Hot water in exp tank, plus lots of sludge

[The destroyer]

As the title says, I have recently had a new boiler (Ideal HE24) condensing type fitted and I now have very hot water (steaming) getting into the expansion tank in the loft, I checked today and there is also a lot of sludge at the bottom of the tank ??

I have also noticed that the tap water is not getting as hot as it used to with the old boiler.

I am concerned that the plumber who fitted it has not commissioned it properly ??

Also, I checked the hot pipe to the exp tank and it basically just sits at the top of the tank, I have read that it should be approx 18" above ?? Will this cure the hot water problem ??[/i]

 

[chrishutt]

Was the boiler installer Corgi registered? Did he complete the Benchmark record? Did he notify the installation to Corgi?

If the answer to one or more of those questions is no, it could be further evidence that the installer is a cowboy. It sounds as if he has failed to cleanse and flush the system, which is very important for the reliability of the boiler.

 

[brumylad]

Is water overflowing from the expansion tank ?

put a glass under the vent pipe ( the open pipe over the expansion tank) is the water clear or murky

have a look at your pump, whats the maker and the model, was it changed at the same time as the boiler, does it have 3 speed settings

is there a thermostat strapped to the hot water cylinder, what is it set on

is there a motorised valve in the pipe work

is there a room thermostat

 

[noonespecial]

You need to get it sorted mate. If you are getting hot water in the feed cistern either the boiler is overheating or the cold feed / safety open vent pipe connections / pump position are incorrect.

Your heating system is at risk of early failure.

unfortunately for you-it does not sound as if your installer knows what he is doing

 

[The destroyer]

Chrisshut.
As far as I know, the answer is yes to your questions, and he did flush the system, as he decided it was a good idea to vent the dirty water over my driveway. Should I recieve a Cert from corgi once he notifies them ?? I am yet to recieve one, since Nov '05.

Brumylad,
The expsansion tank is not overflowing, when the system is 'off' the level is about 4" at the bottom of the tank, the pump was changed about 6 mths previous to the boiler change and I have to leave it on setting '2' of 3, if I leave it on '1' the downstairs rads do not heat up ! The pump is a cheaper one 'Wilo Gold 50'. Yes there is a thermo on the tank, it is set to 130 (top setting is 180), yes there are motorised valves, although I haven't a clue how they work or what they do ! (I am a telecoms engineer !!). No room thermo, but there is thermo valves on all the rads.

noonespacial,
The pump is situated in a cupboard, upstairs, along with the tank, timer, valves, etc.

Any, suggections are welcome, I have contacted the guy who fitted it, but he is just not turning up !!!

 

[noonespecial]

Chrisshut.
The pump is situated in a cupboard, upstairs, along with the tank, timer, valves, etc.

The actual physical location is not really important. What is though is the relative connection points in the heating system of the pump, cold feed connection and safety open vent connection to the system. These are likely to be incorrect from what you are describing. If that is so hot heating water is being pumped up the safety open vent pipe into the feed and expansion cistern

 

[jobloggs]

If you have no room stat then the boiler and pump are being controlled by the timer and boiler stat.

The tank stat will shut of the flow to the HW cylinder coil when satisfied. The TRVs will close off the radiators when warm.

Question now is where will the circulating pump circulate water to?
Answer: Up the vent and back down the feed if they are connected on the flow side of the pump.

They should be teed in close together on the low pressure side of the pump. However even in that case the pump will be pumping into closed off Ch & HW loops when stat and TRVs are satisfied. This is hard work for the pump unless you have either an open rad without a TRV or an auto bypass valve connecting the pressure side of pump to the return to the boiler. Pump will run continuously and boiler will cycle on its own thermostat. (Unless that goes wonky and boiler boils)

You really need to upgrade your controls (room stat in room without radiator TRVs and another zone valve all correctly wired up ) so that boiler and pump are both switched off when both stats are satisfied. A lot more components have now got to go wonky at the same time before boiler boils.

Look up Honeywell or Pegler web sites for s plan arrangements.

 

[The destroyer]

jo bloggs,

thanks, very informative. Why would this have only started with the fitting of a new boiler ??
What are the consequences of the boiler 'boiling' ? and how much roughly would I be looking at to rectify the situation ?
I paid the plumber £1400 for fitting the boiler, should I get him back to finish the job properly ?

 

[jobloggs]

Boiler boiling. Lot of steam going up vent into roofspace plus a bit of noise. New boiler will likely have a high level stat as well as the stat to control temp so risk is small but thats why vent is there.

You mention in one of your posts that you have motorised valves(plural). What does any not on the HW circuit do? Usually the second one is controlled by the room stat.

How easy it would be to rectify problems depends on where the pump valves, HW cyl, vent and feed pipes are relative to each other. If you can post a schematic drg you might get further advice.

My understanding is that when boiler is replaced now regs require updating of controls to one of the plans (s, y, w etc). The plumber should have at least told you what was required in this respect.

 

[jobloggs]

have a look ath this:

http://www.pegler.co.uk/training/index2.html

 

[JohnD]

No room thermo,

That's odd, I wonder why not. It will tend to run when not required, and use fuel unnecessarily.

 

[The destroyer]

Jobloggs
The plumber, said not to bother with a room therm as I had TRV's on all the rads and to be honest I was a bit naive as to the building regs side of things, as was he by the sound of it !!

Thanks for that link, good info, once I get my head round what I actually have, I will post a diagram. I got in the loft earlier and when I turn the pump down to number 1, it stops venting to the exp tank, (might sound obvious, but I only found out tonight).

Cheers

 

[chrishutt]

Should I recieve a Cert from corgi once he notifies them ?? I am yet to recieve one, since Nov '05.

Yes, if he notified Corgi as required, you would have received a letter from them shortly afterwards confirming that a Corgi registered installer had complied with Building Regs (which he clearly hasn't if he didn't fit a room stat).