baxi boilers?

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baxi boilers?

arc

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ok, so the new house has a baxi boiler thingy behind the fire, and it's plotting against us.

upstairs we have a hot water tank, some heating controls and a couple of switches. one switch does the imersion heater in the tank, which is 3kw.. so can stay off for now! the other controls the central heating pump, some 3 way valve thingy and also power to the baxi boiler and fire downstairs.

on the heating controls, the hot water and heating are seperate. we don't want the heating on, just the hot water. so the heating is set to "off" and the hot water to "auto" and has been set to come on for a couple of hours in the morning and a couple of hours in the evening.

soooo.... why does the boiler keep kicking and out all bloody day and using up all our gas. Rough cost atm is around £1 a day in gas, which is stupid when the heating isn't even on.

If i turn the pump etc off, the power to the boiler goes and we loose hot water.

anyone know why it might be coming on and off all day. the stat in the hallway has been set to 15c, so i dont think its trying to not freeze itself. do these things have any other frost protection, maybe the boiler thinks its getting really cold? i don't know.
 

Ffoxy

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As the Water heater is set to "Auto" could it be maintaining the temperature through the day? If there is a manual setting try that with the water heating set to come on twice a day, thats the way ours is and it works.
 
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arc

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the options it has is On, Off, Auto, Allday. With it on Auto, it lets you program it when to come on - and that's what i did. :(
 

jug

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turn your water tank thermostat down, you dont need boiling water for a shower or to wash dishes, that should cut your hot water costs in half.
leave the hot water on constant, it uses less gas to maintain the hot water than it does reheating the whole tank twice daily.

£1 per day is very cheap for gas, far less than average (even a £500 annual cost is below average in uk so £365 is a bargain). how many people are in the house?
 
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arc

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£1 a day when not using the central heating is not right imo, there are 3 of us in the house. the stat on the tank is set to 60.

my point though, WHY is the boiler coming on when its not meant to be. It is meant to be on between 7-8 and 17-19 or something similar.. its not set to maintain temperature in the tank, or set to be on all the time.
 

custard

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hmm im not up on boiler types.
is this the gas type that kicks in when you turn on the hot water or keeps the water hot?
 
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arc

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the one that kicks in when u need water is a combi boiler, which is what im used to.

this one heats the water and stores it in a big pointless tank..
 

jug

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either your timer isnt working or you need to read your boiler's instructions. i'd try reading first.
 
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Usually the hot water only is the boiler on when it heats the water to the command temp and it circulates to the hot water tank by gravity(the hot water rising). There is no connection between the water in the boiler and in the tank, heat is transferred via a copper heating coil. When you put the heat on as well the pump is enabled and will circulate the water through the radiators when the t stat(room not tank) calls for it, so this means the tank stat looses control.
If you have a valve you may well have a pumped hot water system where the difference is that you do not depend on gravity, and the tank stat can still have control even when house heat is on. So on timer the boiler should only run when you comand it on. I have my hot water on timer and a very well insulated tank.
 

Hellcat

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The boiler will only switch on when it has demand for heat. This can be sent from a cylinder stat (hot water tank) or room stat. It can also come from a frost-protect system but that's unlikely in a back boiler.

Is the heating coming on when the boiler is (radiators getting hot)?
 
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arc

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Usually the hot water only is the boiler on when it heats the water to the command temp and it circulates to the hot water tank by gravity(the hot water rising). There is no connection between the water in the boiler and in the tank, heat is transferred via a copper heating coil. When you put the heat on as well the pump is enabled and will circulate the water through the radiators when the t stat(room not tank) calls for it, so this means the tank stat looses control.
If you have a valve you may well have a pumped hot water system where the difference is that you do not depend on gravity, and the tank stat can still have control even when house heat is on. So on timer the boiler should only run when you comand it on. I have my hot water on timer and a very well insulated tank.


i think this is a pumped hot water system. next to the tank there is a 3 way dirvertor valve next to the pump. one pipe comes off that into the tank. one the the pump and one too a pipe that goes downstairs. ive attached a pic.

either your timer isnt working or you need to read your boiler's instructions. i'd try reading first.

rented house and the instructions are not to hand, hence the thread.

The boiler will only switch on when it has demand for heat. This can be sent from a cylinder stat (hot water tank) or room stat. It can also come from a frost-protect system but that's unlikely in a back boiler.

Is the heating coming on when the boiler is (radiators getting hot)?

the heating is set to Off, so it shuold ignore anything from the room stat - and the hot water is only set to be on during certain times, so any other time it should ignore the tank stat. It is certainrtly not cold enough to cause a frost protect system to kick in, unless its faulty - but as you say, unlikely on a back boiler.
 

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jug

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what model is the boiler? i'll get the manual for it.
 

Hellcat

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Right so the heating system is like this diagram..

heating.JPG

Green boiler, Grey radiators, Light blue - hot water cylinder, black - expansion tanks, yellow sinks etc.

No issues with the implementation.

What you (or your landlord) needs to find is what is making this call for heat?

Could you get the model number of the programmer? Do you have a 240V multimeter?
 
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arc

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it's a baxi bermuda inset 2

Right so the heating system is like this diagram..

View attachment 33322

Green boiler, Grey radiators, Light blue - hot water cylinder, black - expansion tanks, yellow sinks etc.

No issues with the implementation.

What you (or your landlord) needs to find is what is making this call for heat?

Could you get the model number of the programmer? Do you have a 240V multimeter?

diagram looks right. the programmer is a servowarm f15 and i have a multimeter that can handle mains AC
 
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jug

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equally difficult to find the manual for, or even a wiring diagram. thats what happens when you fit homeserve stuff :bang:


reading the boiler manual it suggests the controller can be ignored if the boiler thermostat is not adjusted correctly.
 
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arc

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equally difficult to find the manual for, or even a wiring diagram. thats what happens when you fit homeserve stuff :bang:


reading the boiler manual it suggests the controller can be ignored if the boiler thermostat is not adjusted correctly.

boiler stat.. would that be the 'high low' adjustment on the front of it?

Servowarm was an installer of heating systems which disapered when about 1 in 3 of their installed systems went wrong..

What the chance your timer is actually one of these?

http://cgi.ebay.co.uk/Central-heati...4349159QQihZ005QQcategoryZ20598QQcmdZViewItem

it is one of them!
 
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