Poor hot water pressure

[Veglen]

Hi all,

I’ve recently changed my kitchen taps from separate hot and cold flow to a Mono mixer type. Due to the high pressure cold water from the mains and the not so high pressure hot water from the tank in the loft I fitted single check valves as per instructions.

However, now the hot water pressure is even less than before! Is this normal and would a water pump fitted in the loft to the hot water supply after the tank be possible and would it make a difference?

Hope you guys can help.

V

 

[holty]

thats the only trouble with new fittings nowadays. their mostly meant for high pressure systems e.g combi.you can go for the option of a whole house pump basically a shower pump, theres many around. as for check valves, it will restrict gravity hot water as its pushing against a seating.

 

[Veglen]

Thanks for the advice Holty,

Any idea on the pressure rating I should be looking for. i.e 1.2, 1.5, 3 Bar etc.

Is there a rule of thumb?

Also are there any reliable makes of house / shower pumps that are reasonably priced and quiet?

Cheers in advance

V

 

[crash3903]

Hi Veglen

At least I can help you with this

As you know, I have fitted a water pump to boost my hot water pressure. It is a watermill BP65S and has increased my pressure brilliantly - It is a 2 bar single impeller pump for my modest 2 bedroom cottage with 2 bathrooms, and kitchen taps

before you buy this pump, check the serial number on the plate at the top - The last 4 digits give you the year and week number of manufacturer. Watermill will not honour the guarantee if it is more that 2 years. For example 0512 is twelth week in 2005 and therefore out of their 2 year warranty period

Hope that helps

C

 

[Veglen]

Thanks crash, thats excellent and just the type of information I was looking for.

One last thing if you don't mind; are these pumps quiet? I am looking at installing the pump in my loft space directly above my bedroom. I get up for work before the misses and as she is a light sleeper. I wouldn't want to wake her

What have you mounted yours on. Is there anything else I need to consider?


V

 

[crash3903]

No probs your welcome

The pump really needs at least a 2m head from your water tank in the loft but will work as low as 600mm. the ideal place would be to install it next to the cylinder in the airing cupboard, the reason being it needs to get the water as close as possible to the cylinder.

The pump I have suggested is very quiet but in the early days it "squeals" a little until the brass impeller beds in.

When you buy the pump, you will also need a surrey flange as well as a 1" male connector for the top of the flange to 22mm (If your pipe is 22mm otherwise to 28mm. Just try it in the plumbers merchant) and a 22mm male connector for the pipe to the pump. The flange is to get water below the air at the top of the tank and disperse any air before it gets into the pump which will cause pulsing, i suggest you invest in this or you will have to do it all again if it doesn't work

Also, don't make the mistake of just tee-ing the vent at the top of the flange into the hot water supply/vent pipe or you will also be into the vent causing a loop of water and your pump won't turn off

This is one that was fitted by a friend - I changed the tee for a proper elbow and capped the pipe off below and it works fine now

Tee into the vent and hot supply

• crash3903
• 30 May 2008
• 1

The wrong way to install a pump :lol:

The vent pipe labelled also went into the vent at the top of the tank causing that affect

Hope that helps

Regards

Crash

 

[Softus]

Also are there any reliable makes of house / shower pumps that are reasonably priced and quiet?

I would fit a brass-bodied pump for pumping the whole house, because you won't have any control over the cooling period needed for a plastic-bodied pump. I would tend to buy a Stuart Turner Monsoon 2.0 bar single impeller unit.

Regarding installation, follow the manufacturer's instructions to the letter. A Surrey flange can be awkward when the side hole ends up pointing in the opposite direction to what you want. I prefer an Essex flange to a Surrey, but some people are put off because it looks scarier, and you need the correct size of hole saws to do it right.

 

[Veglen]

Thanks crash, and Softus,

Just for information, my hot water cylinder is in the loft and there is no other easy access to the hot water pipe that goes down to the kitchen because it is dropped down behind built-in wardrobes in the bedroom.

The water pipe is fed through a 15mm copper pipe in the loft, joins to a lead pipe that runs behind the built-in wardrobes to under the bedroom floor and onto the kitchen. The inside diameter is probably around 15mm too. The lead pipe then changes again to 15mm copper inside a partition wall in the kitchen and onto the mono mixer tap through the check valve. This is why I think the pressure is low. My thought was a pump in the loft would be the easiest option and also out of the way.

The water pressure to the bathroom is better because this is fed by a 22mm copper pipe straight from the hot water cylinder that the kitchen 15mm pipe is teed off from. The bathroom feed goes in a different direction and is 22mm throughout.

However, due to unexpected events over the weekend I have had to put things on hold for the moment. I just wanted to thank you for your input and also to let you know I will view your comments again soon and follow your advice.

Thanks again

V

 

[crash3903]

Also are there any reliable makes of house / shower pumps that are reasonably priced and quiet?

I would fit a brass-bodied pump for pumping the whole house, because you won't have any control over the cooling period needed for a plastic-bodied pump. I would tend to buy a Stuart Turner Monsoon 2.0 bar single impeller unit.

Regarding installation, follow the manufacturer's instructions to the letter. A Surrey flange can be awkward when the side hole ends up pointing in the opposite direction to what you want. I prefer an Essex flange to a Surrey, but some people are put off because it looks scarier, and you need the correct size of hole saws to do it right.

yep agreed - my pump is brass bodied for that reason

I suggested a surrey to Veglen as, like me with electrics, he is not that confident (Sorry if you are Veglen), but i agree an Essex is far better