Bigger pump ??

[goz666]

Got a job to look at tomorrow, old farmhouse with an extension/granny flat on the side, 19 rads in total. Been there once before and replaced a motorised valve, first plumber fit a 54kw Grant Vortex boiler and told the family that the boiler wouldn't heat the hot water enough so they would need to supplement by using the Immersion.
Anyway I found the gate valve shut down before the two port valve and also the valve not working, replaced both and hot water was spot on and circulation through cylinder was great.
She said they'd also had a problem with two rads not heating up enough in the extension and could they be sorted, had a quick look and found the mains are in 22mm from the main house through to the extension and reduced to 15mm feeds on each rad, except the last two which looks like two 15mm pipes running off the system down into the boarded wall and then tee'd off inside the wall to feed each rad in 15mm.
Best case scenario would be to bring four separate 15mm pipes off the 22mm flow and return and feed each rad separately, but this can't be done as all pipe is boarded over and she doesn't want surface mounted pipe.

I'm thinking of putting a bigger pump on to see if that would help the circulation, the reason it was piped like this apparently was because years ago when they had the extension added it had its own boiler running 5 rads which was removed when she had the big Grant Vortex installed, the plumber then tagged the mains into the main house mains. If that makes sense ?? Bigger pump or not ?? Don't want to promise anything or spend any money until am certain it will work.

 

[SimonG]

Ouch 54kw boiler, sounds a bit ott. Also sounds a bit of a dogs breakfast.

Have you tried balancing the full system first? Cheapest and easiest option. After that then your in the realms of doing stuff that the cust won't be happy with.

 

[Gray0689]

Got a job to look at tomorrow, old farmhouse with an extension/granny flat on the side, 19 rads in total. Been there once before and replaced a motorised valve, first plumber fit a 54kw Grant Vortex boiler and told the family that the boiler wouldn't heat the hot water enough so they would need to supplement by using the Immersion.
Anyway I found the gate valve shut down before the two port valve and also the valve not working, replaced both and hot water was spot on and circulation through cylinder was great.
She said they'd also had a problem with two rads not heating up enough in the extension and could they be sorted, had a quick look and found the mains are in 22mm from the main house through to the extension and reduced to 15mm feeds on each rad, except the last two which looks like two 15mm pipes running off the system down into the boarded wall and then tee'd off inside the wall to feed each rad in 15mm.
Best case scenario would be to bring four separate 15mm pipes off the 22mm flow and return and feed each rad separately, but this can't be done as all pipe is boarded over and she doesn't want surface mounted pipe.

I'm thinking of putting a bigger pump on to see if that would help the circulation, the reason it was piped like this apparently was because years ago when they had the extension added it had its own boiler running 5 rads which was removed when she had the big Grant Vortex installed, the plumber then tagged the mains into the main house mains. If that makes sense ?? Bigger pump or not ?? Don't want to promise anything or spend any money until am certain it will work.

Sounds a bit of a mess to be honest
But what size pump is on system now
Is there any solid fuel / stoves or cooker linked in?

 

[goz666]

First job tomorrow is system balancing, if I can't get a decent flow to the two rads then I'm looking at 'other options' no idea what size pump is on I can't remember tbh.
I told her last time I went I would return before winter and try my best to help her. Apparently there was a solid fuel boiler in the main house system at one time but she assures me it was all removed and capped off a few years ago.
Am not happy with the way the two rads seem to be piped up but fact is there are two pipes off the flow and return that disappear down the wall and somewhere they tee off and go to each rad, can't believe for the cost of two more lengths of pipe and an hours work somebody would do such a half baked job. If balancing doesn't work can only think of two options bigger pump or two pipe boxes and four new pipes direct off the flow and return ?? Pump would be easier ...lol.

 

[Gray0689]

The problem with just putting a bigger pump on is there always the chance it will just simple pump over all time
There is ways round that but without knowing what size pump is on how you know you can
It may already be a 25-80 and then to increase size your going in to commercial pumps maybe flanged ect have you got the room to simple do that
It may end up actually being the cheaper option to re pipe them and re decorate imho
But without seeing job only you can say

 

[Best]

Although mad & i would always come off 22mm, 15mm doing two, (what I assume are big radiators? ) is just about okay if system balanced really well.
Try balancing everything & pay attention to any "open pipe" short circuit points like the old fashioned towel rails that are basically an open pipe flow to return.
Also make sure the cylinder is balanced well, if it is to be heated at same time as rads.
Check if there are any other boilers still linked to system & possibly joined in wrong allowing the rad circuit to short circuit through them.

 

[oz-plumber]

If balancing doesn't work, I would look for a short circuit in the system,
eg; old boiler not capped off, just looped floe & return.

Have you thought about putting in a secondary pump for the area not working?
In the past, we have put secondary pumps in heating systems. Due to circumstances, we have wired them to run constantly because of not being able to run wires back to the boiler.
Although, we only use this as a last option

 

[happyflyer]

Got a job to look at tomorrow, old farmhouse with an extension/granny flat on the side, 19 rads in total. Been there once before and replaced a motorised valve, first plumber fit a 54kw Grant Vortex boiler and told the family that the boiler wouldn't heat the hot water enough so they would need to supplement by using the Immersion.
Anyway I found the gate valve shut down before the two port valve and also the valve not working, replaced both and hot water was spot on and circulation through cylinder was great.
She said they'd also had a problem with two rads not heating up enough in the extension and could they be sorted, had a quick look and found the mains are in 22mm from the main house through to the extension and reduced to 15mm feeds on each rad, except the last two which looks like two 15mm pipes running off the system down into the boarded wall and then tee'd off inside the wall to feed each rad in 15mm.
Best case scenario would be to bring four separate 15mm pipes off the 22mm flow and return and feed each rad separately, but this can't be done as all pipe is boarded over and she doesn't want surface mounted pipe.

I'm thinking of putting a bigger pump on to see if that would help the circulation, the reason it was piped like this apparently was because years ago when they had the extension added it had its own boiler running 5 rads which was removed when she had the big Grant Vortex installed, the plumber then tagged the mains into the main house mains. If that makes sense ?? Bigger pump or not ?? Don't want to promise anything or spend any money until am certain it will work.

Hi,

I got at bit of a kick in another thread about pump size and said that some plumber just fit the same pump and basically never really do a proper pipe
sizing exercise, looks like I didn't need to wait to long for and example to pop up, you really need to do a index circuit calculation before putting on a bigger pump, but if all the pipe is under the floor its a hell of a job, perhaps impossible, bigger pumps cost money, 54Kw is around 1.2 ls and most domestic pump are flat lining at 0.7 ls, what is the pump that is on there now.

Tony

 

[Ermintrude]

Oz wasn't a bad idea, use primary as almost a low loss header, being a pump off that to new bit but put a programmable stat in and run s/l back to boiler do same with rest of house one or two pumps?

 

[solutions]

If you end up fitting an additional pump you could use a pipe stat on the house flow to switch it then you wouldnt have to wire it back to the boiler, programer or wiring center.

 

[Ermintrude]

Was thinking of interlock for different parts of house

 

[solutions]

Was thinking of interlock for different parts of house

Yes makes sense given size of property. I guess you would wire the pump switched as if it were a zone valve.

 

[goz666]

Reyt fellas, thanks.....balancing did the trick all rads now piping hot, just shes asked me now if she can add two more on the system :toilet:

 

[SimonG]

Nice one

 

[oz-plumber]

Hi Fellas,

This thread is whet the forum was designed for.
( I would assume - Croppie might beg to differ ) [ Joking ]

Goz asks a question - has had advice from numerous members.
He has taken on board various suggestions from numerous members and put them into practice.

What has he got out of it?

A happy, contempt customer and some more work from her.

He can, and hopefully within reason, charge his extra work at a premium, and have no doubts that he will have a customer for life.

Well done all,

Oz-Plumber