Hi,

I replaced the circulator pump in my system and I now have no pressure from the boiler!

I shut off the valves either side of the pump before replacing.

I took the pump out and opened the valve from the boiler ( I confirmed it was opening by putting a screwdriver up the pipe!) but nothing came through. There is no header tank in the loft, the water feed pipe disapears off down through the floor boards and I can't trace it.

The boiler is a potterton PrimaB.

Questions:
1. I don't understand where the feed is coming from, does anyone know anything about this type of boiler, can't seem to find any info on the net. I assume it is a sealed system?

2. There are two pipes that go straight up from the boiler and stop at a little pot thing with what looks like a car tyre valve dust cap on the top, not sure what they are



cheers for any help

Robert

"bobonacus" wrote in message
...

Hi,

I replaced the circulator pump in my system and I now have no pressure
from the boiler!

I shut off the valves either side of the pump before replacing.

I took the pump out and opened the valve from the boiler ( I confirmed
it was opening by putting a screwdriver up the pipe!) but nothing came
through. There is no header tank in the loft, the water feed pipe
disapears off down through the floor boards and I can't trace it.

The boiler is a potterton PrimaB.

Questions:
1. I don't understand where the feed is coming from, does anyone know
anything about this type of boiler, can't seem to find any info on the
net. I assume it is a sealed system?

2. There are two pipes that go straight up from the boiler and stop at
a little pot thing with what looks like a car tyre valve dust cap on
the top, not sure what they are

[image: http://www.rob-k.co.uk/boiler.jpg]

cheers for any help

Robert


--
bobonacus

The little pot with the Schraeder valve thingy is the air separator: I
believe the knurled cap should be unscrewed a turn or two to allow air
venting.

I'm not too sure what your other problem is. Are you saying your pressure
guage is reading zero? If so ( i.e. you have a sealed pressurised system ),
then you need to get some water into the loop. This is usually achieved with
a 'filling loop'. Depending on your boiler, this may be a braided pipe with
a valve at either end goig from your mains cold water feed pipe to the CH
flow ( or return ) pipe. Alternatively, it could have been remved ( it is
supposed to be to stop leaks into the mains water system, so you'll need to
fid one and connect it up, or perhaps you will have a built in filling loop
in some discreet position beneath your boiler, and there will be a couple of
'tiny valves that need opening with specail keys ( a bit like raiator
keys ). Bottom line is, you need to open two valves to allow mains water
into your CH loop to pressurise it ( and then close them again ).

Andy.

the things above your boiler are auto air vents , make sure the caps are not screwed down tight , or the air wont get out ,

from looking at your picture I would say you have a system boiler not a combi ,
therefore there must be a cold feed to the system somewhere , probably in the airing cupboard , unless its a very new system , it will probably be a 15mm pipe , you could trace it from the heat/expansion tank in the roof space , you should have two tanks , a big one and a little one , its the little one ,
check the tank hasn't emptied with the arm from the ball valve stuck in the up position , if it has , easy fix , free the arm .
if the tank is full , you may have a blocked cold feed , very common , this will mean cutting the cold feed where it joins the system , unblocking the pipe , and re-joining the pipe , there will be some water , so be carefull , a rad valve changing kit is usefull for doing this , if your very lucky someone may have put a valve in just above where the cold feed joins the system , if not , put one in when you cut the pipe .
this is just a guess , as i cant tell for sure without being there , but the way to tell if your cold feed is blocked , is to put a drain on the system , and see if the h/e tank starts topping itself up , if it does the cold feed is ok ,
hope this helps .

"andrewpreece" wrote in message
...

"bobonacus" wrote in message
...

Hi,

I replaced the circulator pump in my system and I now have no pressure
from the boiler!

I shut off the valves either side of the pump before replacing.

I took the pump out and opened the valve from the boiler ( I confirmed
it was opening by putting a screwdriver up the pipe!) but nothing came
through. There is no header tank in the loft, the water feed pipe
disapears off down through the floor boards and I can't trace it.

The boiler is a potterton PrimaB.

Questions:
1. I don't understand where the feed is coming from, does anyone know
anything about this type of boiler, can't seem to find any info on the
net. I assume it is a sealed system?

2. There are two pipes that go straight up from the boiler and stop at
a little pot thing with what looks like a car tyre valve dust cap on
the top, not sure what they are

[image: http://www.rob-k.co.uk/boiler.jpg]

cheers for any help

Robert


--
bobonacus

The little pot with the Schraeder valve thingy is the air separator: I
believe the knurled cap should be unscrewed a turn or two to allow air
venting.

They are automatic air vents.

I'm not too sure what your other problem is. Are you saying your pressure
guage is reading zero? If so ( i.e. you have a sealed pressurised
system ),
then you need to get some water into the loop. This is usually achieved
with
a 'filling loop'. Depending on your boiler, this may be a braided pipe
with
a valve at either end goig from your mains cold water feed pipe to the CH
flow ( or return ) pipe. Alternatively, it could have been remved ( it is
supposed to be to stop leaks into the mains water system, so you'll need
to
fid one and connect it up, or perhaps you will have a built in filling
loop
in some discreet position beneath your boiler, and there will be a couple
of
'tiny valves that need opening with specail keys ( a bit like raiator
keys ). Bottom line is, you need to open two valves to allow mains water
into your CH loop to pressurise it ( and then close them again ).

Andy.

"Tony" wrote in message
...

the things above your boiler are auto air vents , make sure the caps are
not screwed down tight , or the air wont get out ,

Auto air vents are for filling/commissioning purposes only. Once the system
is free of air the tops are to be screwed down. Combi instructions
actually state this a smost have integrated. When the auto air vent is open
hydrogen from internal corrosion may escape. If there is hydrogen in the
sytem it will make the tops of rads cold, and that is a sign that the system
requires proper attention not just releasing it and refilling.

thats all very well and good , but that isn't a combi boiler .

"Tony" wrote in message
...

IMM Wrote:
"Tony" wrote in message
...-

the things above your boiler are auto air vents , make sure the caps
are
not screwed down tight , or the air wont get out ,-

Auto air vents are for filling/commissioning purposes only. Once the
system
is free of air the tops are to be screwed down. Combi instructions
actually state this a smost have integrated. When the auto air vent is
open
hydrogen from internal corrosion may escape. If there is hydrogen in
the
sytem it will make the tops of rads cold, and that is a sign that the
system
requires proper attention not just releasing it and refilling.

thats all very well and good , but that isn't a combi boiler .

I know that and I never said it was. I gave the e,g., of combi
instructions. It is clear this boiler did not come with auto air vents.