you need to turn up the temperature on your water heater in the winter, to
make up for the ice cold water you are mixing with it in winter

i.e. the cold water that is part of the shower mixture was cool in the
summer, now it is ice cold and you have to turn up the temp on the water
heater to compensate

cheers!


wrote in message
oups.com...
Hi,
I recently moved into a ten-year old house. The hot water of the shower
worked fine in summer. However, when the outside temperature begins to
drop down around 30, the hot water in the shower does not seem to work.
The faucet water is hot, but the shower water can only reach warm level
at the best. The heating system is in the garage and it is a new system
with only 5 months on it. Two bedrooms have shower, it seems both
showers have the same problem. The shower has one bolt - turning to the
right is cold water and turning the same bolt to the left is the hot
water. Would anyone please give me any hint on what might be wrong with
the hot water in the shower? Thank you very much. - Lily