Very Hot Rads !

boiler_man

Hi Plumb1, hate to disagree with you as I think we are both on here trying to share some expertise and help others.

but from the previous posts, I think we can assume the system to be gravity DHW with pumped heating, the post complains the rads are getting to hot! (not the rooms are too hot).

The room stat controls the room temperature and will turn off the boiler and pump when achived, the system temp is goverened by the boiler stat. What would have been prudent to ask as you point out in your post is, has the DHW temp become to hot /scolding which would also be indicitive of a failed, incorrectly set or out of calibration boiler stat.

keep up the good work

plumb1_2

Hi Plumb1, hate to disagree with you as I think we are both on here trying to share some expertise and help others.

but from the previous posts, I think we can assume the system to be gravity DHW with pumped heating, the post complains the rads are getting to hot! (not the rooms are too hot).

The room stat controls the room temperature and will turn off the boiler and pump when achived, the system temp is goverened by the boiler stat. What would have been prudent to ask as you point out in your post is, has the DHW temp become to hot /scolding which would also be indicitive of a failed, incorrectly set or out of calibration boiler stat.

keep up the good work

It depends on where the room stat is situated,if its in a hall and getting a cold draft the pump will carry on running,thus not controling the temp of the rads.
What we need to know is the model of the programmer/time clock.
In 99% of older systems the room stat does not shut the boiler down.The room stat will shut off the pump,then when the temperature of the boiler builds up.(hot water not being pumped from boiler) then the boiler stat will close down the gas valve.
As for the the rads getting to hot and not the rooms,if the rooms are hot then the radiators wont disapate the heat as quickly and will keep hot
There are a lot of factors that could cause this problem,and realy it is no good trying to guess a picticular installation,just general points.

Wew have still not heard the outcome of the plumbers visit,or has there been one yet.

budgetflyer

Id turn the boiler stat to mnimum.If the rads still get too hot then its the boiler stat at fault

plumb1_2

Id turn the boiler stat to mnimum.If the rads still get too hot then its the boiler stat at fault

Then its possible the rads wont even get warm then.