Central Heating Set-up Does it look right ?

[Biggles..]

TMV on the cylinder is that a requirement for oil...not sure to be honest

New build
Plumbing
Part G

It would still be needed if the cylinder was warmed by gas, electric.

New bathrooms require blended hot water.

 

[gaspro1981]

A little birdie told me that if you have to replace a bath in a dwelling that you now have to provide thermostatic control of the hw temp ??

 

[Biggles..]

Only in bathrooms containing a bath that are new installs ie never had a bath installed before or new build



G3(4) blended water to bath of no more than 48
a) when erected
b) when change of use.

 

[budgie2209]

Hi Thanks for the input.

Like i said i googled, and most of the suggestions you have came up with was what i found out. Another zone valve and the 3 way valve at the thermostaic valve. The by-pass is one i missed. ( and the plumber )

I dont understand the purpose of the 2 way they just fitted, surely the whole point is if the water is still hot then it should shut and recirculate around the manifold and Underfloor? If so i'm sure the pump is the wrong way round also?

Actuators are another matter, they have it set up with constant running? 2 of the loops don't have a thermostat.

Regarding the HW, the bath has its own mixing valve.

thanks

 

[Agile]

What you have shown as a "two way valve" on the inlet to the UFH manifold is a blending valve designed to open when the temperature on the sensor falls below the set 40 C or so.

The idea is that it opens when the UHF returning temperature falls below the set value and the system pump pressure pushes hot water to the UHF manifold.

The UFH circulating pump should be pumping from the bottom towards the top.

The UHF flow manifold should be at about 40 C and the return at ABOUT 30 C but the exact differential will depend on the loop lengths and the heat losses.

Very silly not to time and control the rads and UHF seperately!

Tony

 

[budgie2209]

Thanks Agile,

just had a look at the temp setting's. The blending valve temp is set to 35degree, the temp on the manifold pump is 40 degree.
Should the temp probe not be on the lower manifold?

I'm going to get the plumber's back next week to sort it out, i dont want another winter with it working incorrectly.

thanks

 

[doitall]

However neat and great it looks, the underfloor circuit is wrong.

It needs it's own circuit and controls, so it isn't controlled by the main radiator system.

While I'm looking I cannot see the Pressure reducing valve for the Megaflow, is it fitted else where on the mains.

 

[gaswizzard]

In all honesty it looks very tidy and professional.

Looks like it's been slung in , wrinkled bends , pipework running from A to B , pipework not level , UFH installed incorrectly , this is not even average as far as I'm concerned.

Did the installer have a white stick? , absolute shambles.

 

[doitall]

In all honesty it looks very tidy and professional.

Looks like it's been slung in , wrinkled bends , pipework running from A to B , pipework not level , UFH installed incorrectly , this is not even average as far as I'm concerned.

Did the installer have a white stick? , absolute shambles.

Probably agree, but it's quite good by today's standards.

 

[gaswizzard]

Probably agree, but it's quite good by today's standards.

It's a shame DIA , this trade has gone to the wall , every man and his dog seems to be a 'plumber' these days , be glad to get out of this game as it's getting harder and harder trying to compete with these incompetent fools , the customer is none the wiser so these idiots get away with it.

Yes it peeves me off.

 

[ALEC1]

lets face it we are all working with stuff that is well past its sell by date anyway...

in the modern world the boiler would have its own diverter valve, and the mixing valve would be a mixer module with pump and valve combined in one unit.

It makes nice looking installs easier...and works straight out of the box.

the skill set is changing from pipe laying and construction to understanding the technology and what it is doing and why...

so some up skilling is combined with some de skilling... not good but thats the way it is...

in the abscence of any inspirational regulations or training there is an inevitable compromise...

Two TMVs on one install shows what happens when regulations are taken as engineering guides...

 

[gaswizzard]

lets face it we are all working with stuff that is well past its sell by date anyway

So an excuse for shoddy wormanship?

the skill set is changing from pipe laying and construction to understanding the technology and what it is doing and why...

What technology?

so some up skilling is combined with some de skilling... not good but thats the way it is...

Utter tosh Alec , so a short course in WC (which could be written on the back of a fag packet in comparison) should undermine the training a good 'engineer' should recieve (8 years BTW).

in the abscence of any inspirational regulations or training there is an inevitable compromise...

 

[ALEC1]

well like it or not all boilers have a degree of intelligence that is never fully exploited with out using compensation controls, and the use of these controls forces a different system design..hot water priority for example...

in this install in there would be no pump,manual by pass, the valves. The ufh manifold would be bare with a mixer module...

decent boilers have comprehensive sets of parameters that enable them to be applied to a number of different system designs...

its called progress, the valued skill will be "programming" of the systems...not pipe laying...

I admit its a little futuristic for the UK but thats they way it goes... technology changes working practices...

You only need to look at vaillant, atag or viessmann schematics to see where it is going...

 

[Norcon]

Hi Thanks for the input.

Like i said i googled, and most of the suggestions you have came up with was what i found out. Another zone valve and the 3 way valve at the thermostaic valve. The by-pass is one i missed. ( and the plumber )

I dont understand the purpose of the 2 way they just fitted, surely the whole point is if the water is still hot then it should shut and recirculate around the manifold and Underfloor? If so i'm sure the pump is the wrong way round also?

Actuators are another matter, they have it set up with constant running? 2 of the loops don't have a thermostat.

Regarding the HW, the bath has its own mixing valve.

thanks

OOh dear. Thats a Rehau UFH manifold set up you have there.
Thats their "Compact mixer Unit" which includes a high limit stat.

You need your plumber back asap to rectify it as the pipe laying is incorrect.
I'll see if I can google a schematic for you to arm you with some knowledge. (Its covered in "Technical Manual 864.602EN)


http://www.scribd.com/doc/56599984/8179-Rehau-Ba-Controller-864602-Uk
Page 10 and 11 (Section 2.2)

System flow is to the bottom manifold. The one with the actuaters which is the return from the ufh.
So mixing takes place through the return manifold.
The sensor probe should be inserted in the valve you see on the right of the bottom manifold.
I think it has a capilliary line "packing gland" for wet insertion. Which is the professional way to do it incidentally.

Your current set up is likely dumping boiler high temperature flow into some of the loops.
Not what you want!

A zone valve should be fitted also as already stated and a spring loaded by-pass valve fitted as recommended by Rehau.

The TIV should be set to design flow temperature and the HLS set 15C above design flow temperature as also recommended by Rehau.
A Rehau type BA controller should also be incorporated to operate the 24 volt actuaters and will provide outputs for the secondary pump, main pump and boiler.

So this system has been running for 18 months with no blending facility from the primary circuit and when the guy comes along he fits it totally wrong. Ooh dear oooh dear ooh dear.

I'm off now to do some pipe laying.

 

[oilboffin]

Thank the lord for people like norcon and dan I've been In plumbing for years and it's refreshing that there are still people giving sound advice not the sharp intake of breath these cowboys do when unsuspecting people ask for help I've looked at these photos and think these two gents are dead right
In what they say only thing I would say is I went to a new build and there was no wall stat fitted hope you've got one