I really need your help, 2 zoned system

[Nailey]

Hello everybody. I am worried sick. I recently piped up 6 houses that are a 2 zoned system. 2 normal pressurised systems and 2 combo systems. I have piped a separate rad pipe for rads up and separate for rads down but i have only send one return radiator pipe round for all the radiators.

Today i have tested and fired one of the houses up and the downstairs radiators (running one zone valve) works fine. I have upstairs zone valve turned off via programmer (which controls middle floor and top floor) and the middle floor radiators are getting warm. I obviously should of sent a separate return pipe for each zone. There is no way i can run that in now though as it just wouldn't be possible. So just wondering if there is anything i can do really. I am worried sick.

Many thanks.

 

[rjscan]

zone valves can be on either flow or return, its ok to have a common return to boiler ope all the way, provided the valves are on the flow and are properly installed with branches to eack zone fed of the common flow from the boiler ,check you pipework again and see where your tees are connected, remember ,theres always a way, dont panic,

 

[buckley plumb]

Hello everybody. I am worried sick. I recently piped up 6 houses that are a 2 zoned system. 2 normal pressurised systems and 2 combo systems. I have piped a separate rad pipe for rads up and separate for rads down but i have only send one return radiator pipe round for all the radiators.

Today i have tested and fired one of the houses up and the downstairs radiators (running one zone valve) works fine. I have upstairs zone valve turned off via programmer (which controls middle floor and top floor) and the middle floor radiators are getting warm. I obviously should of sent a separate return pipe for each zone. There is no way i can run that in now though as it just wouldn't be possible. So just wondering if there is anything i can do really. I am worried sick.

Many thanks.

i was told on a course it could be done as you have but i argued saying when the lower circuit is on some of the upper rads could get warm but the lecturer would not have it. always have and always will run a flow and rtn for each floor never had any problems when i have done 4 zone systems . you have prooved what i said on course.i cant see anything you can do as the water will take the easiest route and if thats up the rtn to the upper level rads then it will.you could possibly fit a check valves .
ant

 

[Nailey]

First of all thank you for your replies. I genuinely though one return pipe wouldn't make a difference. How wrong have i been. Where would i fit the check valves though?

 

[diamondgas]

Hi Nailey :welcome:.

Without knowing how you've piped the returns in then its a bit difficult. Are you sure the upstairs zone valve isn't passing?

One thing you could try is a none return valve fitted to the pipe where the reverse flow starts. That could prevent the rest from heating.... As said it depends on how you've piped this up. I'm guessing you've got droppers to downstairs is that right?

 

[Nailey]

Yes that is correct and yes the upstairs zone valve was initially passing. I was made up when i found this out but i have closed the rads up using a gate valve and some of the upstairs rads are still getting warm, also i have piped for combi systems using only one return. Will that also do what this is doing? or will they be ok?

Once again many thanks

 

[buckley plumb]

i agree with diamond gas . and fitting a check valve could work but could also just move the problem to another rad. you may end up putting one on every flow to every upstairs radiator.but dont forget these could break down over time so would need to be accessible.

 

[diamondgas]

Yes that is correct and yes the upstairs zone valve was initially passing. I was made up when i found this out but i have closed the rads up using a gate valve and some of the upstairs rads are still getting warm, also i have piped for combi systems using only one return. Will that also do what this is doing? or will they be ok?

Once again many thanks

As long as the combi isn't zoned then you'll have no problems there mate

 

[buckley plumb]

As long as the combi isn't zoned then you'll have no problems there mate

from what he said in first post looks as if combi is zoned

 

[Nailey]

It is zoned though unfortunately

 

[buckley plumb]

can you run another rtn or is this not possible now. even if you cure the reverse circulation you may get so heat due to natural heat circulation rise from down stairs rads

 

[Nailey]

I can run another return on 2 of the combi's but then 2 houses which are exactly the same would only have one return

 

[diamondgas]

It is zoned though unfortunately

Any chance of doodling a rough drawing of how they're piped taking a picture and posting it up here Nailey. Kind of split up and down and then where you've coupled the respective returns? You may be having to go to the site forman and/or your gaffa with your tail between your legs here though!

 

[buckley plumb]

I can run another return on 2 of the combi's but then 2 houses which are exactly the same would only have one return

if it was me i would change the ones i could and the others try check valves or run a seperate rtn from d/stairs rads and tee in after the other rtn

ant

 

[Nailey]

Where would i put the check valves though. I am tempted as bad as it sounds to leave two of the houses as there is no way i can alter the pipework now and just hope and pray they never have downstairs on and upstairs off. Im so mad at myself.

 

[Nailey]

Diamond gas i can't I'm afraid as the houses are bloody plastered

 

[diamondgas]

Where would i put the check valves though. I am tempted as bad as it sounds to leave two of the houses as there is no way i can alter the pipework now and just hope and pray they never have downstairs on and upstairs off. Im so mad at myself.

From cold set the system away and see which rad return upstairs heats up first. That's the first pipe to stop reverse on! As ant said though you may end up fitting to all!

 

[Nailey]

i have never fit one of those. I don't really know what or where I'm fitting them, sorry

 

[diamondgas]

Diamond gas i can't I'm afraid as the houses are bloody plastered

The issue is with pipework under the floor though yeh? could it be possible to have them lifted and common the upstairs returns in some way as a last resourt?

 

[diamondgas]

i have never fit one of those. I don't really know what or where I'm fitting them, sorry

they have a directional arrow on them that indicates the flow direction. If the return is heating and you're expecting the flow to then you fit the valve arrow in the direction you expect the water to flow i'e' out of the radiator not into it yeh? Down to the floor if your pipes are coming up and out, does that make sense?

 

[buckley plumb]

just thought of another way tee both flows together an have as a single zone but fit honeywell central controled trvs on upstairs rads an option as this gets around building regs but they are not cheap.

ant

 

[Nailey]

kind of. i would need to fit them under the floor near the rads and every rad upstairs right?

it isn't possible to take the floor up really the house it to big. I have to sort this out

 

[Nailey]

i can't really do that buckley as then my boss would know and i would get crucified

 

[buckley plumb]

no link both flows so house is a single zone then fit trvs the digital ones that are rf and work off a room stat to upper floors this is good enought for building regs.did this on a house that a plumber did as a single zone

ant

 

[Nailey]

i know mate but i would have to do it on every house then as the agent is well fussy and the sparks have already done all there wiring and what not. I've tried closing the upstairs valves slightly (not sure if it will do anything) and going to check them again tomorrow. Will the combi one's have the same problem or will they be ok. There is only 6 rads in them