Expired

Any plumbers on here , need a little help please

33
Found 25th Sep 2013
My boiler temp is reading around 70 to 90 the water out the tap downstairs next to boiler is going warm to hot to warm
upstairs in the bathroom it is going cold to just about warm then cold for about 60 seconds then a little warm then cold again.

temperature on boiler seems to be around 70 to 90 most of the time, temp out of tap upstairs is no where near that.

any ideas?

its a viessmann vitodens 200
Community Updates
33 Comments
You would probably need to add a lot more info about the system you have in place to help anyone diagnose for you...good luck
Mark2111

http://www.homeserve.com/videos/boiler-heating/diagnose-no-hot-water



thank you for that, but that is basic advise, ie is the boiler on, it is on i have hot water downstairs and not upstairs

Edited by: "garbage456" 25th Sep 2013
mosskeeto

You would probably need to add a lot more info about the system you have … You would probably need to add a lot more info about the system you have in place to help anyone diagnose for you...good luck



sure all they have to do is tell me what they need
Not familiar with that model boiler, i presume it's a combi boiler?is your central heating working ok?

If you heating is working ok, quick guess is faulty hot water heat exchanger, do you live in a hard water area?
Edited by: "souljacker" 25th Sep 2013
I'd hazard a guess that the pump is about to fail, hence not enough power to push the hot water upstairs. Is it a combi boiler? Have you been using the heating lately? Do radiators get hot when hot water is on?
souljacker

Not familiar with that model boiler, i presume it's a combi boiler?is … Not familiar with that model boiler, i presume it's a combi boiler?is your central heating working ok?If you heating is working ok, quick guess is faulty hot water heat exchanger, do you live in a hard water area?



+1

Would have said check for a faulty mixer tap valve if only one tap was affected but as the OP describes more than one it's probably the plate heat exchanger as suggested.

An old combi boiler I had, had a diaphragm fail that registered when a hot tap was switched on. It basically worked a valve that switched the boiler from heating mode to hot tap water mode as it could only manage one function at a time. It used to get progressively worse over a period of a couple of months (it failed every 2 to 3 years). Changed the diaphragm and all was good. It relied on water pressure/flow rate so maybe the upstairs tap with a potential lower flow rate would explain differences in temp achieved.
Probably completely wrong though.
Edited by: "Loudmouth" 25th Sep 2013
souljacker

Not familiar with that model boiler, i presume it's a combi boiler?is … Not familiar with that model boiler, i presume it's a combi boiler?is your central heating working ok?If you heating is working ok, quick guess is faulty hot water heat exchanger, do you live in a hard water area?



Yes heating is fine
The Therapist

I'd hazard a guess that the pump is about to fail, hence not enough power … I'd hazard a guess that the pump is about to fail, hence not enough power to push the hot water upstairs. Is it a combi boiler? Have you been using the heating lately? Do radiators get hot when hot water is on?



Oh don't know about radiators will check later
Loudmouth

An old combi boiler I had, had a diaphragm fail that registered when a … An old combi boiler I had, had a diaphragm fail that registered when a hot tap was switched on. It basically worked a valve that switched the boiler from heating mode to hot tap water mode as it could only manage one function at a time. It used to get progressively worse over a period of a couple of months (it failed every 2 to 3 years). Changed the diaphragm and all was good. It relied on water pressure/flow rate so maybe the upstairs tap with a potential lower flow rate would explain differences in temp achieved.Probably completely wrong though.



well we did have similar problem. 2 years ago but that was a flow switch but don't remember last time the upstairs not working when downstairs did.
If your heating is fine it is not the pump as this does both the heating and hot water, try running the boiler in hot water mode only, do the radiators still heat up, if so this points to a faulty diverter valve, if not run a hot tap, does the boiler fire up when you do this? If so, flow switch is ok and as i said it point's to a possible blocked plate heat exchanger (a problem you will get in a hard water area) but not easy to diagnose without actually having a look at boiler
souljacker

If your heating is fine it is not the pump as this does both the heating … If your heating is fine it is not the pump as this does both the heating and hot water, try running the boiler in hot water mode only, do the radiators still heat up, if so this points to a faulty diverter valve, if not run a hot tap, does the boiler fire up when you do this? If so, flow switch is ok and as i said it point's to a possible blocked plate heat exchanger (a problem you will get in a hard water area) but not easy to diagnose without actually having a look at boiler



thanks will try this now

EDIT
the heaters do not heat up, i left the water running for at least 3 minutes, i tried boiler mode only, then standard mode.

boiler is firing up ok it seems

i have no idea if we are in a hard water area sorry.

I turned off taps about 5 minutes ago and can hear the pipes downstairs sounding like they are draining water?


Edited by: "garbage456" 26th Sep 2013
Possible air in the system, is the system pressure ok? There should be a gauge on or near the bolier and the pressure should be between 1 and 1 1/2 bar.
It does seem to point to a faulty/blocked hw plate heat exchanger, not really something you can replace yourself.
souljacker

Possible air in the system, is the system pressure ok? There should be … Possible air in the system, is the system pressure ok? There should be a gauge on or near the bolier and the pressure should be between 1 and 1 1/2 bar. It does seem to point to a faulty/blocked hw plate heat exchanger, not really something you can replace yourself.



It seems to keep moving sometimes 1 and a half at moment it's near 3
most likely as above its a blocked heat exchanger. these scale up often on combi reducing the hot water temp. check the link below and on service instructions page 110.
viessmann.co.uk/con…pdf
And if the pressure is going up to three when the boiler is hot, the expansion vessell is probably faulty or needs re-charging, do you see water running from a pipe outside?
souljacker

And if the pressure is going up to three when the boiler is hot, the … And if the pressure is going up to three when the boiler is hot, the expansion vessell is probably faulty or needs re-charging, do you see water running from a pipe outside?



Yes continously dripping
Sounds like you've got a couple of problems there then, faulty expansion vessel and faulty dhw plate heat exchanger
Thank u all
Just been running downstairs tap and heaters upstairs are hot. This didn't happen when i ran upstairs tap. Grrrrr. This is driving me crazy.
garbage456

Just been running downstairs tap and heaters upstairs are hot. This … Just been running downstairs tap and heaters upstairs are hot. This didn't happen when i ran upstairs tap. Grrrrr. This is driving me crazy.


then u have a fault diverter valve. this wont be the heat exchanger. jump on to the npower boiler plan at £10 a month. they will fix it for u and then just cancel once the 12 months is up. this will work out the cheapest way and u have 12 months peace of mind and no big bills.
kash2013

then u have a fault diverter valve. this wont be the heat exchanger. jump … then u have a fault diverter valve. this wont be the heat exchanger. jump on to the npower boiler plan at £10 a month. they will fix it for u and then just cancel once the 12 months is up. this will work out the cheapest way and u have 12 months peace of mind and no big bills.



Agree, it does sound like the diverted valve if the radiators are getting hot while the hot water is running.

OP, what make/model is the boiler?
The Therapist

Agree, it does sound like the diverted valve if the radiators are getting … Agree, it does sound like the diverted valve if the radiators are getting hot while the hot water is running.OP, what make/model is the boiler?




Viessmann vitodens 200
kash2013

then u have a fault diverter valve. this wont be the heat exchanger. jump … then u have a fault diverter valve. this wont be the heat exchanger. jump on to the npower boiler plan at £10 a month. they will fix it for u and then just cancel once the 12 months is up. this will work out the cheapest way and u have 12 months peace of mind and no big bills.



10 a month sounds very cheap
garbage456

10 a month sounds very cheap


it is but they have added a £50 excess now but british gas do a boiler scheme aswell it will probaly workout the same or cheaper have a look online
kash2013

it is but they have added a £50 excess now but british gas do a boiler … it is but they have added a £50 excess now but british gas do a boiler scheme aswell it will probaly workout the same or cheaper have a look online



signed up for the dearer one at £15 a month, no call out charges and £70 quidco too

standard works out £125.40 + £50 call out = £175.40 - £30 quidco = Total £145.40
Premium care is £186.40 +no call out = £186.40 - £70 quidco = Total 116.40

Edited by: "garbage456" 27th Sep 2013
thank you both
What is the part that has what looks like a car tyre dust valve on top of it. ?
Contacted npower they said they can't fix as it's 14 day cooling off period. Grrrrr

garbage456

What is the part that has what looks like a car tyre dust valve on top of … What is the part that has what looks like a car tyre dust valve on top of it. ?


expansion vessel. yes with npower u do need to wait 14days. but with british gas u can start using it straight away.
kash2013

expansion vessel. yes with npower u do need to wait 14days. but with … expansion vessel. yes with npower u do need to wait 14days. but with british gas u can start using it straight away.



i didnt know i had to wait 14 days if i knew that i would of gone with british gas,

the expansion vessel was dripping a little earlier and it very corroded
Post a comment
Avatar
@
    Text

    Top Discussions

    Top Discussions

    Top Merchants