Prima 40F Cycling more since new pump

[gazza007]

First post so be patient!!!
I recently had my circ pump replaced on my fully pumped system after my old one failed.
The replacement model is a Wilo Gold R550, very quiet compared to the old one, so it must have been on the way out. Since then my Prima 40F seems to cycle much more than it used to. I thought it may have been to do with an inbalance on the rads as I have also had TRV's fitted & moved my room stat to the hall where there is no TRV.
I have set the boiler stat to max & all the rads eventually get very hot but still cycling more than I think it should. Today I ran-up the system from cold just on the hot water circuit & I was suprised that it still cycled more than I thought it would. So I now know its not the balancing on the rads. It's not rapid on/off cycling but on for say 2 mins then off for a few mins etc etc.

1. Am I being paranoid, is the system behaving normally because it didn't before as the pump was not as effective?

2. The pump speed set to 1, not sure what the old one was set at. Does it need to be higher setting, is the flow too slow allowing the heat to bulid up too much in the boiler.

Any advice or putting my mind to rest appreciated.

Thanks

 

[twgas]

does the boiler shut down when cyl and room stats are satisfied?

 

[gazza007]

Thanks for prompt replyTwgas

does the boiler shut down when cyl and room stats are satisfied?

Yes they both shut down when satisfied.
To be honest I think it's behaving as it should???

It will run constant, till the rads are up to full heat & before the wall stat is satisfied it cycles approx 1 min on, 2 off but can vary a bit from that.

It just takes a good while before the wall stat gets satisfied.

The system is about 12 years old, I had the PCB changed(££££'s) about 16 months ago & changed the Myson actuator earlier this summer. I think when they built these houses the rads they put in the bedrooms are only just enough to do the job.
The reason I moved the wall stat to the small hallway is because I have a open plan lounge/diner with a small kitchen just off the diner, the heat coming from the kitchen cooker & boiler etc would turn off the room stat too early, so upstairs wasn't getting a chance. I then thought it sensible to add TRV's on all the rads but the hall & bathroom as I didn't want the lounge/diner/kitchen being too warm and the extra heat can be used elsewhere making the system more efficient.

 

[twgas]

Is the boiler OK when just HW is selected

what is boiler stat set to?

try turning pump to 2

 

[gazza007]

Cycles just the same when on HW alone when circ temp gets hot.
Boiler stat on Max.