Ideal logic - low dhw pressure

[bassmonster]

Hi all,
I'm not too sure what the exact model of the boiler is but the dhw pressure is really low and not how it used to be. Radiators also taking longer to get hot....

Anything in particular I should be looking for or is just in need of service and power flush?

 

[Masood]

Low DHW pressure won't be cured by a powerflush mate. Slight chance it's limescale on the DHW side of the plate heat exchanger but not that common in my experience. Check the inlet filter for DHW flow issues. Rads not warming up - could be so many things! 🙂

 

[IDCHAPPY]

It's probably on the 5th floor :lol:

 

[bassmonster]

Thanks for that Masood,
Can i please have a "how to check DHW filter for Dummies" Do i need to drain the boiler? i take it i'll need to isolate the flow and return?

if there is limescale on the what's the best way of cleaning it or will the plate heat exchanger need replacing?

 

[GrahamM]

Have look at MI's.
To check clean the dhw filter to got isolate the cw supply. Open lowest hot tap. Remove the flow cartridge, clean filter and reassemble.
If plate hex is gummed up it easier to replace. Cheaper option is to- drain whole system and remove plate. Fill up with spirit of salts. allow it to work. change solution every few hours overnight. completely flush through with clean water and refit.
9 times out of 10 it is as good as new.

 

[bassmonster]

Thanks Graham, you're star :-D

 

[Masood]

Graham is spot on. On Logics the inlet filter is on the right hand water section, behind the condense trap. It's a brass pillar with the Hall effect sensor on it.

Isolate cold inlet and drain as Graham said.
Then remove 2 screws holding the air intake in. Lift and slightly twist that, and remove.
The Hall effect sensor is a black plastic ring with a clear plastic bit on top. It just slides upwards off the brass pillar.
The top of the pillar is a 17mm hex. Undo this, turn upside down and there is the filter.

 

[bassmonster]

Thank you Masood... I'm going to have a crack at this later....

 

[Masood]

Thank you Masood... I'm going to have a crack at this later....

Call me if you get stuck. Oddly enough, just done one today. Cleaned filter and descaled plate hex. Luvvly jubbly. Except I left my bucket, towel and spirit of salts at custard's house...

 

[bassmonster]

Sounds like you went round to have a shower.... Lol

This spirit of salts, what exactly is it?

 

[GrahamM]

Sounds like you went round to have a shower.... Lol

This spirit of salts, what exactly is it?

It is actually an acid so better used outside with protective gloves, mask and eye protection to keep the health and safety guys happy.

 

[bassmonster]

Where can I buy from?

 

[Masood]

Where can I buy from?

Decent plumbers merchants. Pound shops as well, probably.

 

[bassmonster]

it turns it out wasn't the pressure for DHW which was low but the temperature...:32:....turned up the stat and it was sorted..


i just thought I'd check the flow and return temperature while i was there. The flow was 54c and return was 43c. is there an acceptable limit of what the difference should be?

The boiler is set to 78c for heating..