Back boiler

[ruston]

Looks like you have a gravity hot water system and a pumped heating system so ho do you know well there should be 2 28mm copper pipes running the the immersion. You say there is no 3 way control valve so lets go back to basic. When the system was put in all the radiators just had isolation valves and you had a timeclock with 2 settings 1 hot water 2 hot water and central heating. The thermostat on the boiler was set to 60-65oC and that would have been that. plus if there was a room stat that would have been wired in series from the timeclock to the pump.

So the old way would have been the timeclock hot water putting a switched feed to the boiler so the immersion would heat up to the boiler temperature then if you wanted the central heating on the timeclock 2nd channel would switch on the pump . As for the room stat well that just means to take the timecloclock 2nd channel supply to the pump and reroute it to the room stat then get the room stat to switch the pump on.

Remember the room stat should be fitted in a room ie hall or lounge and the radiator should not have a TRV fitted plus always run a 3 core and earth to the room stat 1. Feed from timeclock 2.switch feed to pump. 3. neutral connection for anticipator resistor on room stat 4. Earth cable

Trouble seems to be Oldtimer they are not maintaining heat to keep it functioning . Seems like they are clueless,not Donny , the customers.

 

[donnysparks]

It's a dodgy system, I've spoke to the client just there to see if she could clear anything up for me! Turns out when the coal fire is on & heating the tank the tank will just over heat unless they turn the switch on to the pump to circulate the water round the rads! Dangerous of you ask me, there's something very wrong with the system I think! She also says all the house are like that and once years ago she came home to hot water ****ing down the chimney breast!
What are your thoughts on that! Think they need a plumber/heating engineer!
Cheers folks and thanks for your comments & help
Donny

 

[ruston]

Yes it will do that if it is just allowed to run on on the hot water side , it will vent into the header tank and overflow through to the outside of the house with a bit of luck and design, eventually the header tank will reach the temp of the boiler, and if it is plastic could collapse with dangerous consequences.

It is normal to have a leak off in the primary , usually in the bathroom to take some of the excess heat away , what was suggested earlier about a pipe stat on the primary return would also help dissipate heat around the rads would also help.

It needs a properly designed system.

 

[donnysparks]

Thanks Ruston, I'm installing a pipe stat tomorrow so hopefully it will help a bit but it does need doing properly! I've asked them to get the fire going so I can find the return pipe, hopefully I get the right one!
Cheers

 

[ruston]

If you can see the boiler the return pipe for the primary will be the bottom one , and as Oldtimer says it will probably be 28 mm . It is not the side with the pump on if it is a gravity system. Same at the tank , the return is the bottom one of the two pipes in the tank centre. prob 28mm .

There is a fill pipe that comes into the bottom of the tank from the header tank , don't confuse it with that one. the top pipe will get hot first , the other is the return.