Whole building with water pressure/hot water problems at peak times

[specialhat]

Hello plumbers!

I hope someone can shed some light on this please.

I live in a Victorian building with four flats. Three out of the four have reported problems with lack of hot water at peak times, 7am to 9am ish. The fourth flat may do but we haven't heard from them in the subject.

We all have separate boilers.

I can't shower at these times because the hot water supply and water pressure is extremely patchy.

Thames Water have been fairly rubbish but eventually they came on Monday to replace three of our four stop valves outside and check the pressure.

Whatever they have done has not fixed the problem (I had no hot water whatsoever this morning), but they are coming back tomorrow to check the pressure. It does seem like the cause is internal though.


Here is what we do know:

1. Ground floor, first floor (me) and second floor are all experiencing low water pressure/no hot water, usually at peak hours between about 7am and 9am. No comment from basement.

2. The problem began in early 2015.

3. Ground floor installed a pump in early 2015, around the same time as the problems began.

4. Ground floor experience the same problems despite having a pump. (I have underlined this as everyone I have spoken to have missed this)

5. Thames Water have been to have a look at the outside stop valves. They have established that second floor and first floor have different stop valves. I do not know about the other flats but it looks likely that we have a stop valve each.

6. Three of the small stop valves were clogged up so TW have cleaned and replaced them. This has not helped the problem.


My plumber suggested:

Looks like there is an internal issue with the pipes. Suggest you run new mains pipe from stopcock in garden to your flat.
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I replied:

What about the other flats? Please note this problem affects the whole building.
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He said:

Might have to do the same with them.
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I replied:

Logically it seems unlikely that the mains pipes for all the individual flats went wrong all at the same time?
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He said:

Quite right. Wait for pressure report.
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Is there any chance that the installation of the ground floor's pump could have caused some damage in some way?

Do you have any other theories please?

 

[MarkAqua]

Do we know if it's a separate pipe to each flat or if they all share the one supply pipe?

If it's shared, my guess would be that the plumber who installed the pump in the basement turned off then mains cold water on a valve somewhere and either didn't fully re-open or broke it nearly closed?

 

[specialhat]

Was the ground floor pump a pump for a shower/bath or was it a main booster pump?

The landlord doesn't know! I'm trying to find out.

Would one of these options have potential to affect the whole building?

 

[specialhat]

Do we know if it's a separate pipe to each flat or if they all share the one supply pipe?

If it's shared, my guess would be that the plumber who installed the pump in the basement turned off then mains cold water on a valve somewhere and either didn't fully re-open or broke it nearly closed?

I believe they are separate. At least there are 4 outdoor stop valves and two of these separately control the second floor and first floor. TW only tested these two in front of me though (I only had access to these flats). But given there are 4 valves and 4 flats I'd assume they had one each.

All the plumbers we speak to keep coming up with suggestions for individual flats but nothing that could link us all together yet.

 

[specialhat]

1. Ask you neighbours either side if they have noticed. If yes(not so likely) then back to TW. If no then problem internal to your properties.
2. Ask basement flat if they have noticed. (Surely the first thing to do)
3. Logic would say that all pipes (whether there is 1,2,3 or 4) must enter the basement then rise through the building. Follow the entire route looking for half closed valves.
4. Has someone by mistake or deliberately shut some valves in the basement not realising what they do or deliberately to give themselves better pressure by giving you less?

I put this to my plumber (who doesn't seem to be thinking logically at all, and he says:

"Not sure why the pipes to the upper flats go through the basement but pipes take strange routes sometimes.

As you wish this to include the whole house it'll be necessary to get tenants / landlords to agree on what to do and to pay for the work. Initial investigation and digging for the pipes will cost £500 approx. let me know if you want that done."

Well, obviously I am in conversation with the other owners about this! And also it seems very drastic to start with digging, doesn't it?!

 

[Tjdservices]

If the pump is boosting the mains then the water board have to approve it before it can be fitted. If it is on the main it would create a bias in supply to the flat with the pump and if your already suffering from low pressure it could exasperate the problem which is why most water authorities won't let you fit a mains boosting pump.

 

[specialhat]

Note the hot water problem affects the people with the pump too.

 

[specialhat]

A development!

I was off work today so spoke to the basement tenants. They had no hot water at all when they moved in last month. A plumber has since fixed this for them (and apparently opened some valves - this has not fixed the hot water problem for the rest of the building). I have asked her to check the hot water at 8am tomorrow so see if it's still a problem for them at peak times.

Furthermore, she says there are four leaks coming from the ground floor flat! She has tried to speak to the tenants about her (they don't speak English) but they refused to let her in. Her managing agent is useless. I have put her in touch with the ground floor owner (his plumber was due this weekend).

Looks like more and more fingers are pointing to the ground floor...

 

[albatross]

I put this to my plumber (who doesn't seem to be thinking logically at all, and he says:

"Not sure why the pipes to the upper flats go through the basement but pipes take strange routes sometimes.
!

If your THICK 'plumber' doesn't think the cold mains for the whole building comes through the basement then where does it go? Up the outside and freeze every winter??

Have you seen the poor water pressure on the ground floor or are you just taking their word for it?
Could they have great pressure due to their pump (and stealing your water) but be lying about it so they don't get blamed and have to remove it?

If the ground floor are refusing to let people in I'd smell a rat!!

 

[specialhat]

No - ground floor pump was installed when old tenants lived there. New tenants moved in last month and they shower at peak times (old ones did not) and complained to their landlord. They didn't know the rest of us had been having problems too when they raised it.

 

[specialhat]

Suspect they didn't let the basement tenant in because the woman there speaks no English and her partner was out.

 

[solutions]

Special hat,
having tead this thread, your posts and other forum members responses, i think it would help you to provide some specifics and detail pertaining to your flat alone (you have access to it so can gather better information).
The other flats are irrelevant to your problem other than they share reportedly similar issues none of which can be confirmed. You mention you have a lack of hot water at peak times. Where in your flat is this evident. Do you have a shower a bath or basin at which you experience the problem or is it all of the above? If all of the above does it affect the kitchen tap too? If so can you measure how many litres per minute of cold water you get from your kitchen sink at peak time? Then measure again how many litres per minute you get of cold at peak time from the kitchen tap but while the bath or shower cold is running simultaneously. Then also do the same for hot water. And perhaps do the same set of tests at off peak times in order to compare. You have a combi boiler. Has the combi boiler's cold Inlet strainer been checked for blockage / restriction?
To avoid any confusion do you have a thermo static mixing shower valve, a manual shower valve, or an electric shower?
Have you asked the ground floor flat what kind of pump has been installed and for what purpose?
If I am to conclude that all the flats have separate mains cold water supply pipe work (separate boundary stopcocks suggests this)
Do they all have combi boilers? If this is the case then the ground floors pump is either incorrectly installed on a mains fed system or is a water boosting pump which could equally be causing the peak time flow issues. Are you sure you know what kind of boiler and hot water system it is that you have? What make and model of boiler is it? Can you gather the same information listed above from your neighbours?

Without a site visit, More specific detailed and definite details are required for forum members to have half a chance of pointing you in the right direction as to the cause of the fault. Even then in cases like this the potential causes are numerous enough that it is essentially just guess work.
Let us know if you get more info or resolve the problem.
Good luck.

Solutions