Pump screeching in middle of the night !

[flutterbye]

Hi

When things go wrong with the central hearing, its always in the middle of winter and in this case the middle of the night! I got up to the sound of the pump making a massive racket. Its an S plan system and I noticed that both motorised valves (MVs) were shut but the pump was on. There is no bypass so I guess nowhere for the water to go! I turned on the HW which opened 1 valve and then all was good.

Now I assume this situation arose because the frost stat in the garage (where the boiler is) kicked in ? And I also assume that the ideal solution would be to fit an automatic bypass just after the pump connecting directly to the return? Currently, if both MVs are closed, there is nowhere for the water to go after the pump.

I'd be v grateful for answers to the other questions/confirmations but my main question is this: Given I'd ideally not want to drain down do a lot of pipework right now, could I simply wire the frost stat into one of the MVs (HW?) instead of directly into the pump which is what I think the current arragement is ? If thats not acceptable long term for some reason, would it be ok as a temporary solution for 2 or 3 months when the weather gets warmer?

Thanks again for reading and any useful comments. A great forum.

 

[twgas]

and the boiler is a.............................

 

[doitall]

You can wire the frost stat to open the MV which will also fire the boiler and pump.

Can bypass the programmer or the room stat. Would recommend a pipe stat to turn it off again when the return gets warm.

 

[flutterbye]

Thanks for replies. Boiler is an Ideal 3100.

There is already a frost and pipe stat with the boiler in the garage. The MVs, pump and junction box are long way away in the airing cupboard. When I looked at the wiring today, it looks like there is only one cable leading from the boiler to the airing cupboard and that is connected in to the pump.

So would I be right in thinking I'd need to run another cable from garage to airing cupboard to connect up the frost+pipe stats to an MV? That sounds like more work than draining down and fitting an automatic bypass.