Several things wrong with new flat - no central heating, low hot water pressure even with water pump, noisey pump

[kiich]

Morning all.

First, thanks for all your help and advise so far - most useful. I was up till 2am looking at the boiler, pipes etc just to work out how the heck all this work!

anyways, here are the answers i promised to give - i still haven't got CH yet but i havent done anything to the valve yet as i only switched the whole thing off this morning - so i'm hoping when i get back today, everything will be cooled down etc which is what i read to do before any work??

kiichi>> this turned out to be 3

from the valve:

1 pipe connected to another pipe which connects to the water pump, boiler and cylinder 1 pipe connected to the cylinder directly (labled hot water port B) 1 pipe going down to the floor labled central heating port A

the valve is SUNVIC SD 1752 and has a label titled UNISHARE. how do i know that this is 2 or 3 port valve though?

i haven't opened up the plastic case yet - because i was scared it might cause damage or water might come out - should i worry about these things?

to the cylinder , there are 4 pipes - can someone tell me what each might be doing??

1 pipe from the ceiling to the top of cylinder 1 pipe from the ceiling to the bottom of the cylinder 1 pipe from valve 1 pipe from boiler

the cylinder says it is a indirect cylinder

cylinder - it would also have to have wires >connecting to it).

kiichi>>

the 7 day immersion heater timer was indeed connected to the top of cylinder - so i think i can say that this is for the backup only right? and can have it set to "PERMANENTLY OFF" setting??

things i noticed:

the pipe coming out of the valve out of the "hot water" port is HOT the pipe coming out of the valve out of the "central heating" port is warm/cold as it gets to the floor

That kind of indicates to me that there is no hot water going towards the radiators, right? Or does the pipes for CH not get that hot??

as i said i havent opened up the valve (the white plastic on the valve) because i was too scared to do it myself and cause damage :) but i can do it myself right without getting a plumber in?

all power to the valve, boiler and everything else in the airing cupboard is OFF before i do this.

thanks Kiichi

[kiich]

hi again

just to add to my post above, the Valve does not seem to have any lever,switch or any thing that resembles something that i can manually "turn" from outside - does that mean i need to open up the plastic white casing and would i find a lever inside then? kiichi

[kiich]

hi again

here's a ASCI diagram of the "cables" in the airing cupboard i will do one for pipes as well later the only power supply cable i can see is:

one from fuse to boiler timer one from fuse to another power socket for shower pump

how does the boiler get power electrical wise? or does it at all?? via the cable from boiler timer?

-------------------------------- | | fuse 7 day-immersion-timer powersocket -- -- -- | | | | | |---[shower pump] -- -- -- | | | --------------------------- | | | -------------- | -----| boiler timer |---[pump] | ---| |---[valve] | | -------------- | | | | ----cylinder---- | | | | | | [boiler] ---------------------|-[thermostat] | | | | | ---------------- | something i cant figure out | round object | --- -- | |---[into wall] ---

whats the round object that i cant figure out??? cant be power as thats coming from the main power socket withte fuse right?

i haven't opened the round object yet - could it be the line from the room thermostat??

hope the diagram comes out ok! thanks Kiichi

[kiich]

well that didnt work at all :(

how can i insert a diagram in google groups? cant do image as im on a unix box without any image app!

kiichi

[Owain]

It worked for me :-)

Can't do images anyway as they're prohibited on uk.* newsgroups and many newsservers will delete them (or delete the posting containing them) automatically.

Will leave the heating explanations to others :-)

Owain

[Dave Liquorice]

Looked fine to me. If viewing in google via the web it probably uses a proptional font which fups up ASCII art.

Via the timer it will control the boiler, pump and valve. Though the valve and stats well have their say as well of course...

Deescribe it a bit better. Like you say it might be connection to the room stat.

[Dave Plowman (News)]

It came out fine here. You just need to use the correct font to view it.

[Dave Plowman (News)]

Likely.

With the system all switched on - ie heating and hot water - turning down the cylinder stat (you should hear it click) while the room one is higher than ambient temp should force the motorised valve to the heating position, and you should hear this happening.

They're normally wired for hot water priority, so if both stats are calling for heat, the water one wins.

[kiich]

Dave - thanks for the reply.

cylinder stat (you should hear it click) while the >room one is higher

and you should hear this happening.

ok - here is my steps:

1) set the boiler program to be for both HW and CH 2) boiler comes on 3) turn down the thermostat on the cylinder - i hear that "click" 4) boiler turns OFF

Room one - you mean any room in the flat? well all the room are pretty cold (since no CH is coming on!)

after step 4), then thats it for me - nothing else seems to happen.

why would having room one higher than ambient temp 'force' the motorised valve to the heating position?

wouldnt that happen when the room temp is lower than my room thermostat settings? i.e. LOWER than ambient temp?

'They' as in the valve right?

so can i unscrew the screws on the valve and take off the cream plastic casing to look inside without killing myself?

So if the hot water works, this means (please confirm someone)

a) Water pump is working b) Valve is working for hot water

correct? Should the water pump and the valve making some noise/vibration when everything is working? its hard to tell from mine

- when boiler comes on, the pump does seem to be vibrating and so does the valve - but its so little vibration, i'm not sure if it is the boiler's vibration filtering on to them (since they are so close to each other) ?

thanks Kiichi

[Dave Plowman (News)]

Ah. I was assuming somewhere in the flat there is a thermostat that sets the overall temp, and TRVs in the rooms trim that. Commonly in the hallway. Or have *all* rads got TRVs?

Only if you have a room stat somewhere - which is what your wiring diagram suggests.

[kiich]

hi

here's the PIPE diagram as promised

to from to top of to bottom of pump ceiling cylinder cylinder

1| 2| 3| 4| 5| | | | | | | - - | | | | | connect| | | -----------------[| | | | | | | | | | | | | | ------- | | ********** | | shower|| | * cylinder *| | pump || | * *| ------- | | * *| | | | | -----* *| | | | | | ********** | | | | | | | | | | | | | | | --- | | | | | ---------------[to wall] | | | | | | | | | | | | | ------------- | | | | | | | | | | | | [joint]----- | | | | | | | | | | | | | | [boiler] [pump] | | | | | | | | | | | | | | | | | | | | | | | |--[valve] | | | | ------ | | | | | | | | | | | | | @ | | | | | | | | | | [ --- FLOOR --- ]

hope that comes ok and makes sense to someone! :)

thanks Kiichi

[kiich]

hi

here's the PIPE diagram as promised

to from to top of to bottom of [to wall] pump ceiling cylinder cylinder ----------

1| 2| 3| 4| 5| | | | | | | ------[joint] | - - | | | | | | | connect| | | ******** | -----------------[| | | * boiler * | | | | | | @ [pump] * * | | | | | | | | * * ------- | | ********** | | | ******** | shower|| | * cylinder *------[valve]--| | | pump || | * * | | | | ------- | | * * | | | | | | | | * *-- | | | | | | | ********** | | | | | | | | | | | | | | | ---------------------------- | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ --- FLOOR --- ]

hope that comes ok and makes sense to someone! :)

thanks Kiichi

[kiich]

Dave

overall temp, and TRVs in the >rooms trim that. Commonly in the hallway.

There is 1 thermostat near the living room. apart from that, i cant find any in the flat.

But there is a thermostat on the cylinder and i was told there should be another thermostat for the immersion heater at the top of the cylinder - but i have not had a look at this one yet.

No TRVs on any of my radiators.

ok - i do have a room stat. so if 1 room is hotter than the others, the motorised valve should cause the hot water to go down the 'central heating' pipe??

thanks kiichi

[Doctor Evil]

Please do take any notice of this man when it comes to heating. In another he advocates not servicing boilers for 18 years. He is dangerous.

[John Rumm]

Looks a bit like?:

could not find the exact model number of yours on the site, and hence can't tell if yours is a mid position valve or just a diverter. The current one seems to be mid position.

Count the pipes! - From your description yours is a 3 port. It has one pipe in and two out. (A 2 port valve is just like a motorised tap - it can be on or off. The three port can not shut off the flow of water, only change its path).

No - they are in two parts. The brass bit at the bottom is the wet part. It will usually have a small spindle that sticks out of it to control the position of the tap elements inside it. The box sat on top contains a motor and some control electronics. The motor turns the tap.

It is not uncommon for motors to fail, or for the taps to seize. You can usually remove the motor completely and see if you can turn the tap spindle manually (perhaps with a pair of pliers - it should not take much force to turn). You may find that if it is seized, it may only be temporarily - manually turning it may fix the problem.

HW out to the taps in the house...

Cold water into the cylinder from a cold water cistern in the loft...

Hot water from boiler in (via 3 port valve)...

Return pipe to boiler

As we suspected then ;-)

the cylinder - it would also have to have wires >connecting to it).

So there is no connection between the CH programmer and the time switch like you thought the other day then?

If so, good - that makes it simple. It looks like this is an ordinary immersion heater which you can ignore unless your boiler dies of you feel guilty about having such small electricity bills ;-)

Yup, spot on.

Nope, it should get as hot as the pipe going into the valve (or the one going currently to the cylinder)

Yup, you can do it yourself.

Yup - it is usually all fed from the boiler. So if you turn that off at the wall the rest will be off as well. Note that this does not apply to the immersion heater which will typically be independent.

[John Rumm]

Does it have a thumbwheel?

[John Rumm]

All from the timer by the looks of it. Som boilers control the pump and interface with the stats themselves, yours looks like everything is being done by the programmer with a single control to tell the boiler when to do its stuff.

Junction box?

i haven't opened the round object yet - could it be the line from the

Pretty likely...

ok here...

[kiich]

Not that i can see. i think it must be pretty old? because i couldnt see any manual lever/switch etc, i thought i'm not meant to open it

[John Rumm]

cylinder stat (you should hear it click) while the >room one is higher

and you should hear this happening.

Ah, that sounds to me like the system is not seeing a demand from the room stat. It may be it is not working correctly, or there is a wiring fault, or a fault with the programmer, or the programmers settings are wrong.

I think he meant "room one" as in *the* room thermostat (as opposed to the cylinder one)...

If it were a fault with the valve, you would expect the boiler to keep running, but the hot water from the boiler to still get directed to the HW, rather than being switched to the rads.

Your room thermostat is a simple device. It either "calls for heat" or it doesn't. When the room is colder than the setting on the front of the stat it will call for heat. When the room gets warmer than the setting on the stat it will stop calling. The idea being that it cycles the boiler on and off to keep the room temperature at about the setting on the stat.

Yes that is what Dave was saying.... just a bit of confusion over room one ;-)

Yup...

If you have a mid position valve, then in response to a demand from water and heating then it will sit in the mid position - hot water from the boiler ought to then flow to both rads and cylinder. If it is a diversion type, then the hot water will probably take priority should both call at once.

Without it killing you, yes ;-)

(what you do to yourself is your own business!)

Yes...

Sort of... if the valve were not working (i.e. failing to switch) it would still be working for hot water!)

It sounds more like the problem is with demand from the rooms stat though.

What type of stat is it?

Clunky manual:

something a bit more digital?

Chances are if it is a manual one then you should hear a click as you rotate the knob from one end of travel to the other. (the click will occur at around the point of rotation corresponding to the current room temperature).

Do you have a multimeter?

If not, go buy one (a simple five quid one from Maplin will do).

With the power off, have a peek at the wiring inside the room stat and report back. We will tell you where to stick the probes to diagnose what is going on with the stat ;-)

(the plan here is to prove that the room stat is working, and then trace back through the system til you find the bit which is not)

Nothing wrong with that! Pumps are designed to run quietly with as little vibration as possible - most folks would rather listen to the telly than have to listen to their central heating.

The valve will only make a sound (if at all) when moving from one position to the other.

[kiich]

yeah kind of! i saw that as well - but mine must be an older model as i do not have the red switch like the on on the web.

So i have to manually open it right?

thanks ;-) i wasnt sure because i have never seen a 2 port valve - but should have guessed mine is 3 port! thanks.

ok - so lets say i take off the cover from the box on top of the brass

- i should be expecting:

a) somekind of know or wheel that indicates what the valve is set b) these settings are: CH, HW and CH/HW - correct? or is CH,HW and auto? c) i should be able to turn the know/wheel to CH only and test if i get CH

and lets say i can take off the motor completely (you mean the box sitting on the brass right?) and i turn it manually and place it back on and start again - if i still have no CH, i call a plumber to replace the valve right?

thanks for the explanation on the pipes into the cylinder as well"

kiichi - when you say CH programmer, you mean the "7 day immersion heater timer" ?

And "time switch" as in the boiler programmer? sorry to ask a daft one here...

i had a look last night and i can only see 1 cable coming from the7 day immersion heater.

thanks :)

ok - so the only thing that i can feel by touching the pipes that are not hot (enough) is one of the pipe coming out of the valve towards "central heating" - so must be the valve set to HW only?

ok - well it isnt.

thanks - wish me luck :)

that makes sense as when i switch off the power socket that is powering the boiler (the power socket that has text "fuse" displayed on), the boiler,boiler programmer, pump, valve and cylinder stops BUT the 7 day immersion heater stays on!! so the power to that must be independent as you said.

thanks for all the info - will update tomorrow! kiichi