Got Central heating working but no hot water please help a newbe

[keith lard]

Hi to all,
I have fitted a new rad in the upstairs bathroom, I had to drain the system which is Gravity fed, and alos fitted a new CH pump, I put water back into the system and working from downsatirs up bleed all rads,
I now have central heating BUT...
no hot water, I do have water coming out of the hot tap but it remains cold,
The back bolier (back of the fire downstairs) is a BAXI Burmuda 552 (about 25years old)
I can hear the water heating up but No hot water coming out the taps

Any Ideas what to do?

Also I have tried from the Kitchen running cold water back through the hot water tap to clear any 'air locks'


k.

 

[GrahamM]

Did you bleed air from the cylinder heating circuit? Look for a bleed valve at pipework going into your hot water cylinder.

 

[keith lard]

Hi Graham,
I have looked for this but just cannot find it!
The cylinder has two thick pipes coming down from the loft , one goes into the top, and the other goes to the bottom, which does have a drain cock. Also has 2 other pipes which I think feeds the cylinder.
Would the bleed vavle 'always' be close to the cylinder or are they sometimes else where in the pipe network?


k.

 

[keith lard]

 

[keith lard]

The first pic is the pipe at the bottom of the cylinder and the second is the one at the top, but cant see a blled valve.

 

[Bernie2]

Hmm!

Those pipes really have nothing to do with heating the water. One appears to be the vent pipe and the other the cold feed.
You should have if its a conventional system two other pipes going into the side of the cylinder known as, Primary pipes, Circulating pipes or Flow and Return. The flow being the top. But you don't seem to show any those pipes in your pictures.

The actual cylinder can be either direct, indirect or prismatic all of which work slightly different. Your bathroom rad could be on the main central heating circuit or the hot water heating supply circuit.

 

[keith lard]

Hi Bernie2,
From start to fininsh this is what happened.
Had a old rad in bathroom that never worked, turned water off, took old rad off and fitted new ones and new taps at both ends of the rad.
Fitted new CH pump, now there is a non-return valve which I did move the test point (nut in center of the valve), would this have an effect on anything?
Turned water back on and bleed all rads from downstairs working up stairs.

But now no hot water (just cold water comes out the hot water taps)
Rads up stairs are working, cold downstairs.

k.

 

[keith lard]

Also, my house was built around 1982
I do belive its a gravity fed system,
Baxi back bolier is at the back of the fire downstairs, the pump is upstairs.

k.

 

[Stu.roberts]

Try just heating the hw without the heating on, if this dosnt work you may need to file it, but i wouldn't recommend doing this unless you know what you are doing.

 

[keith lard]

Yes have tried that, I can hear the water bubbling then the Stat kicks in, have left it running for about an hour, but still no hot water???

k.

 

[Stu.roberts]

Then perhaps it's worth draining down and fitting a bleed vale on the flow pipe, as it just sound like an airlock to me

 

[keith lard]

Ok stu, thanks for your help.
Will try another drain

k.

 

[keith lard]

Well still no hot water...

have been looking here http://www.homebase.co.uk/wcsstore/homebase/assets/ht_understand_cenheating.pdf

I am sure my system is F2

But...

I must have a 3 way valve somewhere...

It is not near the pump, so out of your experiance where 'can' it be if not near the pump???


k.

 

[Stu.roberts]

Have you definatley not got gravity circs then?

 

[keith lard]

Yes, I have had a good look round the pump this aft, no sign of the 3 way valve.

Only place left to look is the loft, but is that a common place for a 3 way valve?


Did notice 3 power cables near the pump, 1 must be for the control switch on/off in the kitchen, the second must be for the Stat in the hall, the third 'maybe' is for the 3 way valve???

k.

 

[Stu.roberts]

Not sure about the wire pal, but your 3 port would come after the pump on the pipe, maybe this will help your search? Oh I just thought have you seen a wiring center for your heating?

 

[keith lard]

No wiring center 'just yet'
I am working on elimination, where the hell it is!

The pipe after the pump goes 'as far as I can see to a Rad in the same room, will attach a pic now of the pump.

k.

 

[keith lard]

The 2 long pipes above the pump normally are hot (but now cold), as these go to the cylinder in the airing cuboard, the pump direction is 'left' and as far as I can see left no valve, would this be on the joint with the rad it goes to?
I did have a look under the carpet for a access point , but could not see one.


k.

 

[Stu.roberts]

It looks like gravity hw pumped heating to me mate, you could pull the stat out the boiler and try to boil the air out of the circs, but I wouldn't try it unlessyou know what ur doing pal.

 

[keith lard]

yeah have read that regarding a Baxi 552 bolier, I know where the stat is on the bolier, may I ask, how long would you leave the stat out? how long on 'boil' ?

 

[Stu.roberts]

Hopefully 10 seconds cause once it's clear it's clear, u need to feel the pipes at the side of the cylinder if one of them is hot you know it's clear, just put hw on on it's own wait for the stat to kick in then pull it out it will make a bit of din then turn itoff put the stat back in and check the circs. DONT forget to put the stat back and don't leave itout to long

 

[Stu.roberts]

Just had a thought pal are giving your hw time to heat up?

 

[keith lard]

Yeah stu, I put the stat on to full on the bolier, and have left it an hour, still freezing water out the hot tap.

Will try the 'boil' trick today, thanks for letting me know 10 seconds of boil shoud be enough, someone on another forum said 10 minutes!!!

think it was a mis type ;-)

k.

 

[keith lard]

Well have 'finally' got it going, for those who have googled 'baxi 552'
here is what I did

Very simple, The drain cock on the Kitchen Rad (lowest point in the house) is what I used to drain the system, I used this in reverse, I attached I cold water hose pipe to it and reversed the drain, but do this when the central heating pump is running water does come out the outflow pipe (sticking outside the house)

but it did get rid of the air lock!

anyway all happy now, got CH working a treat and nice 'hot water' once again !!!

THANKS TO ALL WHO REPLIED TO MY THREAD!!! MORE WISER ON THE BAXI 552 GRAVITY SYSTEM!


K.