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- 10
Hello i'm new to the forum, I've done a little searching on here and still have questions.
Some history...
I had 11 double rads in my house then i extended the house and added underfloor heating and 4 more double rads, the extension was all plumbed in and has been running for a year now.
My central heating was/is working but some rads are not as warm as others and the boiler never really shuts off even though none of the 3 stats are calling for heat, sometimes the heat rises rapidly and sometimes it drops rapidly, this doesn't seem to happen as often as it used to before i had the boiler serviced, nothing major was wrong with it just something clogged nothing broken, i think it's struggling with the what to do when the 2 other zones go on and off plus it needs another expansion vessel.
I had the original 11 rads power flushed a month before adding the new ones and the UF.
I had my boiler serviced a few months a go and was advised to add an extra expansion vessel. I used an app to calculate what size and 26.5l is the total size needed so i'm gonna go for a 18l to add on to the 10l inside the boiler.
I'm in the middle of re-decorating the room that the boiler is in and framing a wardrobe around the boiler area so I've got the floor up where all the pipes are to and from the boiler to 2 zone valves and the UF system. One zone valve is for the 4 rads in extension and the other is for the 11 rads in the older part of the house. They are getting moved into the wardrobe.
The UF unit only has 1 loop and a blending valve, the blending valve is impossible to set because when the other zones call for heat the temp increases or decreases, the clip on shut off thermostat inside is set to shut off at 55 degrees but it can't be wired to a zone valve because the 11 rad thermostat controls one zone valve and the 4 rad thermostat controls the other zone valve so i might have a problem there and the underfloor thermostat switches the UF pump on or off at the same time as calling the boiler for heat and CH pump which isn't what it should do from what I've read. The UF pump should always be on.
I have the chance right now to re-plumb everything and re-wire everything so any advice would be really good. I won't be doing the plumbing or re-wiring but in my experience unless i know what should be done it ends up being sub-par or poorly performing because it was done the easy way for example when i first got the UFH fitted i specifically told the plumber i needed a zone valve put in and when the sparky came to wire it up when i was a way i got a phone call to tell me i should have a zone valve fitted!!!
Does the expansion vessel have to go before any zone valves?
Do i need a bypass valve installed to maintain a circulating circuit with all the TRV's and zone valves on the system?
Would the system benefit from flow control valves to balance between the zones, if so where do they go?
The wiring is already a nest so should i get a wiring centre installed?
Would it be a good idea to get an outdoor weather compensator installed because where i live i get four seasons in a day so it sounds like ill save money on my heating. If so where does that get wired to?
I'm going to get a magnetic filter installed close to the return to the boiler after the last rad, is that the best place?
When teeing off to a zone valve and said zone is closed does the dead end in that part of the pipework effect the system in any way?
When a zone's return is teed into another zone's return going back to the boiler should non return valves be fitted or does that not matter? i.e when the return from one zone is coming from the South and the other zone is coming from North and the return to the boiler is going to the West.
My boiler is a Worcester Bosch 42CDi Greenstar and somewhere in the manual it says that 28mm pipe for the gas feed might be required, my pipe is 22mm, is this something that i should get changed? What would be the reason to change it?
Some history...
I had 11 double rads in my house then i extended the house and added underfloor heating and 4 more double rads, the extension was all plumbed in and has been running for a year now.
My central heating was/is working but some rads are not as warm as others and the boiler never really shuts off even though none of the 3 stats are calling for heat, sometimes the heat rises rapidly and sometimes it drops rapidly, this doesn't seem to happen as often as it used to before i had the boiler serviced, nothing major was wrong with it just something clogged nothing broken, i think it's struggling with the what to do when the 2 other zones go on and off plus it needs another expansion vessel.
I had the original 11 rads power flushed a month before adding the new ones and the UF.
I had my boiler serviced a few months a go and was advised to add an extra expansion vessel. I used an app to calculate what size and 26.5l is the total size needed so i'm gonna go for a 18l to add on to the 10l inside the boiler.
I'm in the middle of re-decorating the room that the boiler is in and framing a wardrobe around the boiler area so I've got the floor up where all the pipes are to and from the boiler to 2 zone valves and the UF system. One zone valve is for the 4 rads in extension and the other is for the 11 rads in the older part of the house. They are getting moved into the wardrobe.
The UF unit only has 1 loop and a blending valve, the blending valve is impossible to set because when the other zones call for heat the temp increases or decreases, the clip on shut off thermostat inside is set to shut off at 55 degrees but it can't be wired to a zone valve because the 11 rad thermostat controls one zone valve and the 4 rad thermostat controls the other zone valve so i might have a problem there and the underfloor thermostat switches the UF pump on or off at the same time as calling the boiler for heat and CH pump which isn't what it should do from what I've read. The UF pump should always be on.
I have the chance right now to re-plumb everything and re-wire everything so any advice would be really good. I won't be doing the plumbing or re-wiring but in my experience unless i know what should be done it ends up being sub-par or poorly performing because it was done the easy way for example when i first got the UFH fitted i specifically told the plumber i needed a zone valve put in and when the sparky came to wire it up when i was a way i got a phone call to tell me i should have a zone valve fitted!!!
Does the expansion vessel have to go before any zone valves?
Do i need a bypass valve installed to maintain a circulating circuit with all the TRV's and zone valves on the system?
Would the system benefit from flow control valves to balance between the zones, if so where do they go?
The wiring is already a nest so should i get a wiring centre installed?
Would it be a good idea to get an outdoor weather compensator installed because where i live i get four seasons in a day so it sounds like ill save money on my heating. If so where does that get wired to?
I'm going to get a magnetic filter installed close to the return to the boiler after the last rad, is that the best place?
When teeing off to a zone valve and said zone is closed does the dead end in that part of the pipework effect the system in any way?
When a zone's return is teed into another zone's return going back to the boiler should non return valves be fitted or does that not matter? i.e when the return from one zone is coming from the South and the other zone is coming from North and the return to the boiler is going to the West.
My boiler is a Worcester Bosch 42CDi Greenstar and somewhere in the manual it says that 28mm pipe for the gas feed might be required, my pipe is 22mm, is this something that i should get changed? What would be the reason to change it?
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