springing a leak on the joint , so saturday was taken up with fitting a new cylinder and cutting out the old pipework.
had a few bang,s , but put sludge remover in , and it,s started to ease up a bit , it was nice to have the heating blasting out over 30 degres inside while it was nearly that outside .

Thanks again for all your advice
Dave

 

[ChrisR]

See:
Pumping Over