bit of programmer heol please

working at house at minut and have been asked to replace old analog heating timer with wirless programmable stat.

thing is there is no port valve, just boiler pump and cylinder. the current timer is set to heating and hot water, this runs the pump and boiler so its heating and hot water or nothing, he just turns rads off at valves in summer.

will it be posible to replace the old timmer or will the thermostate cause problems?

any advise

thanks

is there a cylinder stat?

no mate

is there a built in stat on the boiler?

Is it gravity water, pumped heating????

is there a built in stat on the boiler?

Click to expand...

not that i have seen, only stats are trv

Is it gravity water, pumped heating????

Click to expand...

i think so mate

Id be very wary of working on any heating system without stats,

are you sure there are no stats on the boiler?

Well, that's easy then - you need one that will force hw on with ch

But might be better off specifying full control,, as a back covering exercise

its an old floor standing boiler, i will have a better look, it prob will have one somewhere

---------- Post Auto-Merged at 22:58 ---------- Previous post was made at 22:57 ----------

Siemens REV24 RF 7 Day Programmable Wireless Digital Room Thermostat

this is the one he has got

But you will also have to be very careful that what you do couldn't allow the cylinder to boil up

my plumber mate says it prob wolud not be a big job to fit a port valve, also fit a cylinder state, does that sound like best option?

Not a big job and it would allow for a fully pumped system which is much better however the cost might become a sticking point.

If you could push it, I would go for a S plan with 2 x 2 port valves (Honeywell)

thanks mate i think i will push it.

the way it works now i am a bit dubious about altering it so it could be a case of get it done properly or leave it as it is.

is there a chance that the cylinder could boil up as it is, if say he has his heating on for a long period?

Well, if there are no stats as you say then if HW is selected the boiler will just burn and burn and burn,,,

Heating the cylinder up until...????

However gas and oil boilers usually have a thermostat to limit the jacket water temperature so the cylinder shouldn't boil

Boiling cylinders is more of a problem with solid fuel back boilers

the only wiring at the cylinder is for the immersion, there must be one on the boiler.

I will have a good look but still going to push for the port valve

Sounds like old gravity HW, pumped heating.

The BOILER thermostat sets the temperature that the hot water heats up to (and radiators heat to the same temperature).

Usually no room stat, so the house just gets hotter and hotter and it wastes a lot of fuel.

In theory, turning off the pump stops the heating, but in practice there's usually still enough gravity flow to heat the radiators a little, particularly upstairs radiators, hence the need to turn off the valves in the summer.

A very poor and outdated system and it really needs modernising with zone valves.

sorted now, they went for a new 7 day programmer, it was gravity hot water, pumped central heating but with a room stat. boiler did have a stat also.

so they can have HW or heating and HW.

Thanks for advise